RNO Analysis Mate V1

RNO Analysis Mate RNO Mate 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

NO Analysis Mate Developed By: Manik Kapoor Contact: [email protected]

RNO Mate 3G Congestion HW Channel Element 3G Events CQI Cpich Power F1 F2 Layering Policy GSM DCS Traffic Sharing Handover 2G 2G Cell Reselection Frequency Hopping Parameters 2G Congestion 2G Handover Problem 2G Call Drop 2G Power Control 2G DCR HW Parameter Counter Relationship HW 3G Congestion NSN Congestion Huawei 2G Congestion Nokia 2G Congestion Siemens 2G Events Preventive 3G Huawei RTWP 3G Huawei-HSDPA & HSUPA

Click to return to main page Case CE Blocking/CE High Util

1st Action Verify CE license and CE board capability. Commands involved : DSP LICENSE, DSP BBPTC

Iub Blocking/Iub High Util

Verify Iub BW setting in Node-B and in RNC. Sets involved : IPPATH, IPLOGICPORT

DL- Power Blocking/DL - Power High Util

Physical Audit

UL- Power Blocking

Physical Audit

Code Blocking

Physical Audit

2nd Action

3rd Action

Physical Audit

CE license and/or board upgrade

Physical Audit

Iub BW upgrade

Modify DL CAC parameters set to higher value. Parameters involved : Activate 40W, maintain existing PCPICH DLCONVAMRTHD, setting DLCONVNONAMRTHD, DLOTHERTHD, DLHOTHD, DLCELLTOTALTHD Increase ULTOTALEQUSERNUM (e.g from Turn-off NBMULCACALGOSELSWITCH 160 to 180) (set to ALGORITHM_OFF) Modify DLHOCECODERESVSF to lower SF (e.g from SF32 to SF 64)

Reduce HSPDSCHMINCODENUM (e.g from 5 to 4)

4th Action Modify LDR threshold. Sets involved : UCELLLDM, UCELLLDR Modify FTI to reduce Active Factor. Sets involved : TRMFACTOR, ADJMAP, ADJNODE

Reduce HSSCCHCODENUM (e.g from 4 to 3)

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Channel Element (CE) Resource CE resources are a type of NodeB hardware resource. The number of CEs supported by single NodeB indic The more CEs a NodeB supports, the more powerful the channel demodulation and service processing capa different numbers of CEs to ensure proper channel demodulation.

In a RAN, CE resources are managed by both the RNC and NodeB. The NodeB reports its CE capacity to the R the number of CEs that need to be consumed and controls CE resources during CE congestion. This ensure CE resources and rapidly adjusts the number of CEs that can be consumed based on the actual service rate.

A proper use of CE resources increases the number of UEs that can be admitted and improves the service qu

Basic Channel Element Concepts CE is a basic unit that measures the channel demodulation capabilities of a NodeB. CEs are classified into up One UL CE needs to be consumed by a UL 12.2 kbit/s voice service (SF = 64) plus 3.4 kbit/s signaling. One DL CE needs to be consumed by a DL 12.2 kbit/s voice service (SF = 128) plus 3.4 kbit/s signaling.

If only 3.4 kbit/s signaling traffic is carried on a DCH or HSPA channel, one CE still needs to be consumed. types can be calculated by analogy. The number of UL and DL CEs supported by a NodeB is determined by the NodeB hardware capabilities and by the NodeB hardware is called the physical CE capacity. The licensed CE capacity may differ from the ph can be used by an operator. CE is a concept of the NodeB side. On the RNC side, it is called NodeB credit. The RNC performs admission number of Node credit resources is twice that of CEs. In the DL, the number of NodeB credit resources equals CE Sharing in a Resource Group

To facilitate baseband resource management, NodeB baseband resources fall into UL and DL resource groups

UL Resource Group

UL resource group is a UL resource pool shared on a per-channel basis, more than one cell can be setup in baseband boards, but one board can belong to only one UL resource group. CE resources in one UL resource cell in a UL resource group can set up services on any board in the group. The physical CE capacity of a UL group. DL Resource Group Different from a UL resource group, a DL resource group is shared on a per-cell basis. Resources in a DL re one board can be configured to multiple DL resource groups. DL CE resources for UEs in the same cell can resources in one DL resource group can be shared only within a baseband board.

NodeB CE Capacity Specifications Typically different baseband boards of a NodeB have their own CE capacity specifications. For exampled, baseband board, see the BBU3900 Hardware Description product by Huawei CE capacity here refers to the number of CEs that can be consumed by UL and DL R99 services and HSUPA s common and HSDPA channels.

Rules for Calculating CE Consumption The RNC determines the number of CEs required for a service based on the SF that matches the service ra resources must be allocated or taken back and the number of CEs must be deducted or added accordingl channels or services of different types. CE resources reserved by the NodeB for common and HSDPA channels are shown in gray. CE resources that need to be consumed by R99 and HSUPA services are shown in pink.

Common Channels CE Consumption CE resources required on the UL and DL common channels are reserved by the NodeB. Therefore, they do considered in the calculation of CE consumption.

HSDPA Channels CE Consumption Similarly, the NodeB reserves CE resources for the high-speed downlink shared channel (HS-DSCH) and the need to be considered in the calculation of CE consumption. Note that the signaling of an HSDPA UE that is not performing an R99 service occupies one DCH and needs the signaling of an HSDPA service does not consume additional CE resources. For an HSDPA UE that is perfo same DCH. Therefore, only the CEs consumed on R99 traffic channels need to be calculated.

R99 Service CE Consumption For an R99 service, the RNC determines the number of CEs and NodeB credit resources that need to be cons the service.

Direction UL

DL

HSUPA Service CE Consumption For an HSUPA service, the RNC determines the number of CEs and NodeB credit resources that need to be determines the SF based on a certain rate in the following ways: If the UL enhanced L2 function is disabled and the NodeB indicates in a private information element (IE) th the RNC calculates the SF based on the larger of the bit rate of one RLC PDU and the guaranteed bit rate (GB

If the UL enhanced L2 function is disabled, the RLC PDU size is fixed. The bit rate of one RLC PDU is determin If the UL enhanced L2 function is enabled and the NodeB indicates in a private IE that dynamic CE resource SF based on the larger of the bit rate of the smallest RLC PDU and the GBR. If the UL enhanced L2 function is enabled, the RLC PDU size is flexible. The bit rate of the smallest RLC P minimum RLC PDU size can be specified by the RlcPduMaxSizeForUlL2Enhance parameter. If the NodeB reports that dynamic CE resource management has been disabled, the RNC calculates the SF ba If the NodeB does not report whether dynamic CE resource management has been enabled, the RNC calcu parameter and whether the UL enhanced L2 function is enabled. If HsupaCeConsumeSelection is set to MBR, the RNC calculates the SF based on the MBR. If HsupaCeConsumeSelection is set to GBR: If the UL enhanced L2 function is disabled, the RNC calculates the SF based on the larger of the bit rate of on If the UL enhanced L2 function is enabled, the RNC calculates the SF based on the larger of the bit rate of the After determining the SF, the RNC searches the CE consumption mapping listed below Direction UL

CE Consumption of 4-Way Receive Diversity The use of 4-way receive diversity does not affect DL CE consumption but doubles UL CE consumption. The UL CE consumption of a resource group doubles if the resource group is configured with 4-way receive unchanged. examples of CE Consumption UE A, which performs a UL 64 kbit/s and DL 384 kbit/s service on the DCH, consumes three UL CEs and eight UE B, which performs a UL 64 kbit/s and DL 1024 kbit/s service on the DCH and HS-DSCH respectively, con (SRB) is carried on the DCH. UE C, which performs a UL 608 kbit/s and DL 1024 kbit/s service on the E-DCH and HS-DSCH respectively nine UL CEs and one DL CE.

Rate (kbit/s)

SF

Number of CEs Consumed

Corresponding Credits Consumed

3.4 13.6 8 16 32 64 128 144 256 384 3.4 13.6 8 16 32 64 128 144 256 384

256 64 64 64 32 16 8 8 4 4 256 128 128 128 64 32 16 16 8 8

1 1 1 1 1.5 3 5 5 10 10 1 1 1 1 1 2 4 4 8 8

2 2 2 2 3 6 10 10 20 20 1 1 1 1 1 2 4 4 8 8

Rate (kbit/s) 8 16 32 64 128 144 256 384 608 1450

SF 64 64 32 32 16 16 8 4 4 2SF4

Number of CEs Consumed 1 1 1 1 2 2 4 8 8 16

Corresponding Credits Consumed 2 2 2 2 4 4 8 16 16 32

2048 2890 5760

2SF2 2SF2 2SF2+2 SF4

32 32 48

64 64 96

Click to return to main page Event Name event 1A event 1B event 1C event 1D event 1E event 1F event 1G event 1H event 1I Event Event Event Event Event Event

2a 2b 2c 2d 2e 2f

Event Event Event Event

3a 3b 3c 3d

event 4 A event 4 B event 5A event event event event event event event

6A 6B 6C 6D 6E 6F 6G

Event 7a Event 7b Event 7c

A Primary CPICH enters the reporting range; addition of a radio link. A primary CPICH leaves the reporting range; removal of a radio link. A non-active primary CPICH becomes better than an active primary CPICH; replacement of the wor Change of best cell A Primary CPICH becomes better than an absolute threshold A Primary CPICH becomes worse than an absolute threshold Change of best cell (TDD) Timeslot ISCP below a certain threshold (TDD) Timeslot ISCP above a certain threshold (TDD)

Change of best frequency The estimated quality of the currently used frequency is below a certain threshold and the estimat The estimated quality of a non-used frequency is above a certain threshold The estimated quality of the currently used frequency is below a certain threshold; start compress The estimated quality of a non-used frequency is below a certain threshold The estimated quality of the currently used frequency is above a certain threshold; stop compress The estimated quality of the currently used UTRAN frequency is below a certain threshold and the The estimated quality of other system is below a certain threshold The estimated quality of other system is above a certain threshold Change of best cell in other system Transport Channel Traffic Volume becomes larger than an absolute threshold Transport Channel Traffic Volume becomes smaller than an absolute threshold A predefined number of bad CRCs is exceeded The The The The The The The

UE UE UE UE UE UE UE

Tx power becomes larger than an absolute threshold; start compressed mode Tx power becomes less than an absolute threshold; stop compressed mode Tx power reaches its minimum value Tx power reaches its maximum value RSSI reaches the UE's dynamic receiver range Rx-Tx time difference for a RL included in the active set becomes larger than an absolute t Rx-Tx time difference for a RL included in the active set becomes less than an absolute thr

The UE position changes more than an absolute threshold SFN-SFN measurement changes more than an absolute threshold GPS time and SFN time have drifted apart more than an absolute threshold


CQI stands for Channel Quality Indicator. As the name implies, it is an indicator carrying the inf quality is. This CQI is for HSDPA.

CQI is the information that UE sends to the network and practically it implies the following two i) Current Communication Channel Quality is this-and-that.. ii) I (UE) wants to get the data with this-and-that transport block size, which in turn can be directly converted

In HSDPA, the CQI value ranges from 0 ~ 30. 30 indicates the best channel quality and 0,1 indicates the poor network transmit data with different transport block size. If network gets high CQI value from UE, it transmit

What if network sends a large transport block even though UE reports low CQI, it is highly probable that UE fa NACK to network and the network have to retransmit it which in turn cause waste of radio resources.

What if UE report high CQI even when the real channel quality is poor ? In this case, network would send a la would become highly probable that UE failed to decode it (cause CRC error on UE side) and UE send NACK to cause waste of radio resources.

How UE can measure CQI ? This is the most unclear topic to me. As far as I know, there is no exp which the CQI is calculated, but it is pretty obvious that the following factors play important role signal-to-noise ratio (SNR) signal-to-interference plus noise ratio (SINR) signal-to-noise plus distortion ratio (SNDR)

It is not defined in the specification on how these factors are used and whether there is any other factors bei Usually at chipset development stage, they do a lot of testing to correlate the measured SNR and the measu equation) for the correlation. And the mapping table (function) would eventually used to determine CQI value

In LTE, there are 15 different CQI values randing from 1 to 15 and mapping between CQI and mod follows (36.213)

If you are an engineer in Network (eNodeB) programming, you need to know the number of resource blocks a CQI 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Note 1 : Refer to Throughtput Calculation Example for determining N_RB, MCS, TBS determination.

Note 2 : REs/PRB varies depending on CFI value as follows. CFI 1 2 3 Note 3 : I used the following formula explained in Code Rate section. v_CodingRate := (int2float(p_TBSize + 24)) / (int2float(p_N_PRB * tsc_REs_Per_PRB * v_BitsPerSymbol));

CQI is carried by PUCCH or PUSCH depending on the situation as follows. Carried by PUCCH : Periodic CQI Carried by PUSCH : Aperiodic CQI.

Regarding CQI report period and configuration, refer to CQI, PMI, RI Reporting Configuration part.

< Two Important CQI Table >

We have two different tables as shown below defined in 36.213. Now the question is in which situation the fir second table(Table 7.2-1) is used). Overall story is described in 36.213 section 7.2, I will just re-organize thos

The table shown above is used in following situation. In this table, 4 bit is used to indicate each CQI value.

1) For transmission modes 1, 2, 3 and 5, as well as transmission modes 8, 9 and 10 without PMI/RI report 8, 9 and 10 with PMI/RI reporting and RI=1 2) For RI > 1 with transmission mode 4, as well as transmission modes 8, 9 and 10 with PMI/RI reporting, bit CQI (16 different value) is reported for each Codeword (CW0 and CW1).

Following is another table that is used for CQI report, but this is not the absolute value. It is a different value defined ? It is defined as follows : Codeword 1 offset level = wideband CQI index for codeword 0 – wideband CQI index for codeword 1.

This table is used in following case :

1) For RI > 1 with transmission mode 4, as well as transmission modes 8, 9 and 10 with PMI/RI reporting, CQI for codeword 0 according to Table 7.2.3-1 and a wideband spatial differential CQI

Modulation QPSK QPSK QPSK QPSK QPSK QPSK 16QAM 16QAM 16QAM 64QAM 64QAM 64QAM 64QAM 64QAM 64QAM

Bits/Symbol 2 2 2 2 2 2 4 4 4 6 6 6 6 6 6

REs/PRB 138 138 138 138 138 138 138 138 138 138 138 138 138 138 138

N_RB 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20

MCS 0 0 2 5 7 9 12 14 16 20 23 25 27 28 28

TBS 536 536 872 1736 2417 3112 4008 5160 6200 7992 9912 11448 12576 14688 14688

REs/PRB 150 138 126

Code Rate 0.101449 0.101449 0.162319 0.318841 0.44221 0.568116 0.365217 0.469565 0.563768 0.484058 0.6 0.692754 0.76087 0.888406 0.888406


CPICH power typically takes about 8~10% of the total NodeB power. For a 20W (43dBm) NodeB, In urban areas where in-building coverage is taken care of by in-building installations, the CPICH m 1) The coverage area is small since users are close to the site, and 2) More power can be allocated to traffic channels



For traffic balancing using HODCS - DCS / GSM - GSM : means same layer, you can using PBGT HO parameterDCS - GSM your reference)or you may set CRO for DCS bigger than GSM to attract more traffic to DCS and reduce ping-pong HO,or y attachment. _____________ The same layer of Cell, you can optimize with PBGT HO Threshold, CRO or load handover supp

Inter-Layer HO Threshold:30 Inter-Layer HO Hysteresis:31 EDGE DL HO Threshold:25 When G18 stand for Serving Cell-RxLev of GSM1800 lower than-83dBm will HO to GSM900 trigger by EDGE HO=-85dBm2 HO . Depending on your settings, retuning some parameters among the below listed mayhelp you achieve the desired Tr

Inter-layer HO ThresholdREXLEV_ACCESS_MINTch Traffic busy Threshold(%)AMR TCH/H Prior Cell Load ThresholdEdge HO RX_LEV Upper ThresholdAMR UL RX_LEV Lower ThresholdDL RX_LEV Upper ThresholdDL RX_LEV Lower ThresholdUL RX_L CRO Load HO Allowed Load HO Threshold REXLEV_ACCESS_MIN Tch Traffic busy Threshold(%) AMR TCH/H Prior Cell Load Threshold Edge HO UL RX_LEV Threshold Edge HO DL RX_LEV Threshold AMR DL RX_LEV Upper Threshold AMR DL RX_LEV Lower Threshold AMR UL RX_LEV Upper Threshold AMR UL RX_LEV Lower Threshold DL RX_LEV Upper Threshold DL RX_LEV Lower Threshold UL RX_LEV Upper Threshold UL RX_LEV Lower Threshold UL Expected Level at HO Access


Handover and Related Parameters 4.8.1 PBGT Handover Threshold (HoMargin) I. Definition

The PBGT handover threshold is power handover tolerance (handover in serving areas). handover occurs. Complex radio propagation conditions cause fluctuation of signal level handover threshold is similar to HO_MARGIN (GSM 05.08). II. Format

The PBGT handover threshold ranges from 0 to 127, corresponding to –64 dB to +63 dB. T 72. III. Configuration and Influence

The PBGT handover threshold aims to adjust handover difficulty properly, and to avoid p less efficient. When it is smaller than 64, the MS hands over from the serving cell to the

4.8.2 Minimum Downlink Power of Handover Candidate Cells (rxLevMinCell) I. Definition

It is the minimum allowed access level for a cell to be a neighbor cell. When the cell lev list for handover judgment. II. Format It ranges from –110 dBm to –47 dBm. III. Configuration and Influence It is helpful in the following two aspects: l It

guarantees communication quality.

For a common single layer network structure, the value ranges from –90 dBm l It

helps allocate traffic between cells averagely.

Especially in multi-layer network structure, to maintain MS in a network lay decrease that in other cells. IV. Precautions

You cannot configure rxLevMinCell over great (over –65 dBm) or over small (lower than –

4.8.3 Handover Threshold at Uplink Edge I. Definition

If the uplink received level keeps being smaller than the handover threshold at uplink ed II. Format

It ranges from 0 to 63, corresponding to –110 dBm to –47 dBm. The recommended values l Configure

it to 25 in urban areas without PBGT handover.

l Configure

it to 20 in single site of suburban areas.

l Configure

it to 20 in urban areas with PBGT handover

III. Configuration and Influence

When PBGT handover is enabled, the corresponding edge handover threshold can be low artificial cross-cell non-handover occurs. Therefore call drop occurs or intra-frequency a

4.8.4 Handover Threshold at Downlink Edge I. Definition

If the downlink received level keeps being smaller than the handover threshold at down II. Format

It ranges from 0 to 63, corresponding to –110 dBm to –47 dBm. The recommended values l Configure

it to 30 in urban areas without PBGT handover.

l Configure

it to 25 in single site of suburban areas.

l Configure

it to 25 in urban areas with PBGT handover


When PBGT handover is enabled, the corresponding edge handover threshold can be low artificial cross-cell non-handover occurs. Therefore call drop occurs or intra-frequency a

4.8.5 Downlink Quality Restriction of Emergency Handover I. Definition

If the downlink received quality is lower than the threshold of downlink quality restricti II. Format It ranges from 0 to 70, corresponding to RQ (QoS 0 to 7) x 10. The recommended value is 50. III. Configuration and Influence

When frequency hopping is enabled, the voice quality is better with the same RQ, you c occurs first. If there are no other candidate cells, and the intracell handover is enabled,

4.8.6 Uplink Quality Restriction of Emergency Handover I. Definition If the uplink received quality is lower than it, quality difference emergency handover is II. Format It ranges from 0 to 70, corresponding to RQ (QoS 0 to 7) x 10. The recommended value is 50. III. Configuration and Influence

When frequency hopping is enabled, the voice quality is better with the same RQ, you c occurs first. If there are no other candidate cells, and the intracell handover is enabled,

4.8.7 Uplink Quality Threshold of Interference Handover I. Definition

It is the uplink received quality threshold of the serving cell that triggers interference h l The

uplink received level is higher than the uplink received power thr

l The

uplink received quality is lower than the uplink quality threshold

When handover switch is enabled, the interference handover occurs within the cell by p II. Format It ranges from 0 to 70, corresponding to RQ (QoS 0 to 7) x 10. The recommended value is 50. III. Configuration and Influence

When frequency hopping is enabled, the voice quality is better with the same RQ, you c according to the sorted result. If the serving cell ranks first and its intracell handover is

4.8.8 Downlink Quality Threshold of Interference Handover I. Definition

It is the downlink received quality threshold of the serving cell that triggers interference l The

downlink received level is higher than the downlink received pow

l The

downlink received quality is lower than the downlink quality thres

When handover switch is enabled, the interference handover occurs within the cell by p II. Format It ranges from 0 to 70, corresponding to RQ (QoS 0 to 7) x 10. The recommended value is 50. III. Configuration and Influence

When frequency hopping is enabled, the voice quality is better with the same RQ, you c according to the sorted result. If the serving cell ranks first and its intracell handover is IV. Precautions The interference handover quality must be better than emergency handover quality.

4.8.9 Uplink Received Power Threshold of Interference Handover I. Definition

If interference handover occurs due to uplink quality, the serving cell must reach the mi interfered, so interference handover is triggered. The interference handover is triggered if all the following conditions are met: l The

uplink received level is higher than the uplink received power thr

l The

uplink received quality is lower than the uplink quality threshold

When handover switch is enabled, the interference handover occurs within the cell by p II. Format It ranges from 0 to 63, corresponding to –110 dBm to –47 dBm. The recommended value is 25. III. Configurationa and Influence When interference handover is triggered, select the candidates according to the sorted the serving cell; otherwise it selects the second candidate cell.

4.8.10 Downlink Received Power Threshold of Interference Handover I. Definition

If interference handover occurs due to uplink quality, the serving cell must reach the mi is interfered, so interference handover is triggered. The interference handover is triggered if all the following conditions are met: l The

downlink received level is higher than the downlink received pow

l The

downlink received quality is lower than the downlink quality thres

When handover switch is enabled, the interference handover occurs within the cell by p II. Format It ranges from 0 to 63, corresponding to –110 dBm to –47 dBm. The recommended value is 30. III. Configurationa and Influence When interference handover is triggered, select the candidates according to the sorted the serving cell; otherwise it selects the second candidate cell.

4.8.11 Maximum Repeated Times of Physical Messages (NY1) I. Definition

In asynchronous handover process of GSM system, when the MS receives handover messa network receives the message, it does as follows:

1) Calculate related RF features. 2) Send physical messages (it the channel messages are encrypted, start 3) Start timer T3105.

If the network does not receive correct layer 2 frames sent by MS until expiration of T31 for resending physical messages is determined by the parameter maximum repeated tim II. Format NY1 ranges from 0 to 254. The recommended value is 20. III. Configuration and Influence

When the network receives the handover access messages sent by MS, the physical chan guaranteed, the MS can receive physical messages correctly and send layer 2 frames to t

If the physical messages are sent multiple times, and the network cannot receive layer 2 after multiple trials, the communication quality is not guaranteed. This lowers the utiliz IV. Precautions

Configuring NY1 is affected by T3105. If T3105 is configured to a short value, then the N

If a handover trial fails before the original cell receives the HANDOVER FAILURE message FAILURE INDICATION message to the target BSC. Though the MS might return to the origin connection failure. To avoid the previous phenomenon, configure T3105 as follows:

Ny * T3105 > T3124 + delta (delta: the time between expiration of T3124 and receiving H

4.8.12 Multiband Indicator (multiband_reporting) I. Definition In a single band GSM network, when the MS send measurement reports of neighbor cells signals.

In a multiband network, operators wish that MS uses a band by preference in cross-cell h signal band. The parameter multiband indicator indicates MS to report content of multib II. Format The multiband indicator ranges from 0 to 3, with meanings as follows: l 0:

According to signal strength of neighbor cells, the MS must report si with the neighbor cells in whatever band. l 1:

The MS must report the allowed measurement report of a neighbor the serving cell. The MS must also report the neighbor cells of the band used conditions of other neighbor cells in any band. l 2:

The MS must report the allowed measurement report of two neighb by the serving cell. The MS must also report the neighbor cells of the band u report conditions of other neighbor cells in any band.

MS must report the allowed measurement report of three neigh by the serving cell. The MS must also report the neighbor cells of the band u report conditions of other neighbor cells in any band. l 3: The


In multiband networks, it is related to traffic of each band. For configuration, refer to t l If

the traffic of each band is approximately equal, and operators do no

l If

the traffic of each band is obviously different, and operators want M

l For

situations between the previous two, configure multiband indicato

4.8.13 Permitted Network Color Code (ncc permitted) I. Definition

During a talk, the MS must report the measured signals of neighbor cells to the base stat report the potential handover target neighbor cells, instead of reporting unselectively a

To enable previous functions, restrict MS to measure the cells with the fixed network co by MS. The MS compares the measured NCC of neighbor cells and NCCs set allowed by pa otherwise, the MS discard the measurement report. II. Format

The parameter ncc permitted is a bit mapping value, consisting of 8 bits. The most signi code 0 to 7 (see GSM regulations 03.03 and 04.08).

If the bit N is 0 (N ranges from 0 to 7), the MS needs not to measure the level of the cell corresponding to bit number of 1 in NCC and ncc permitted configuration. III. Configuration and Influence

Each area is allocated with one or more NCCs. In the parameter ncc permitted of the ce drop occur. For normal roaming between areas, the NCC of neighbor areas must be inclu IV. Precautions

Improper configuration of the parameter causes normal handover and even call drop. Th


Serial Parameters of Cell Selection and Reselection 4.3.1 cell_bar_access I. Definition

In the SI broadcasted in each cell, a bit indicates whether the MS is allowed to access th II. Format

The value of cell_bar_access includes 1 and 0. The value 0 indicates that MS is allowed t from the cell. Actually whether to allow MS to access the network from the cell is deter III. Configuration and Influence

The cell_bar_access is configured by equipment room operators. Usually the MS is allow the operators want some cell for handover service only, so cell_bar_access is configured

The MS usually works in microcells (you can configure the priority of cells and reselectio over to the base station G. The signals of base station G are stronger than microcell bas of microcell cells, the MS will not reselect a cell according to GSM regulations, therefore

The capacity of base station G is usually small, so the previous phenomenon leads to con forbid MS directly accessing base station G. In area A, handover is allowed to base statio IV. Precautions

The cell_bar_access is used only in some special areas. For common cells, it is configure

4.3.2 cell_bar_qualify I. Definition

The cell_bar_qualify determines the priority of cells, namely, it enables MS to select som II. Format

The value of cell_bar_qualify includes 1 and 0. The cell_bar_qualify and cell_bar_access Table 7-1 Cell priorities cell_bar_qualify

An exception is that the cell selection priority and cell reselection state are normal whe l The

cell belongs to the PLMN which the MS belongs to.

l The

MS is in cell test operation mode.

l The

cell_bar_access is 1.

l The

cell_bar_qualify is 0.

l The

access control class 15 is disabled.


The priority of all the cells are usually configured to normal, namely, cell_bar_qualify = by preference. In this situation, the equipment room operators can configure the priorit

During cell selection, when the proper cells with normal as the priority is not present (p cell is allowed to access), the MS will select cells with low priority. IV. Precautions Pay attention to the following aspects:

l When

cell priority is used as a method to optimize network, the cell_b network by combining cell_bar_qualify and C2. l During

cell selection, when the proper cells with normal as the priorit normal priority is low, and cells with low priority and high level are present,

4.3.3 Minimum Received Level Allowing MS to Access (RXLEV_ACCESS_MIN) I. Definition

To avoid bad communication quality, call drop, and a waste of network radio resources d MS accesses the network the received level must be greater than the threshold level, na II. Format The value range of RXLEV_ACCESS_MIN is from –110 dBm to –47 dBm. III. Configuration and Influence

The recommended RXLEV_ACCESS_MIN needs to be approximately equal to the receiving traffic adjustment and network optimization.

For cells with over high traffic and severe congestion, you can increase RXLEV_ACCESS_M must not configure RXLEV_ACCESS_MIN over great, because this might cause non-seamle smaller than or equal to –90 dBm. IV. Precautions

Except for areas of high density of base stations and of qualified coverage, adjusting cel

4.3.4 Additional Reselection Parameter Indicator I. Definition

The cell selection and reselection by MS depends on the parameters C1 and C2. Whethe parameter indicator (ADDITIONAL RESELECT) informs MS of whether to use C2 in cell res II. Format

ADDITIONAL RESELECT consists of 1 bit. In SI3, it is meaningless, and equipment manufac l When

ADDITIONAL RESELECT is configured to N, the meaning is: if the C2 and related cell reselection parameter PI. l When

ADDITIONAL RESELECT is configured to Y, the meaning is that the

III. Configuration and Influence Cells seldom use SI7 and SI8, so you can configure ADDITIONAL RESELECT to N. When cel RESELECT to Y.

4.3.5 Cell Reselection Parameter Indicator I. Definition

The cell reselection parameter indicator (CELL_RESELECT_PARAM_IND) is used in informi II. Format

The value of CELL_RESELECT_PARAM_IND includes Y and N, with the meanings as follows l Y:

The MS must calculate C2 by abstracting parameters from SIs of cel

l N:

The MS must set C1 as the standard, namely, C2 = C1.


The equipment room operators determine the value of PI. Configure PI to Y if related ce

4.3.6 Cell Reselection Offset, Temporary Offset, and Penalty Time I. Definition

After the MS selects a cell, without great change of all the conditions, the MS will camp l Starts

measuring signals level of BCCH carrier in neighbor cells.

l Records

the 6 neighbor cells with greatest signal level.

l Abstract

various SI and control information of each neighbor cell from

When conditions are met, the MS hands over from the selected cell to another. This proc l Cell

priority

l Whether l Radio

the cell is barred to access

channel level (important)

When the signal level of neighbor cells exceeds that of the serving cell, cell reselection 1) When PENELTY_TIME ≠ 11111:

C2 = C1 + CELL_RESELECT_OFFSET - TEMPORARY_OFFSET * H (PENALTY_TIME

Wherein, if PENALTY_TIME - T (x) < 0, the function H(x) = 0; if x ≥ 0, H(x) = 1 2) When PENELTY_TIME = 11111: C2 = C1 - CELL_RESELECT_OFFSET

T is a timer, with 0 as the initial value. When a cell is listed by MS in the list of cells wit list, the associated T is reset. After cell reselection, the T of original cell works as PENALTY_TIME. Namely, temporary CELL_RESELECT_OFFSET (CRO) modifies cell reselecting time C2.

TEMPORARY_OFFSET (TO) is supplemented to C2 from starting working of T to the prescr

PENALTY_TIME is the time for TEMPORARY_OFFSET having effect on C2. When PENALTY_T

CELL_RESELECT_OFFSET, TEMPORARY_OFFSET, and PENALTY_TIME are cell reselection pa l When l If

the cell reselection parameter PI is 1, the MS is informed of rec

PI is 0, the MS judges that the previous three parameters are 0, nam

If the C2 of a cell (in the same location area as the serving cell) calculated by MS is grea cell.

If the C2 of a cell (in different location area as the serving cell) calculated by MS is grea 5s, the MS reselects to camp on the cell.

The interval between two reselections is at least 15s, and this avoids frequent cell resel

C2 is formed on the combination of C1 and artificial offset parameters. The artificial off the network. II. Format

1) The cell reselection offset (CRO) is in decimal, with unit of dB. It rang

2) The temporary offset (TO) is in decimal, with unit of dB. It ranges from

3) The penalty time (PT) is in decimal, with unit of second. It ranges from the effect direction of C2 by CRO. The recommended value is 0. III. Configurationa and Influence The previous parameters can be adjusted accordingly in the following three situations:

1) When the communication quality is bad due to heavy traffic or other c For this situation, configure PT to 31, so TO is ineffective. C2 = C1 – CRO. Th equipment room operators can configure CRO to a proper value according to

2) For cells with low traffic and equipment of low utilization, change the dB according to the priority. The higher the priority is, the greater the CRO reselection, the recommended value of PT is 20s or 40s.

3) For cell with average traffic, configure CRO to 0, PT to 11111 so that C IV. Precautions

In whatever situations, the CRO must not be greater than 30 dB, because over great CRO

4.3.7 Cell Reselection Hysteresis (CRH) I. Definition

CRH affects cell reselection of cross location area. The MS starts cell reselection if the f l The

signal level of neighbor cell (in different location area) is greater

l The

difference between the signal levels of the neighbor cell and the

The difference is based on the cell reselection methods used by MS. If the MS reselects a II. Format

CRH is in decimal, with unit of dB. The range is 0 to 14, with step of 2 dB. The recomme III. Configuration and Influence

If the original cell and target cell belongs to different location areas, the MS must origin channels, the C2 of two cells measured at the bordering area of neighbor cells fluctuate rather short for location updating. The signal flow of network increases sharply, radio re

During location updating, the MS cannot respond to paging, so the connection rate decre updating of cross location area is frequent, the cell reselection hysteresis is increased a IV. Precautions Do not configure CRH to 0 dB

cell_bar_access

Cell selection priority

Cell reselection state

0 Normal

Normal

1 Barred

Barred

0 Low

Normal

1 Low

Normal


Frequency Hopping Parameters 4.5.1 Frequency Hopping Sequence Number I. Definition

In a GSM network, the cell allocation (CA) means the set of carriers used by each cell, re communication process, the set of carriers used by base station and MS is mobile allocat Obviously MA is a subset of CA.

During a communication process, the air interface uses a carrier number, one element o frequency hopping algorithm in GSM regulation 05.02, the MAI is the TDMA frame numbe allocation index offset (MAIO). Wherein, the HSN determines two aspects: l Track l The

of frequency points during frequency hopping

asynchronous neighbor cells using the same MA can avoid continuo

II. Format HSN is in decimal, ranging from 0 to 63, wherein: l 0:

cyclic frequency hopping

l 1–63:

pseudo frequency hopping


You can choose any HSN in cells using frequency hopping, but you must ensure that the c

In an 1X1 network, three cells under a base station use the same frequency group, but t plan MAIO properly to avoid frequency collision of the three cells under the same base s

4.5.2 Mobile Allocation I. Definition

The mobile allocation (MA) in the GSM network indicates a frequency set for frequency h performs transient in the set by MA according to rules. The parameter MA determines all the elements in MA. II. Format MA is a set, with all GSM frequency points as its element, namely: l For

GSM900 networks: 1–124 and 975–1023.

l For

GSM1800 networks: 512–885

III. Configuration and Influence MA is configured according to network designing requirements. IV. Precautions

Chinese GSM networks do not cover all available frequency bands of GSM system, so con The number of elements in each MA set cannot exceed 63. The MA cannot include BCCH carriers. The number of MA must not be multiples of 13 if all the following conditions are met: l Using l HSN

DTX

= 0 (cyclic frequency hopping)

You must avoid SACCH to appear usually at the same frequency point.

4.5.3 Mobile Allocation Index Offset I. Definition

During communication, the air interface uses a carrier frequency, one element of MA set regulation 05.02, the MAI is the TDMA frame number (RN) or reduced frame number (RFN initial offset of MAI, and it aims to avoid multiple channels to use the same frequency ca II. Format MAIO ranges from 0 to 63. III. Configuration and Influence MAIO is configured by equipment room operators. IV. Precautions The different cells using same group of MA must use consistent MAIO.

Using different MAIOs enables different sectors in the same location to use the same fre


This section introduces the methods to handle SDCCH congestion and TCH cong For this case, the real channels cannot be allocated to the MS, so the MS will fa I. Congestion Problem Solutions l Congestion caused by heavy traffic

You can check if the SDCCH traffic and TCH traffic are normal throug the capacity of the network. In addition, you can adopt traffic sharin l SDCCH congestion caused by burst traffic

If the SDCCH congestion rate is high and the traffic is heavy but the railways and tunnel exits, because the BTSs are installed in remote p of MSs failing to capture a network will perform location update, whi also occur easily. SDCCH congestion cannot be completely avoided, conversion between SDCCH and TCH. l Congestion caused by TRX problems

When a carrier configured in a multi-TRX cell cannot provide services problem cannot be positioned, you should check if the antenna feed l Congestion caused by interference The interference present across the radio interfaces will also cause c l Channel assignment failure caused by inconsistent coverage If the concentric technology is not used, the transmit power of the T will easily occur. To position this problem, you can check if the conne When a cell uses multiple transmitter antennas, inconsistent covera transmitter antenna as consistent as possible through engineering a In addition, if the transmitter antenna and the receiver antenna of a case, you can calibrate the antennas to solve the problem. l Congestion caused improper data configuration If the congestion is caused by improper location area planning, you c If the congestion is caused by the problems concerning SDCCH dyna For dual-band network, you can properly set the parameters (such a If the timers, such as T3101, T3103, T3107, T3122, T3212, and T311 Hereunder are the solutions to the previous problems. You can ease the congestion caused by SDCCH dual allocation throu time. To fully use the radio resources, therefore, you can reduce the You can save the TCH resources through reducing the T3103 and T31 The T3122 must be stopped once the MS receives an IMMEDIATE AS request messages frequently, the RACH load and CCCH load will incr T3212 stands for the time limit value for periodical location update. T3111 is related to release latency. It is used for the deactivation of value of T3111 must be consistent with that of the T3110 at the MS II. Congestion Cases Case 1: SDCCH congestion caused by wrong LAC configuration [Description] A BTS is configured as S1/1/1. It is found that the SDCCH congestion rate for 2 c [Problem analysis and solution] 1) Through checking the measurement indexes for TCH and SD However, the requests for SDCCH seizure are great, reaching 3032 t 2) The main reasons for SDCCH seizure include the messages s messages.

3) The TCH traffic is normal, the requests for TCH seizure (inclu may be caused by a large number of location update messages or sh 4) The LAC of the BTS is 0500, and the LACs of other cells of th busy hours were 298, the SDCCH traffic was 0.27Erl, and the conges Case 2: SDCCH congestion caused by burst location updates [Problem description] The radio connected ratio of a local network is lower than average level. Accord [Problem analysis and solution] 1) Through analyzing traffic statistics, engineers found that the cell was configured with 8 SDCCHs. Therefore, the SDCCHs can be se 2) As far as the registered traffic statistics items were concerne most of the BTSs were installed at the intersections of two railways.

3) To verify if it was the burst location update that caused the c the five seconds. Through querying the train time table, engineers fo location updates were generated in a short time. In this case, the co Therefore, if the BTSs are installed at the railway intersections, you are suggest Case 3: Great TCH congestion rate caused by the inconsistent tilt angl [Problem description] It is found that the TCH congestion rate of a cell is great (greater than 5%) acco [Problem analysis and solution] 1) Through checking BSC traffic statistics, engineers found that 2) Generally, TCH seizure failure is caused by TCH assignment f No.5 TRX, and the probability for the assignment failure rate for the

3) Through checking the antenna feeder part, engineers found antenna for BCCH, because the antenna nuts were found loosen. The to the MS when the MS starts a call, the TCH seizure failure will occu 4) To solve the problem, you can enable the tilt angel of the TC 2% or lower. Case 4: High TCH congestion rate caused by downlink interference [Problem description]

A cell of BTS is responsible for covering a large area of sea surface along the co congestion of the cell reached 10% at some time. However, no alarm was gene [Problem analysis and solution]

Because all the interference bands fell within the interference band1, the uplink present along the coast, the probability for the channel numbers of the downlin congestion rate was improved. Through further optimizing the channel numbers caused by the downlink interference of some areas.


Ha

The MS is always moving during conversation. To ensure channel quality, the M to the BSC through the service cell. The BSC will perform radio link control acco replace the old cell to ensure the continuity of the service. The handover enable I. Handover Problem Positioning Steps 1) Find out if the problem occurs at an individual cell or all cells co-BSC cells, or if they are co-MSC cells. If the handover between two cells fails, you should focus on checkin

If the problem is found in all the neighbor cells of a cell, you should f If the problem is found in all the cells under the same BSC, you shou If the problem is found in all the cells under the same MSC, the coop timer setting is irrational. 2) Check if the data has been modified before handover problem If the problem is found in an individual cell, you should focus on chec If the problem is found in all the cells under the same BSC, you shou If the problem is found in the cells under the same MSC, you should 3) Check if it is the hardware failure that causes the handover p

4) Register the related traffic statistics items, such as the hand l Check if the TCH seizure of the problem cell l Check if the outgoing handover success rate l Find out the causes for the handover failure. l Check if the radio handover success rate is n 5) Perform drive test for the problem cell and analyze the drive l Check if the uplink and downlink of the prob l Check if the measurement report for the pro l Check if a call can hand over from a problem l Analyze if the signaling procedure for the ha II. Handover Problem Analysis Methods i) Handover cannot be initiated If the MS is in a cell where the signal is poor, it cannot hand over to another cel Hereunder details the possible reasons: l The handover threshold is set to a low value

For edge handover, the handover triggering condition is that the Rxl the neighbor cells will be far higher than that of the service cell. In t resulted. The setting of the handover threshold depends on the cove l Neighbor cell relationship is not set

Though the signal level in the neighbor cells of the service cell is hig to a neighbor cell. Through performing cell reselection or dialing test found in the neighbor cell list, you should check if the correct neighb if the strong BCCH numbers are in the service cell or in the neighbor l Handover hysteresis is irrationally set If the difference between the signal level of the handover candidate to a too great value, the handover is hard to be initiated. l The best measurement time "N" and "P" are irrationally set During normal handover, the MS uses N-P rules to list the handover best cell. When there are two cells become the best cell alternately, the MS m values of N and P and reduce the measurement time to make the ha

If the landform and the ground objects of the service cell are quite c meet N-P rule, which will make the handover difficult. ii) Handover problem caused by hardware failure If the data configuration for the problem cell and the neighbor cells h caused by BTS hardware equipment. If the cells sharing the same base station with the cell have similar p

If the problem is found in only one cell under the base station, you s test the problems of this kind, you can disable some of the carriers. carrier or if the CDU and antenna feeder part related to this carrier f handover success rate will decrease. To check if the signaling flow of the cell is normal and if the uplink Rx means that the hardware equipment of the fails or serious interferen iii) Handover problem caused by irrational data configurat l For stand-alone networking mode, if the outgoing MSC or inc should also check if the data configuration for the opposite MSC and l For co-MSC networking mode, if the handover is performed w cooperation between the BSCs is normal, and then check if the data l If the abnormal handover is found at a cell only, you need to If the incoming handover of a cell is abnormal, you need first check low, or even the handover does not occur. If all the incoming handovers to this cell is abnormal, you should che and the data configured for other cells but is related to this cell. For If there is only one incoming handover to a cell is abnormal but othe should also check if the data configuration for the neighbor cells is c The methods to analyze the abnormal outgoing handovers are simila l Check the timers (such as T3105, Ny1, T3103, and T3142) re

T3105 indicates the interval for continuous PHYSICAL INFORMATION to be sent correct frame from the MS, the network will resend the PHYSICAL INFORMATION and T3105 must be greater than the sum of T3124 and delta ("delta" indicates MS cannot perform successful handover.

T3124 is a timer waiting for the PHYSICAL INFORMATION from the network side start T3124. Upon receiving a piece of PHYSICAL INFORMATION, the MS will stop 675ms. For other cases, the T3124 is set to 320ms. III. Handover Cases Case 1: No handover candidate cell is available due to CGI error [Problem description] The handover in an area is abnormal. When the MS moves from cell A to cell B, cell C, the MS hands over from cell A to cell C. [Cause analysis] If a cell can work as a service cell and can hand over to other cells, but the inco [Problem solution] 1) Use the test MS to lock the BCCH numbers of cell B. The call 2) Make a call after locking the BCCH umber of any neighbor ce is seen in the drive test software. 3) The handover procedure requires the MS detecting the neigh report, the BSC must make the handover decision. If the handover c 4) If the signals of cell B are far stronger than that of cell A and errors occur during the activation of the target cell TCH. 5) If the cell B works as the target cell but the TCH cannot be a cell, so the TCH cannot be activated and no handover command can 6) The CGI error is found in cell B through data checking. The h Case 2: Unbalanced path causes low handover success rate [Problem description]

The incoming BSC handover success rate is quite low for the two cells under a B [Cause analysis] Generally, if the data problems, such as CGI error or intra-frequency interferenc signals, the incoming BSC handover success rate is low. [Solution] 1) The cell data is found normal. 2) Through checking traffic statistics items, engineers found tha

3) Through drive test, engineers found that frequent handover made, call drop occurred immediately. During the handover, enginee originating calls failed. For the answering calls, they can be connecte

4) It is estimated that the CDU uplink channel loss is great, or t 5) After changing the CDU, engineers found that the incoming h Case 3: Improper antenna planning causes low handover success rate [Problem analysis] The handover success rate among the three cells under a BTS is quite low acco than 30%. [Cause analysis] Generally, low handover success rate is caused by board failure, handover data

[Solution] 1) The BTS hardware is normal and no alarm concerning hando

2) The BTS locates at the eastern side of a south-north road an directions and the open resident areas lying under a hill in the east r engineers concentrated the antenna azimuth angles of the three cel the coverage is provided by the side lobes and back lobes of the thre the three cells are poor and fluctuating greatly. In addition, since the why the frequent handover failure occurs. 3) After setting the azimuth angles of the three cells to 60°, 180 Case 4: Problems concerning the cooperation of different carriers' equ [Problem description]

There is a dual-band network in which the GSM900 MHz network and the GSM1 engineers found that the dual-band handover success rate was low; especially 80%. However, the success rate of the handover from the GSM900 MHz networ [Cause analysis] For a dual-band network, if the problems concerning the cooperation of differen supports Phase 2+ and EFR. [Solution] 1) Through using signaling analyzer to analyze the message flo Handover Reject message to the BSC of the GSM1800 MHz network 2) The MSC of the GSM1800 MHz network sent a Prepare Hando sent back an Abort message.

3) Because the success rate of the handover from GSM900 MHz message (from the GSM900 MSC to GSM1800 MSC) is half rate versi version 1, full rate version 2, and half rate version 1, which belong to 4) Through modifying the MSC data of the circuit MSC data at th Handover message (from GSM1800 MSC to GSM900 MSC) are full ra


Call Drop Problems For the GSM network, call drop is users' major worry and the call drop rate is an I. Call Drop Resasons and Solutions i) Call drop due to coverage reasons [Reason analysis] l Discontinuous coverage (dead zone) For a single BTS, the quality of the signals at the edge of the station another cell. In this case, the call drop occurs. If the landform of the coverage areas is complex or fluctuates greatl the signals will be barred. In this case, the coverage is discontinuous l Poor indoor coverage If the buildings in an area are densely populated, the signal attenuat thick, the penetration loss is great and the indoor signal level is low. l Isolated island effect

As shown in Figure 8-13, the service cell forms an isolated island due great). In this case, the MS still seizes the signals of the service cell define the neighbor cell C. At this time, if the MS still performs the h by neighbor cell A, it cannot find a suitable cell. In this case, the call l Small coverage If the coverage is too small, the hardware equipment of a cell may fa failure occurs (the power amplifier part). [Judgment methods]

First you should find out the areas where the coverage is inadequate according the drive test in a larger scope to check if the signal level and the handover are can employ the traffic statistics recorded at the OMC to check the BSC overall c drop rate. Furthermore, you can still make the analysis and judgment by referri some ones: l Power control performance measurement (to check if the me l Rxlev performance measurement (to check if the ratio of the l Cell performance measurement/inter-cell handover performa the mean Rxlev are too low) l Call drop performance measurement (to check if the signal le normal before call drop) l Defined neighbor cell performance measurement (to position l Undefined neighbor cell performance measurement (to check level exist) l Power control performance measurement (to measure the gr [Solutions] 1) Check the areas where the coverage is inadequate

You can find out the area where the coverage is inadequate through in mountain areas that cannot form seamless coverage, you can add can improve the coverage through other means. For example, you c BTS, change the antenna azimuth angle, change the antenna tilt, ch should also analyze if the call drop is caused by landforms. Generally market, underground railway entrance, underground parking lot, and micro cell to solve the coverage problem. 2) Ensure indoor call quality

To ensure indoor call quality, you should make sure that the outdoor signals, you can increase the maximum BTS transmit power, change angle, and change the antenna height, and so on. If the indoor call q consider adding BTSs. For improving the indoor coverage of office bu indoor antenna distribution system. 3) For the cells having no neighbor cells, you can configure the drop rate. To eliminate the isolation island effect, you can reduce the 4) Eliminate hardware problems

You can check if there are hardware problems and if the coverage area is too sm arises dramatically but all other indexes are normal, you should check if the ne the downlink problems may occur. For example, TRX problem, diversity unit pro the uplink fails, the outgoing handover failure rate of the old cell will be high.) ii) Call drop due to handover reasons [Reason analysis] l Irrational parameter configuration

If the signal level at the cross-area of two cells is quite low, the level handover threshold is too low, some MSs will hand over to the neigh higher than that of the service cell. If the signal level of the neighbo handover, the call drop will occur if no suitable cell is available for th l Incomplete neighbor cell definition If the neighbor cell definition is incomplete, the MS will hold the conv the edges of the cell but cannot hand over to a stronger cell. In this l Neighbor cells with same BCCH and same BSIC exist. l Traffic congestion If the traffic is unbalance, no TCH will be available in the target cell. l BTS clock lost synchronization If the BTS lost synchronization, the frequency offset will go beyond t if handover fails. l T3103 expiry

The T3103 will be started when the network sends a handover command. Upon handover or the message to remove the command, the T3103 will stop. T3103 to return to the old channel. If the T3103 is set to a too small value, the MS can case, call drop may occur during handover. [Judgment methods]

You can judge if the cells with low handover success rate, frequent re-establishm analyzing traffic statistics indexes. After the judgment, you can find out what ca downlink Rxlev can cause the handover; the uplink and downlink Rxqual can ca handover; call direct retry can cause handover; and also handover can be initia To check if the BTS clock runs normally, you can check if the any alarm is gener correct the BTS clock to eliminate clock problem. You can check if there is hand problem cell, you should perform drive near the cell for several times. Hereund l Inter-cell handover performance measurement (frequent han l Inter-cell handover performance measurement (frequent han l Undefined neighbor cell performance measurement (the und measurement report go beyond the standard) l Outgoing cell handover performance measurement (find out handover target cell) l Low incoming cell handover success rate; the cell handover p congested. l TCH performance measurement (the handover times are not handover happens too frequent) [Solution] 1) Check the parameters affecting the handover. For example, each handover threshold, each handover hysteresis, handover time, the handover candidate cell, and so on. 2) If the call drop is caused by unbalance traffic volume or if the available at the target BTS, you can solve the problem by adjusting t project parameters, such as antenna tilt and antenna azimuth angle the traffic volume, you can use CRO to guide the MS to camp on oth level priority to guide the MS to hand over to the idle cell. In addition directly. 3) Calibrate the problem BTS clock to enable the synchronizatio iii) Call drop due to interference reasons [Reason analysis]

If the MS receives strong same-frequency interference signals or strong neighbo the bit error rate will deteriorate. In this case, the MS cannot demodulate the B cannot receive the measurement report from the MS correctly. As a result, the c become poor, and call drop will occur. [Judgment methods] The interference may be from the network itself or the outside network, or it m The following methods can be used to position the interference. l Find out the the call cellsdrive might befor interfered through checking traffic l Perform test the areas that might be interfe according to user complaint. You can find out if there is a place wher through drive test tools. In addition, you can use a test MS to perform interfered. l Check the frequency planning to see if same-frequency inter in the area where the frequency is improperly planned. l Adjust the channel numbers that might be interfered to see i l Exclude the interference caused by equipment. l If the previous methods fail to eliminate the interference, you frequencies to find out the interfered channel number and the interf Hereunder lists several traffic statistics indexes used for interference analysis: l Interference band

You can check the uplink interference through analyzing the interfere appears at the interference bands 3-5, the interference is present. If the traffic volume grows. Generally, if it is outside interference, it is that the interference bands are reported to the BSC by the BTS TRX indication messages. If the current channel is busy and cannot repor consider the traffic volume for the measuring the interference bands l Rxlev performance measurement The Rxlev performance measurement provides the matrix relationsh level is high but the quality is poor, it means that the interference (s interference, and outside interference) is present at the channel num l Poor quality handover ratio The cell performance measurement, inter-cell handover performance performance measurement records the outgoing handover attempt t signal quality, it means that the interference is present. l Rxqual performance measurement It is related to the mean Rxlev and Rxqual during call drop. l Call drop performance measurement It records the mean Rxlev and Rxqual during call drop. l Frequent handover failures and frequent re-establishment fai It means that the interference may be present in the target cell. [Solutions] 1) Check the interfered road and the distribution of signal quali are concerned, you can adjust the BTS transmit power and antenna planning to avoid the interference. 2) Use DTX technology, frequency hopping technology, power c

These technologies can be used to reduce the system noise and enh is divided into uplink DTX and downlink DTX. In this case, the transm the system can also be reduced. However, you should adjust the DT neighbor cell relationship. When signals received by the MS are poor downlink DTX is enabled, the BTS will increase its transmit power aft however, the BTS will reduce its transmit power. In this case, the int interference is present near the BTS, the downlink DTX will deteriora its transmit power, the conversation quality will decrease or the call is low but the the interference signal is strong. 3) Solve equipment problems, such as the self-excitation of interference. 4) Exclude the outside interference. iv) Call drop due to antenna feeder reasons [Reason analysis]

l Engineering problem may be one of the reasons. For exampl inversely connected, the level of the uplink signal will be far poorer t call drop, one-way audio, and call difficulty will be found in the areas l If polarization antennas are used, a cell had two sets of anten inconsistent with each other, the call drop will occur.

If a directional cell has a master antenna and a diversity antenna, th transmitted through the two antennas respectively. If the tilt angles scope of the two antennas will be different. In this case, the MS can when starting a call. Thus the call drop is resulted. l If the azimuth angles of the two antennas are inconsistent w MS can receive the SDCCH signals, but it may be assigned with the T l The problems concerning antenna feeder will also cause call water penetrates into the antenna, or connector problem is present, will decrease. In this case, the call drop will occur. To confirm the pro [Problem positioning and solution] 1) Check if any alarm concerning the combiner, CDU, tower am the BTS boards are normal in the OMC. 2) Analyze if the path balance is realized according to traffic sta 3) Further analyze if the path balance is realized through moni 4) Perform drive test and dialing test. During drive test, you can consistent with the planned ones, namely, if the transmit antenna of 5) Check and test the on-site BTSs. Here the installation of the must be checked. In addition, you should also check if the feeder an connector problem, and if the feeder is damaged. Furthermore, you

6) Judge if it is BTS hardware that causes path unbalance and c change the components that may have problems or disable other TR position the problem through dialing test. Once a problem hardware sound one. If no sound one is available, you must shut down the pro affecting network quality. Hereunder lists several traffic statistics items for path balance analysis: l Path balance measurement (to analyze if the path balance is l Call drop performance measurement (to analyze the uplink a l Power control performance measurement (to analyze mean R v) Call drop due to transmission reasons If the transmission quality across the Abis interface and A-interface may be not methods can be used to solve the problem:alarm and board alarm and analyze i 1) Check the transmission failure. 2) Check the transmission channel, test the bit error rate, chec grounding is rational to ensure stable transmission quality and reduc 3) Check the traffic statistics to see if the frequent call drop is c should check TCH performance measurement, because it can indicat normal, if the TCH utilization is normal, and if the ground link call dro vi) Call drop due to parameter reasons Here you should focus on checking if the parameters related to call drop are irra irrationally set, the call drop may be resulted. l Radio link failure counter

This parameter acts on the downlink. When the MS fails to decode th to disconnect the call. If this parameter is set to a too small value, th drop. For dead zones or the areas where the call drop frequently hap to a greater value. When changing the radio link failure counter, you should change the value great enough for the MS to detect a radio link failure. For exam 16 (about 8 seconds), the value of T3109 must be greater than 8 sec seconds). l SACCH multiframe number This parameter acts on the uplink. The BTS uses this parameter to n BSS. The BSS side judges the radio link failure according to the bit er set to a too small value, the radio link failure will happen frequently

l Access control parameters The access control parameters include the Minimum RACH Rxlev, RA parameters are irrationally set, the call drop will be easily resulted. l T3101, T3107 T3101 is started when the BSC sends a CHANNEL ACTIVATE message INDICATION message is received. This timer monitors the immediate allocated channels will be removed. T3107 is started when the BSC sends an ASSIGNMENT COMMAND m ASSIGNMENT COMPLETE message from the BTS, this timer will reset that the MS can return to the old channel. Or it can also be used by t If the two timers are set to a too small value, the system will not hav message to the BSC. In this case, the call drop will occur if the timer l T200; N200

T200 is an important timer used for the LAPDm (Link Access Procedu from occurring when the data is transferred across the data link laye radio interfaces can be divided into two types: the messages needin needing opposite acknowledgement.

For the messages needing opposite acknowledgement, a T200 must opposite acknowledgement is not received after a period of time, th timer must be restarted. If the retransmission times exceed the max retransmitted and the link will be released. That is, this call drops. N T200 and N200 have different types depending on channel types (TC types (signaling and given channel and service The call drop rate canmessages). be reducedThe if the message is type retransmitted as

acknowledgement is received. That is, the value of T200 must be se be set as great as possible. However, the T200 cannot be set to a to large value. If the opposite party has acknowledged that the link had nonsense. Therefore, to reduce the call drop rate, you can adjust the T200 and II. Call Drop Cases Case 1: Call drop caused by frequency hopping collision [Problem analysis] A BTS uses 1 x 3 RF frequency hopping. After capacity expansion, the TCH alloc problems. In addition, the TCH call drop rate and incoming handover failure rate [Problem positioning and solution]

Because high call drop rate and high incoming handover failure rate come toge that the problem may arise during TCH assignment or the channel numbers or t unstable. Because the SDCCH call drop rate is normal, it can be judged that the numbers to the interfered are small, but the non-BCCH carriers and non-BCCH n

Through checking the hardware, antenna feeder, and transmission, engineers f found that the signal level was high but the quality was poor. Through on-site d quality was poor. Through checking engineering parameters, engineers found th that of the old carrier. Therefore, it can be judged that the call drop was caused the MAIO, engineers found that call drop rate became normal. Case 2: Call drop caused by isolated island effect [Problem description] Users complained that call drop always occurred above the fifth floor of a buildi [Problem analysis] 1) Through on-site test, engineers found that call drop and nois it was always in the service area of the other BTS (hereunder called BTS C) before the call drop. 2) It is estimated that the service cell belongs to BTS B, which i it can be judged that the signals from the BTS B are reflected signals formed. 3) Through checking data configuration, engineers found that o relationship with BTS B. Therefore, when the MS is using the signals were strong, and if the cell 2 of BTS B has no neighbor cell relationsh be performed.

The signals from the cell 2 of BTS B are reflected many times. There became poor dramatically, emergent handover may be initiated. In t BTS A is not an ideal candidate cell for the cell 2 of BTS B. As a resul called BTS C), but the MS cannot receive the signals from BTS C. The [Solution] You are recommended to change the data in the BA1 (BCCH) list, BA2 (SACCH) you can configure the cell 3 of BTS A as the neighbor cell of cell 2 of BTS B. To e further optimize the engineering parameters. After that, the call drop problem c Case 3: Reduce call drop rate through optimizing handover parameter [Problem description] The drive test in an area found that the call drop rate at a cave near the BTS hi due time. [Problem The cave isanalysis near the and BTS. solution] The signal level of the target cell is about -80dBm in below -100dBm. The downlink power of the two cells outside the cave is good, signal level deteriorates dramatically in the cave, so the call drop occurs before To reduce the call drop you can optimize adjust the handover parame 1) If no rate, ping-pong handover is and present and the conversation is happen as easily as possible. 2) Set the threshold to trigger the emergent handover rationall before call drop. For the parameter modification, see Handover parameter optimization Parameter Name PBGT handover measurement time PBGT handover duration PBGT handover threshold Uplink quality threshold for emergent handover Minimum downlink power for handover candidate cell

Case 4: Call drop caused by clock problem [Problem description] The cell A of an 1800MHz network has been cutover. After the establishment of over to the GSM900 MHz cell that shares the same BTS site drops in the GSM90 [Problem analysis and solution] established on the GSM1800 MHz cell intend to hand over to the GSM900 MHz c dramatically first, and then gradually disappears to none. If the handover is from phenomenon is also present. Through monitoring signaling, engineers find that call drop is just process for call re-establishment. However, the test MS shows t MHz cell. Therefore, it can be judged that the clocks are seriously asynchronous the GSM900 equipment provider cooperate with each other on clock calibration Therefore, for dual-band handover, the clock of the GSM900 MHz BTS and that

Before Modification

After Modification


Power 4.9.1 Maximum Transmit Power of MS (MSTXPWRMX) I. Definition The transmit power of MS in communication is controlled by BTS. According to t & Note:

In any situation, power control is prior to related handover for BSS. Only when t

To reduce interference between neighbor cells, the power control of MS is restri MSTXPWRMX is the maximum transmit power of MS controlled by BTS. II. Format MSTXPWRMX ranges from 0 to 31. The dBm values corresponding to GSM900 and GSM1800 cells are different: l The 32 maximum transmit power control classes for GSM900 l The 32 maximum transmit power control classes for GSM900 III. Configuration and Influence Configuring MSTXPWRMX helps control interferences between neighbor cells, b l If MSTXPWRMX is over great, the interference between neigh l If MSTXPWRMX is over small, the voice quality declines and i 4.9.2 Received Level Threshold of Downlink Power Increment (LDR) I. Definition

When the downlink received level of the serving cell is smaller than a threshold The received level threshold of downlink power increment defines the downlink transmit power. The parameter N1 means that at lease N1 sampling points must be measured b The parameter P1 means the level of at least P1 sampling points in N1 samplin II. Format It ranges from –110 dBm to –47 dBm. N1 ranges from 1 to 32. P1 ranges from 1 to 32. III. Configuration and Influence The received level is between –60 dBm and –80 dBm in a GSM network, so confi N1 is related to propagation quality of radio channels within cell coverage range Configure P1 to about 2/3 of N1. 4.9.3 Received Level Threshold of Uplink Power Increment (LUR) I. Definition When the uplink received level of the serving cell is smaller than a threshold, th The received level threshold of uplink power increment defines the uplink recei transmit power. The parameter N1 means that at lease N1 sampling points must be measured b The parameter P1 means the level of at least P1 sampling points in N1 samplin II. Format It ranges from –110 dBm to –47 dBm. N1 ranges from 1 to 32. P1 ranges from 1 to 32. III. Configuration and Influence The received level is between –60 dBm and –80 dBm in a GSM network, so confi N1 is related to propagation quality of radio channels within cell coverage range Configure P1 to about 2/3 of N1. 4.9.4 Received Quality Threshold of Downlink Power Increment (LDR) I. Definition

When the downlink received quality of the serving cell is smaller than a thresho The received quality threshold of downlink power increment defines the downlin increase its transmit power.

The parameter N3 means that at lease N3 sampling points must be measured b The parameter P3 means the quality of at least P3 sampling points in N3 sampl II. Format It ranges from 0 to 7, the voice quality grade. N3 ranges from 1 to 32. P3 ranges from 1 to 32. III. Configuration and Influence The received quality is 0 to 2 of quality grade in a GSM network, so configure re N3 is related to propagation quality of radio channels within cell coverage range Configure P3 to about 2/3 of N3. 4.9.5 Received Quality Threshold of Uplink Power Increment (LUR) I. Definition When the uplink received quality of the serving cell is smaller than a threshold, The received quality threshold of uplink power increment defines the uplink rec transmit power of MS. The parameter N3 means that at lease N3 sampling points must be measured b The parameter P3 means the quality of at least P3 sampling points in N3 sampl II. Format It ranges from 0 to 7, the voice quality grade. N3 ranges from 1 to 32. P3 ranges from 1 to 32. III. Configuration and Influence The received quality is 0 to 2 of quality grade in a GSM network, so configure re N3 is related to propagation quality of radio channels within cell coverage range Configure P3 to about 2/3 of N3. 4.9.6 Received Level Threshold of Downlink Power Decrement (UDR) I. Definition

When the downlink received level of the serving cell is greater than a threshold The received level threshold of downlink power decrement defines the downlink its transmit power. The parameter N2 means that at lease N2 sampling points must be measured b The parameter P2 means the level of at least P2 sampling points in N2 samplin II. Format It ranges from –110 dBm to –47 dBm. N1 ranges from 1 to 32. P1 ranges from 1 to 32. III. Configuration and Influence The received level is between –60 dBm and –80 dBm in a GSM network, so confi N2 is related to propagation quality of radio channels within cell coverage range Configure P2 to about 2/3 of N2. 4.9.7 Received Level Threshold of Uplink Power Decrement (UUR) I. Definition When the uplink received level of the serving cell is greater than a threshold, th The received level threshold of uplink power decrement defines the uplink rece power of MS. The parameter N2 means that at lease N2 sampling points must be measured b The parameter P2 means the level of at least P2 sampling points in N2 samplin II. Format It ranges from –110 dBm to –47 dBm. N2 ranges from 1 to 32. P2 ranges from 1 to 32. III. Configuration and Influence The received level is between –60 dBm and –80 dBm in a GSM network, so confi N2 is related to propagation quality of radio channels within cell coverage range Configure P2 to about 2/3 of N2. 4.9.8 Received Quality Threshold of Downlink Power Decrement (UDR)

I. Definition When the downlink received quality of the serving cell is greater than a thresho The received quality threshold of downlink power decrement defines the downli decrease transmit power of MS. The parameter N4 means that at lease N4 sampling points must be measured b The parameter P4 means the quality of at least P4 sampling points in N2 sampl II. Format It ranges from 0 to 7, the voice quality grade. N4 ranges from 1 to 32. P4 ranges from 1 to 32. III. Configuration and Influence The received quality is 0 to 2 of quality grade in a GSM network, so configure re N4 is related to propagation quality of radio channels within cell coverage range Configure P4 to about 2/3 of N4. 4.9.9 Received Quality Threshold of Uplink Power Decrement (UUR) I. Definition When the uplink received quality of the serving cell is greater than a threshold, The received quality threshold of uplink power decrement defines the uplink rec transmit power of MS. The parameter N4 means that at lease N4 sampling points must be measured b The parameter P4 means the quality of at least P4 sampling points in N4 sampl II. Format It ranges from 0 to 7, the voice quality grade. N4 ranges from 1 to 32. P4 ranges from 1 to 32. III. Configuration and Influence The received quality is 0 to 2 of quality grade in a GSM network, so configure re N4 is related to propagation quality of radio channels within cell coverage range Configure P4 to about 2/3 of N4. 4.9.10 Power Control Interval (INT) I. Definition It takes a period from beginning of power control to detection of effect of power call drop occurs. The parameter power control interval (INT) configures the minimum interval be II. Format It ranges from 0 to 31s. III. Configuration and Influence According to frame structure of GSM network, configure INT to about 3s. IV. Precautions INT cannot be smaller than 1s, and otherwise the system becomes unstable. 4.9.11 Power Increment Step (INC) I. Definition The INC indicates the power increment of MS or base station in power control. II. Format The range of INC is 2 dB, 4 dB, or 6 dB. III. Configuration and Influence The recommended value is 4 dB. 4.9.12 Power Decrement Step (RED) I. Definition The RED indicates the power decrement of MS or base station in power control. II. Format The range of RED is 2 dB or 4 dB. III. Configuration and Influence The recommended value of RED is 2 dB.

Click to return to main page Checking the Parameter Settings for DCR Huawei 2G The parameter settings on the BSC side and MSC side may affect the TCH call drop rate. You should check the settings of the following parameters for a cell with a high TCH call drop rate. See Case 5: Reduction of Call Drops by Optimizing Handover Parameters and Case 12: Increase in Call Drop Rate Due to Change of TR1N on the MSC Side. 1. SACCH Multi-Frames This parameter determines whether an uplink radio link is faulty. Each time the BTS fails to decode the measurement report on the SACCH from the MS, the counter decreases by 1. Each time the BTS successfully decodes the measurement report on the SACCH, the counter increases by 2. When the value of this counter is 0, the BTS regards the radio link as faulty. In the traffic measurement, if there are many call drops (M3101A) related to radio link failure, you can infer that the radio propagation conditions are poor. In this case, you can set this parameter to a greater value. 2. Radio Link Timeout This parameter determines whether a downlink radio link is faulty. Each time the BTS fails to decode the measurement report sent over the SACCH by the MS, the counter decreases by 1. Each time the BTS successfully decodes the measurement report sent over the SACCH, the counter increases by 2. When the value of this parameter is 0, the BTS regards the radio link as faulty. In the traffic measurement, if there are many call drops (M3101A) related to radio link failure, you can infer that the radio propagation conditions are poor. In this case, you can set this parameter to a greater value. 3. RXLEV_ACCESS_MIN This parameter specifies the minimum receive level of an MS to access the BSS. If this parameter is set to a too small value, some MSs with low receive levels may access the network and call drops are likely to occur. You can set this parameter to a great value to reduce the TCH call drop rate. The counters such as call setup success rate and the counters related to traffic volume, however, are accordingly affected. 4. RACH Min.Access Level This parameter determines whether an MS can access the network over the RACH. If this parameter is set to a too small value, some MSs with low signal levels may access the network and call drops are likely to occur. You can set this parameter to a great value to reduce the TCH call drop rate. The counters such as call setup success rate and paging success rate, however, are affected. 5. Min DL Power on HO Candidate Cell and Min Access Level Offset The sum of the values of the two parameters specifies the minimum downlink receive level of a candidate neighboring cell for a handover. If this parameter is set to a too great value, some desired cells may be excluded from the candidate cells; if this parameter is set to a too small value, an unwanted cell may become the candidate cell. Both conditions may lead to the increase of call drops. 6. Timer T3103 series

Timer T3101 series consists of T3103A, T3103C, and T8. These timers are started to wait for a handover complete message. If the lengths of the timers are set to small values, probably no message is received when timer T3103 series expires. In this case, the BSC considers that the radio link in the originating cell is faulty. Then, the BSC releases the channel in the originating cell. Thus, call drops occur. In the traffic measurement, if many call drops are related to handovers (CM331: Call Drops on Radio Interface in Handover State), you can set this parameter to a greater value. If this parameter is set to a too great value, channel resources are wasted and measurement report on the SACCH, the counter increases by 2. When the value of this counter is 0, the BTS regards the radio link as faulty. In the traffic measurement, if there are many call drops (M3101A) related to radio link failure, you can infer that the radio propagation conditions are poor. In this case, you can set this parameter to a greater value. 7. Timer T3109 This parameter specifies the period for waiting for a Release Indication message after the BSC sends a Channel Release message to the BTS. If this parameter is set to a too small value, the link may be released before the Release Indication message is received. As a result, a call drop occurs. You can set this parameter to a greater value to reduce the TCH call drop rate. It is recommended that timer T3109 be set to 1–2 seconds longer than timer Radio Link Timeout. 8. Timer T3111 This parameter specifies the interval between the time that the main signaling link is disconnected and the time that a channel is deactivated. The purpose is to reserve a period of time for repeated link disconnections. If this timer is set to a too small value, a channel may be deactivated too early. Thus, call drops increase. 7. Timer T3109 This parameter specifies the period for waiting for a Release Indication message after the BSC sends a Channel Release message to the BTS. If this parameter is set to a too small value, the link may be released before the Release Indication message is received. As a result, a call drop occurs. You can set this parameter to a greater value to reduce the TCH call drop rate. It is recommended that timer T3109 be set to 1–2 seconds longer than timer Radio Link Timeout. 8. Timer T3111 This parameter specifies the interval between the time that the main signaling link is disconnected and the time that a channel is deactivated. The purpose is to reserve a period of time for repeated link disconnections. If this timer is set to a too small value, a channel may be deactivated too early. Thus, call drops increase. 11. Call Reestablishment Forbidden This parameter specifies whether to allow call reestablishment. In case of burst interference or radio link failure due to blind areas caused by high buildings, call drops occur. In this case, MSs can initiate the call reestablishment procedure to restore communication. To reduce the TCH call drop rate, you can set this parameter to No to allow call

reestablishment. In certain conditions, allowing call reestablishment greatly reduces the TCH call drop rate. Call reestablishment lasts for a long time, and therefore some subscribers cannot wait and hang up. This affects user experience. 12. Parameters related to edge handover When the receive level drops greatly, an edge handover cannot be performed in time in any of the following conditions: The parameter Edge HO UL RX_LEV Threshold or Edge HO DL RX_LEV Threshold is set to a small value; the parameter Inter-cell HO Hysteresis is set to a great value; the parameters Edge HO Watch Time and Edge HO AdjCell Watch Time are set to great values; the parameters Edge HO Valid Time and Edge HO AdjCell Valid Time are set to great values. As a result, a call drop occurs. To reduce the TCH call drop rate, you can appropriately set these parameters so that edge handovers can be performed in time to avoid call drops. 13. Parameters related to BQ handover When the signal quality deteriorates, a BQ handover cannot be performed in time in any of the following conditions: The parameters ULQuaLimitAMRFR, ULQuaLimitAMRHR, UL Qual. Threshold, DLQuaLimitAMRFR, DLQuaLimitAMRHR, and DL Qual. Threshold are set to great values; the parameter BQ HO Margin is set to a small value; the parameter Inter-cell HO Hysteresis is set to a great value. As a result, call drops occur. To reduce the TCH call drop rate, you should appropriately set these parameters so that BQ handovers can be performed in time to avoid call drops. 14. Parameters related to interference handover If the parameters RXQUAL1 to RXQUAL12 are set to great values or if the RXLEVOff parameter is set to a great value, strong interference may occur. In this case, if interference handovers are not performed in time, call drops occur. To reduce the TCH call drop rate, you can appropriately set these parameters so that interference handovers can be performed in time to avoid call drops. If the parameters RXQUAL1 to RXQUAL12 are set to small values, the number of handovers due to other causes increases greatly, thus affecting the handover success rate. 15. Parameters related to concentric cell handover A call at the edge of the overlaid subcell cannot be handed over to the underlaid subcell in any of the following conditions: In the case of a normal concentric cell, the parameters RX_LEV Threshold and RX_LEV Hysteresis are set to great values; in the case of an enhanced concentric cell, the parameter OtoU HO Received Level Threshold is set to a great value. As a result, a call drop is likely to occur. If the Call Drop Ratio on TCH on the TRX in the OverLaid Subcell (RM330a) is high, you can appropriately set these parameters so that calls at the edge of the overlaid subcell can be handed over to the underlaid subcell in time. When a call in the underlaid subcell has interference, the call cannot be handed over to the overlaid subcell if the RX_QUAL for UO HO Allowed parameter is set to Yes and the RX_QUAL Threshold parameter is set to a great value. Thus, a call drop occurs. If the Call Drop Ratio on TCH on the TRX in the Underlaid Subcell (RM330) is high, you can set these

parameters properly so that the call can be handed over to the overlaid subcell at the earliest. 16. Parameters related to power control If the power control level and quality threshold are set to small values, call drops are likely to occur because of low signal level or bad voice quality. 17. T200 and N200 If the parameters T200 FACCH/F, T200 FACCH/H, N200 of FACCH/Full rate, and N200 of FACCH/Half rate are set to small values, data links are disconnected too early. Thus, all drops are likely to occur. If call drops occur because of T200 expiry, you can increase the values of T200 and N200 properly. 18. Neighboring cell relations If the neighboring cells configured in the BA2 table are incomplete, call drops are likely to occur in the case of no suitable neighboring cell for handover and progressive deterioration in the voice quality. Neighboring cell relations should be configured completely on the basis of the drive test data and electronic map (for example, Nastar) to minimize the call drops due to no available neighboring cells. 19. MAIO If frequency hopping (FH) is applied in a cell and the MAIO is set inappropriately (for example, different TRXs serving the same cell have the same MAIO), frequency collision may occur during FH. Thus, the TCH call drop rate increases. 20. Disconnect Handover Protect Timer This parameter is a software parameter of the BSC. After receiving a DISCONNECT message from an MS, the BSC cannot hand over the MS within the period specified by this parameter. Therefore, the following case can be avoided: After being handed over to the target cell, the MS cannot be put on hook because it does not receive a release acknowledgement message. You are advised to set this parameter properly. 21. TR1N This parameter should be set on the MSC side. It is used to avoid the retransmission of short messages. When this parameter is set to a too great value, the MSC does not send a CLEAR CMD message if the MS receives a short message during link disconnection. As a result, the MS sends the BTS a DISC message to disconnect layer 2 connection. After receiving the DISC message, the BTS sends a REL_IND message to the BSC. Then, the BSC sends a CLEAR REQ message to the MSC and the number of call drops is incremented by one. 22. Software Parameter 13 and MAX TA When the parameter Software Parameter 13 is enabled and the parameter MAX TA is set to a too small value, the channel is released when the TA of a call exceeds the MAX TA. In this case, call drops occur. It is recommended that the parameter Software Parameter 13 should not be enabled. 23. Directly Magnifier Site Flag If a BTS is installed with repeaters, the handover between repeaters can only be asynchronous because the distance between repeaters is long. If synchronous handovers are performed, the handovers may fail and thus many

call drops occur. Therefore, when a BTS is installed with repeaters, the parameter Directly Magnifier Site Flag should be set to Yes to avoid synchronous handovers between cells under the same BTS.


Vendor Huawei Huawei Huawei Huawei Huawei Huawei Huawei

Tech 3G 3G 3G 3G 3G 3G 3G

Resource Type UL CE DL CE UL Power DL Power UL IuB DL IuB Code

NSN

3G

UL CE

NSN NSN NSN NSN NSN Huawei Huawei

3G 3G 3G 3G 3G 2G 2G

DL CE UL Power DL Power IuB Code SDCCH TCH

Huawei

2G

TBF

Huawei

2G

PDCH

Huawei Nokia Nokia Nokia Nokia Siemens

2G 2G 2G 2G 2G 2G

Abis SDCCH TCH PDCH Abis SDCCH

Siemens Siemens Siemens

2G 2G 2G

TCH PDCH Abis

Congestion Counter VS.RRC.Rej.ULCE.Cong+VS.RAB.FailEstabCS.ULCE.Cong+VS.RAB.FailEstabPS.ULCE.Cong VS.RRC.Rej.DLCE.Cong+VS.RAB.FailEstabCS.DLCE.Cong+VS.RAB.FailEstabPS.DLCE.Cong VS.RRC.Rej.ULPower.Cong+VS.RAB.FailEstabCS.ULPower.Cong+VS.RAB.FailEstabPS.ULPower.Cong VS.RRC.Rej.DLPower.Cong+VS.RAB.FailEstabCS.DLPower.Cong+VS.RAB.FailEstabPS.DLPower.Cong VS.RRC.Rej.ULIUBBand.Cong+VS.RAB.FailEstabCS.ULIUBBand.Cong+VS.RAB.FailEstabPS.ULIUBBand.Cong VS.RRC.Rej.DLIUBBand.Cong+VS.RAB.FailEstabCS.DLIUBBand.Cong+VS.RAB.FailEstabPS.DLIUBBand.Cong

VS.RRC.Rej.Code.Cong+VS.RAB.FailEstabCS.Code.Cong+VS.RAB.FailEstabPS.Code.Cong rrc_conn_stp_fail_bts+rab_stp_fail_cs_voice_bts+rab_stp_fail_ps_strea_bts+rab_stp_fail_ps_inter_frozbs+rab_ _str_1+setup_fail_bts_hs_dsch_bgr rrc_conn_stp_fail_bts+rab_stp_fail_cs_voice_bts+rab_stp_fail_ps_strea_bts+rab_stp_fail_ps_inter_frozbs+rab_ _str_1+setup_fail_bts_hs_dsch_bgr rrc_conn_stp_fail_ac+rab_stp_fail_cs_voice_ac+rab_stp_fail_ps_strea_ac +rab_stp_fail_ps_inter_ac+rab_stp_fa rrc_conn_stp_fail_ac+rab_stp_fail_cs_voice_ac+rab_stp_fail_ps_strea_ac +rab_stp_fail_ps_inter_ac+rab_stp_fa rrc_conn_stp_fail_iub_aal2+rab_stp_fail_cs_v_iub_aal2+setup_fail_iub_hs_total_str_1+setup_fail_iub_hs_total_ rrc_conn_stp_fail_ac+rab_stp_fail_cs_voice_ac+rab_stp_fail_ps_strea_ac +rab_stp_fail_ps_inter_ac+rab_stp_fa K3001:Failed SDCCH Seizures due to Busy SDCCH K3011A:Failed TCH Seizures due to Busy TCH (Traffic Channel)

[A9003:Number of Failed Uplink GPRS TBF Establishments due to No Channel] +[A9203:Number of Failed Uplink EGPRS TBF Establishments due to No Channel]+[A9103:Number of Failed D Channel] +[A9303:Number of Failed Downlink EGPRS TBF Establishments due to No Channel]}

[R9394:Number of PDCH Application Failures due to no Convertable TCHs]+[R9395:Number of PDCH Applica [R9346:Number of Dynamic PDCH Requests Without Application Attempts Because the Number of Activated [R9347:Number of Dynamic PDCH Requests Without Application Attempts Because No Abis Timeslot is Availa R9347:Number of Dynamic PDCH Requests Without Application Attempts Because No Abis Timeslot is Availa

100 * ([SDCCH_BUSY_ATT] - [TCH_SEIZ_DUE_SDCCH_CON])/[SDCCH_SEIZ_ATT]) 100 * ([TCH_REQUESTS_CALL_ATTEMPT] - [SUCC_TCH_SEIZ_CALL_ATTEMPT])/[TCH_REQUESTS_CALL_ATTEMP 100 * ([NO_RADIO_RES_AVA_DL_TBF] + [NO_RADIO_RES_AVA_UL_TBF])/([NBR_OF_DL_TBF] + [NBR_OF_UL_TB dl_tbfs_with_inadeq_edap_res + ul_tbfs_without_edap_res ATSDCMBS / NATTSDPE (ATCHSMBS_1 + ATCHSMBS_2) /(ATTCHSEI_1 +ATTCHSEI_2) --> excluding A-bis blocking (ATCHSMBS_1 + ATCHSMBS_2 + ATCHSMBS_3 + ATCHSMBS_4) /(ATTCHSEI_1 +ATTCHSEI_2) --> including A-b REJPDASS_1..37 / (NUACATCL_3 + NUACATCL_6) ABISPSUP[7]/(ABISPSUP[6] + ABISPSUP[7])

Click to return to main page Case CE Blocking/CE High Util Iub Blocking/Iub High Util DL- Power Blocking/DL - Power High Util UL- Power Blocking Code Blocking

1st Action Check trending of CE Availability Physical Audit (involving TP analysis) Physical Audit (involving TP analysis) Physical Audit (involving TP analysis) Physical Audit (involving TP analysis)

2nd Action Physical Audit (involving TP analysis) IuB VC Split Activate 40W, maintain existing PCPICH setting Increase PrxTarget, adjust DeltaPrxMaxUp,DeltaPrxMaxDown Decrease used MaxBitrateDLPSNRT (128 kbits/s, 64 kbits/s)

3rd Action CE license and/or board upgrade Iub BW upgrade Increase PtxTarget, PtxMaxHSDPA

Click to return to main page Type

CS Blocking & Non PS blocking

PS Blocking & Non CS blocking

CS Blocking & PS blocking

2G/3G reselection ( traffic share)

Blocking

SDCCH blocking & Non TCH Blocking

TCH Blocking & Non SDCCH blocking

TCH Blocking & SDCCH blocking

PS Blocking ->due to no Convertable TCHs

PS Blocking->due to CELL PDCH Ratio Thresh PS Blocking->due to Activated PDCHs Reaches Board Specification PS Blocking->Abis Timeslot is Available for Use

First step check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis IP capacity problem)

check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis IP capacity problem)


check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis IP capacity problem) check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis IP capacity problem)


Second step 1.reduce MS MAX Retrans 2.Increase CRH (LAC border area) 3.Add fix SDCCCH channel 4.RACH Busy Threshold 5.ReduceCS RACH Min. Access Level 6.SDDYN->Yes (SDCCH Dynamic Allocation Allowed) 1.Enable TCH Rate Adjust Allow 2.Reduce TCHBUSYTHRES &AMRTCHHPRIORALLOW&AMRTCHHPRIORLOAD 3.Change SDCCH &PDCH to TCH channel 4.Enable load handover 5.PT & CRO 6.Counter A312F,TDM-> Reduce idle TS & upgrade Abis;IP mode upgrade Abis 1.same as upper reduce SDCCH & TCH blocking 2.PT &C CRO 3.Power adjust ( increase adjcent cells power type if possble) 4.upgrade TRX 1.Add fix PDCH channel 2.UPDYNCHNTRANLEV & DWNDYNCHNTRANLEV(20->70,20>80) 3.DYNCHFREETM(20->15) 1.Increase MAX PDCH rate threshold 2.PDCHUPLEV & PDCHDWNLEV(20->70,20->80) 3.DYNCHFREETM(15->10) DSP Re-balance Abis upgrade (IP mode increase BW) 1.Upgrade TRX or Abis transmission capacity 2.If upgrade limit,change PDCH to TCH (CS high priority) 3.Load sharing to 3G, FDD Qmin (7-->6[max -14db]) & SSEARCHRAT (2-->0) 1.Inter-RAT Cell Reselection Enable(IRAT reseclection) 2.Qsearch C Initial(seach 3G in Idle mode) 3.Qsearch I(7=always seach 3G) 4.FDD Qmin (3G candidate cells EC/NO threshold) 5.FDD Qmin Offset(candidate cells EC/NO offset)


Blocking


CS Blocking & Non PS blocking TCH Blocking & Non SDCCH blocking


PS Blocking, TCH not Blocking PS Blocking & Non CS blocking PS Blocking (Abis)

Analyze check channel availability rate (TCH Availability) & Transmission performance, any intermittent or not (Alarm). If all Ok then do the action coloum

check channel availability rate (TCH Availability) & Transmission performance, any intermittent or not (Alarm). If all Ok then do the action coloum

check channel availability rate (TCH Availability) & Transmission performance, any intermittent or not (Alarm). If all Ok then do the action coloum check channel availability rate (TCH Availability) & Transmission performance, any intermittent or not (Alarm). If all Ok then do the action coloum check channel availability rate (TCH Availability) & Transmission performance, any intermittent or not (Alarm). If all Ok then do the action coloum

Action 1.Reduce CRH (Cell Reselect Hysteresis = HYS) if site in the LAC border area and increase CRH for the NR cell in another LAC 2.Reduce CRO (Cell Resellect Offset =REO) or make negative value by set Penalty Time (PET) to 640s 3.Add fix SDCCCH channel 1. increase (btsSpLoadDepTchRateLower = FRL) & (btsSpLoadDepTchRateUpper=FRU) maximum value is 90 2. Increase (amrSegLoadDepTchRateLower = AFRL) & (amrSegLoadDepTchRateUpper = AFRU) 3. Change SDCCH &PDCH to TCH channel 4. Reduce hoMarginPbgt from blocking cell and increase hoMarginPbgt to NR cell that is no blocking 1. same as upper reduce SDCCH & TCH blocking 2. Change PDCH to TCH if PDCH not blocking or less 3.upgrade TRX 1.Add Dedicated GPRS Capactity (CDED) by increase the number 2. Add Default GPRS Capacity (CDEF) byt increase the number (Dynamic) 1. Reduce egprsInitMcsAckMode (MCA) & egprsInitMcsUnAckMode (MCU)


Blocking


CS Blocking & Non PS blocking

TCH Blocking & Non SDCCH blocking


PS Blocking -> due to no PDCH resource PS Blocking & Non CS blocking

PS Blocking -> due to PDT resource PS Blocking-> no Abis Timeslot is Available

CS Blocking & PS blocking

2G/3G reselection ( traffic share)

First step check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis problem) check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis problem) check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis problem) check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis problem) check channel availability rate & Abis transmission availiblity rate,any intermittent rise TT (cause maybe due to Abis problem)


Second step 1. 2. 3. 4. 4.

Reduce SDCCHCONGTH (70 --> 50/40) Increase CELLRESH (LAC border area) Change TCH_HLF timeslot to TCHSD timeslot Add fix SDCCH timeslot Reduce RACHBT (109 --> 106)

1. 2. 3. 4.

Reduce HRACCT1 and HRACTAMRACT1 Reduce GPDPDTCH Reduce GMANPRESPRM & EMANPRESPRM Increase SDCCHCONGTH (max: 100)

1. Same as upper reduce SDCCH & TCH blocking 2. Increase PWRRED to 2 3. Upgrade TRX

1. Increase GMANPRESPRM & EMANPRESPRM 2. Increase GPDPDTCH

Rebalancing PRPTPGID 1. Change GASTRABISTH to 60-70-40-50 2. Add SUBTSLB on A-bis 1.Upgrade TRX or Abis transmission capacity 2.If upgrade limit,change PDCH to TCH (CS high priority) 3.Load sharing to 3G, FDD Qmin (7-->6[max -14db]) & SSEARCHRAT (2-->0) 1.Inter-RAT Cell Reselection Enable(IRAT reseclection) 2.Qsearch C Initial(seach 3G in Idle mode) 3.Qsearch I(7=always seach 3G) 4.FDD Qmin (3G candidate cells EC/NO threshold) 5.FDD Qmin Offset(candidate cells EC/NO offset)

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Parameter Name

1

Huawei

3G

NBMULCACALGOSELSWITCH

2

Huawei

3G

PILOTPO, DLDPCHSF256PILOTBIT

3

Huawei

3G

MAPSWITCH_MAP_HSUPA_TTI_2MS_SWITCH

4

Huawei

3G

N300

5

Huawei

3G

BeHsupa2msTTIratethd

6

Huawei

3G

CSRABCacOptSwitch

7

Huawei

3G

PsInactTmrForPreFstDrm

8

Huawei

3G

CQIFbCk, CQIFbCkforSHO

9

Huawei

3G

ULTOTALEQUSERNUM

10

Huawei

3G

HSPDSCHCODENUM

11

Huawei

3G

DLHOCECODERESVSF

12

Huawei

3G

HoASUtmr

13

Huawei

3G

RLMAXDLPWR & RLMINDLPWR

14

Huawei

3G

SSEARCHRAT

15

Huawei

3G

EAGCHCODENUM

16

Huawei

3G

UlOlcTrigThd

17

Huawei

3G

SMPAGECTHD & SMPAGERTHD

18

Huawei

3G

TrigRatioforUlRTWP

19

Huawei

3G


20

Huawei

3G

ULHOCERESVSF& ULRRCCERESVSF

21

Huawei

3G

DLLDRTRIGTHD

22

Huawei

3G

RSCALLOCM

23

Huawei

3G

DLCONVAMRTHD

24

Huawei

3G

DLCONVNONAMRTHD

25

Huawei

3G

DLOTHERTHD

26

Huawei

3G

DLHOTHD

27

Huawei

3G

DLCELLTOTALTHD

28

Huawei

3G

DLLDRFIRSTACTION

29

Huawei

3G

DLLDRSECONDACTION

30

Huawei

3G

DLLDRTHIRDACTION

31

Huawei

3G

DLLDRFOURTHACTION

32

Huawei

3G

DLLDRFIFTHACTION

33

Huawei

3G

SLOTFORMAT

34

Huawei

3G

DLLDRRELTHD

35

Huawei

3G

MAXTARGETULLOADFACTOR

36 37

Huawei Huawei

3G 3G

HSPAPOWER SM

38

Huawei

2G

MAXPDCHRATE

39

Huawei

2G

PDCHUPLEV

40

Huawei

2G

PDCHDWNLEV

41

Huawei

2G

UPDYNCHNTRANLEV

42

Huawei

2G

DWNDYNCHNTRANLEV

43

Huawei

2G

PSServiceBusyThreshold

44

Huawei

2G

IDLESDTHRES

45

Huawei

2G

TCHBUSYTHRES

46

Huawei

2G

AMRTCHHPRIORALLOW

47

Huawei

2G

AMRTCHHPRIORLOAD

48 49

Siemens Siemens

2G 2G

SDCCHCONGTH HRACTT1, HRAMRHRACT1

50

Siemens

2G

GPDPDTCHA

51

Siemens

2G

GASTRABISTH

52

Siemens

2G

CHTYPE=SDCCH (from TCH)

53

Siemens

2G

CHTYPE=TCH (from SDCCH)

54

Siemens

2G

CHTYPE=CCCH (from TCH)

55 56 57 58 59 60 61 62 63 64

Siemens Nokia Nokia Nokia Nokia Nokia Nokia Nokia Nokia Nokia

2G 2G 2G 2G 2G 2G 2G 2G 2G 2G

INIMCSDL btsSpLoadDepTchRateLower (FRL) btsSpLoadDepTchRateUpper (FRU) amrSegLoadDepTchRateLower (AFRL) amrSegLoadDepTchRateUpper (AFRU) hoMarginPbgt dedicatedGPRSCapacity (CDED) defaultGPRSCapacity (CDEF) egprsInitMcsAckMode (MCA) egprsInitMcsUnAckMode (MCU)

Category

Purpose

Power Blocking

Disable uplink call admission control algorithm

Power Blocking

Reduce DL Power Congestion & Increase HS Throughput

CE Blocking

Disable 2ms TTI for HSUPA service

SPU Load

reduce Maximum number of retransmissions of the RRC CONNECTION REQUEST message.E.g from 3 to 1

RTWP

increase Threshold of selecting TTI 2ms for HSUPA

Overall 3G Radio Blocking

Enable loose CAC algorithm for CS RAB

SPU Load

increase CELL-PCH inactivity timer for UEs enabled with the Fast Dormancy feature

RTWP

Reduce Uu Load & improve RTWP to increase CS Traffic

Power Blocking

Increase ULTOTALEQUSERNUM (e.g from 160 to 180)

Code Blocking

Reduce HSPDSCHMINCODENUM (e.g from 5 to 4)

Code Blocking

Modify DLHOCECODERESVSF to lower SF (e.g from SF32 to SF 64)


Increase HoASUtmr

RTWP

Increase RLMAXDLPWR & RLMINDLPWR (eg: 0/-150 to 20/-130)


time being increase SSEARCHRAT >0

HSDPA Throughput

increase EAGCHCODENUM, E.g from 1 to 2

Power Blocking

increase UlOlcTrigThd to 100 (while still in ALGORITHM_OFF)

Paging

Increase SMS Threshold e.g from SMPAGECTHD=85,SMPAGERTHD=75 to SMPAGECTHD=95,SMPAGERTHD=85;

RTWP

Increase TrigRatiororUlRTWP e.g 75 to 90

Power Blocking

decrease RLPower : RLMAXDLPWR,RLMINDLPWR (eg. 50,-100 to 0,150 )

Code Blocking

Set lower SF on ULHOCERESVSF& ULRRCCERESVSF e.g SF16->SF32


set DLLDRTRIGTHD to lower value

HSDPA Throughput

Change NodeB Resource allocation mode to Power Code Balance

Power Blocking

Increase DL Power threshold for AMR

Power Blocking

Increase DL Power threshold for Non-AMR

Power Blocking

Increase DL Power threshold for Other

Power Blocking

Increase DL Power threshold for HO

Power Blocking

Increase DL Power Total threshold

Power/Code Blocking

Rearange LDR Sequence

Power/Code Blocking


Power/Code Blocking


Power/Code Blocking


Power/Code Blocking


FACH Congestion

Change FACH SlotFormat to expand FACH Bandwidth using Higher format ex : from D8 to D10


set DLLDRTRIGTHD to lower value

HSUPA Throughput

Increase UL Load Factor of HSUPA

HSDPA Throughput HSDPA Throughput

Increase HSDPA Power Change MACHSPARA SM to MAXCI

PDCH Blocking

Reduce PDCH blocking

PDCH Blocking

Reduce TBF congestion

PDCH Blocking


PDCH Blocking


PDCH Blocking


PDCH Blocking


SDCCH Blocking

Reduce SDCCH blocking

TCH Blocking

Reduce SDCCH & TCH blocking

TCH Blocking


TCH Blocking


SDCCH Blocking TCH Blocking

Reduce SDCCH Blocking Reduce TCH Blocking Increase/decrease dynamic PDCH allocation to reduce PDCH Blocking

PDCH Blocking Abis Blocking

Reduce A-bis pool blocking in order to improve PDASR

SDCCH Blocking

Reduce SDCCH Blocking with change Channel Type from TCH to SDCCH

SDCCH Blocking

Reduce TCH Blocking with change Channel Type from SDCCH to TCH

SDCCH Blocking PCU Load TCH Blocking TCH Blocking TCH Blocking TCH Blocking TCH Blocking PDCH Blocking PDCH Blocking PDCH Blocking PDCH Blocking

Resolve AGCH and PCH overload with change Channel Type from TCH to CCCH To reduce initial Coding Scheme Reduce TCH Blocking Reduce TCH Blocking Reduce TCH Blocking Reduce TCH Blocking Reduce TCH Blocking Reduce PDCH Blocking Reduce PDCH Blocking Reduce PDCH Blocking Reduce PDCH Blocking

Applicable Condition When Cell having Low accessibility due UL Power Congestion >0.5%

When Cell having Low accessibility due DL Power Congestion >0.5% When Cell having Low accessibility due UL Power Congestion >0.5%

High SPU Load due traffic increase >70%

UL CE Congestion, UL Power Congestion >0.5%

When Cell having Low accessibility due CS RAB Congestion >0.5%

High SPU Load due traffic increase >70%

Cell having high DCR CS with High RTWP indication

When Cell having Low accessibility due UL- Power Blocking for Existing value is less than 200

When Cell having Low accessibility due Code Blocking >0.5%

When Cell having Low accessibility due Code Blocking >0.5%

when many cells is having High Drop CS due to ASU/SRB Reset when cell is having High Drop CS due to RL/No Reply & Power Blocking is low (suggest on cell with high power Capacity & DL Power cong <0.5%) when many cells is having High Drop CS due to interference, DCR >1% When HSUPA Throughput is low, suitable to optimize adhoc site such as VIP site Cell with High UL Power Cong (>0.5%)after Algorithm_OFF . To implement many cell need consider Processor Load is low to Medium (<70%)

RNC High Paging deletion (VS.Paging.FC.Disc.Num.CPUS)

Cell with High RTWP and no congestion issue

When Cell having Low accessibility due High DL Power Cong >0.5% When Cell having Low accessibility due RRC.Rej.ULCE.Cong Cell with High DL Power Blocking .To implement many cell need consider Processor Load is low to Medium When HSDPA Throughput is low, suitable to optimize adhoc site such as VIP site When Cell having Low accessibility due High DL Power Cong >0.5% When Cell having Low accessibility due High DL Power Cong >0.5% When Cell having Low accessibility due High DL Power Cong >0.5% When Cell having Low accessibility due High DL Power Cong >0.5% When Cell having Low accessibility due High DL Power Cong >0.5% When Cell having Low accessibility due High DL Power Cong/Code Cong >0.5% When Cell having Low accessibility due High DL Power Cong/Code Cong >0.5% When Cell having Low accessibility due High DL Power Cong/Code Cong >0.5% When Cell having Low accessibility due High DL Power Cong/Code Cong >0.5% When Cell having Low accessibility due High DL Power Cong/Code Cong >0.5%

When Cell having High FACH Congestion

Cell with High DL Power Blocking .To implement many cell need consider Processor Load is low to Medium Low Throughput in Cell Level Low Throughput in Cell Level Low Throughput in Cell Level

PDCH blocking due to no Convertable TCHs PDCH blocking due to CELL PDCH Ratio Thresh

PDCH blocking due to CELL PDCH Ratio Thresh

PDCH blocking due to no Convertable TCHs




TCH blocking & SDCCH, TCH blocking

TCH blocking & SDCCH, TCH blocking

TCH blocking & SDCCH, TCH blocking SDCCH Utilization > 80% TCH Blocking Rate > 1% PDCH Blocking Rate > 1% Abis Pool Loss Rate > 0.5% SDCCH Blocking > 0.5% TCH Blocking > 1% AND SDCCH Utilization < 50% PCH load + AGCH load > 80% PCU Load > 90% and PDCH Blocking Rate > 1% TCH Blocking Rate > 1% TCH Blocking Rate > 1% TCH Blocking Rate > 1% TCH Blocking Rate > 1% TCH Blocking Rate > 1% PDCH Blocking Rate > 1% PDCH Blocking Rate > 1% PDCH Blocking Rate > 1% PDCH Blocking Rate > 1%

Cons Noise will increase without admission control Algorithm, might increase RTWP/degrade EcNo CS/PS CDR may increase on RNC has the poor coverage, or the coverage radius is big, use higher PILOTPO=8 on this condition HSUPA Throughput will degraded with only 10 ms TTI lower value UE experiences difficulty accessing the network when the Uu interface quality is poor or the system is overloaded user perceive will degraded with higher threshold to HO from 10ms to 2ms TTI PS service setup success rate and the cell capacity for PS services will decrease in the case of cell resource congestion PS Total Traffic will decrease & RRC SR will statistically degrade due less attempt

If value is larger, the cell capacity for uplink equivalent user number (ENU) is large and more users will be admitted HSDPA Throughput will degraded with lower PDSCH Code degrading bitrate might occur while HO or RRC SHO Overhead will be degraded DL Power Cong will increase Traffic aggresively to 2G higher value will waste downlink codes impact to processor load if too many cells implemented

increase CPU Load Might impact to capacity since UE QOS will trigger to TTI 2ms in case of overload Fail due Uu No reply/RL fail will increase degrading bitrate might occur while HO or RRC impact to processor load if too many cells implemented SET MACHSPARA:LOCELL=4,RSCALLOCM=POWERCODE_BAL ; Noise will increase, might increase RTWP Noise will increase, might increase RTWP Noise will increase, might increase RTWP Noise will increase, might increase RTWP Noise will increase, might increase RTWP

impact to processor load if too many cells implemented

Throughput Throughput

Throughput

Throughput

Throughput

Throughput

TCH utilization

quality

quality

quality Possible increase TCH Blocking Degraded voice quality and SQI Possible increase TCH Blocking Low throughput Possible increase TCH Blocking Possible increase SDCCH Blocking Possible increase TCH Blocking Low throughput Degraded voice quality and SQI Degraded voice quality and SQI Degraded voice quality and SQI Degraded voice quality and SQI Degraded voice quality and SQI Possible increase TCH Blocking Possible increase TCH Blocking Possible increase TCH Blocking Possible increase TCH Blocking

Command Sample (O

MOD UCELLALGOSWITCH:CELLID=xxxxx,NBMULCA

SET UFRC:PILOTPO=4,DLDPCHSF

SET UCORRMALGOSWITCH:MAPSWITCH=MA

SET UIDLEMODETIMER:

SET UFRC:BEHSUPA2MSTTIRAT

MOD UCELLALGOSWITCH:CELLID=XXXXX,

SET UPSINACTTIMER:PSINACTTMRFO

MOD UCELLHSDPCCH:CELLID=XXXXX,CQIFBC

MOD UCELLCAC:CELLID=XXXXX,ULTO

MOD UCELLHSDPA:CELLID=XXXXX,ALLOCCODEMO

MOD UCELLCAC:CELLID=31890,DLHO

SET USTATETIMER:HOASU

MOD UCELLRLPWR:RLMAXDLPWR=2

ADD UCELLSELRESEL:CELLID=XXX

ADD UCELLHSUPA:CELLID=31890,E

ADD UCELLLDM:CELLID=31890,UL

SET FCCPUTHD:BRDCLASS=XPU,SMPAGEC

MOD UCELLLDM:CELLID=XXXXX,TRIG

MOD UCELLRLPWR:RLMAXDLPWR=0

ADD UCELLCAC:CELLID=31890,ULH

ADD UCELLLDM:CELLID=31890,D

SET MACHSPARA:LOCELL=4,RSCALLO

MOD UCELLCAC: CELLID=1, DLC

MOD UCELLCAC: CELLID=1, DLCON

MOD UCELLCAC: CELLID=1, DL

MOD UCELLCAC: CELLID=1, D

MOD UCELLCAC: CELLID=1, DLC

MOD UCELLLDR: CELLID=1, DLLDRFI

MOD UCELLLDR: CELLID=1, DLLDRSECON

MOD UCELLLDR: CELLID=1, DLLDRTHI

MOD UCELLLDR: CELLID=1, DLLDRFOURTHACT

MOD UCELLLDR: CELLID=1, DLLDRFIFTHACTIO

DEA UCELL: CELLID= DEA USCCPCH: CELLID=3070

RMV UFACHLOCH: CELLID=307 RMV UFACHDYNTFS: CELLID=30706, TR RMV UFACHDYNTFS: CELLID=30706, TR RMV UFACH: CELLID=30706 RMV UFACH: CELLID=30706 RMV USCCPCH: CELLID=3070

ADD USCCPCHBASIC: CELLID=30706, PHYCHID=9, SCCPCHOFFSET=100, SC ADD USCCPCHTFC: CELLID=30706, ADD USCCPCHTFC: CELLID=30706, ADD USCCPCHTFC: CELLID=30706, ADD USCCPCHTFC: CELLID=30706, ADD USCCPCHTFC: CELLID=30706, ADD USCCPCHTFC: CELLID=30706, ADD USCCPCHTFC: CELLID=30706, ADD UFACH: CELLID=30706, PHYCHID=9, TRCHID=4, RATEMATCHINGATTR=220, TOAWS= ADD UFACH: CELLID=30706, PHYCHID=9, TRCHID=5, RATEMATCHINGATTR=130, TOAWS CHCODINGTYPE=TU ADD UFACHDYNTFS:CELLID=30706, TRCHID=4, RLCSIZE=168, TFSNUMB ADD UFACHDYNTFS:CELLID=30706, TRCHID=5, RLCSIZE=360, TFSNUMB ADD UFACHLOCH: CELLID=307 ACT USCCPCH: CELLID=3070 ACT UCELL: CELLID=3

ADD UCELLLDM:CELLID=31890,D

MOD UCELLHSUPA: CellId=1, MAXTARG

MOD UCELLHSDPA: CellId=1, SET MACHSPARA:LOCELL=1

SET GCELLPSCHM: IDTYPE=BYID, CELLID

SET GCELLPSCHM:IDTYPE=BYID,CELL

SET GCELLPSCHM:IDTYPE=BYID,CELLID

SET GCELLPSCHM:IDTYPE=BYID,CELLID=

SET GCELLPSCHM:IDTYPE=BYID,CELLID=1

SET GCELLPSCHM:IDTYPE=BYID,CELLID=1,PS

SET GCELLCHMGBASIC:IDTYPE=BYID,CE

SET GCELLCHMGAD:IDTYPE=BYID,CELL

SET GCELLCHMGAD:IDTYPE=BYID,CELLID=1,AMRTCHHPR

SET GCELLCHMGAD:IDTYPE=BYID,CELLID=1,AMRTCHHPR

Click to return to main page Equipment

Tech

Parameter Name

Category

Huawei

3G

BeHsupa2msTTIratethd

RTWP

Huawei

3G

CQIFbCk, CQIFbCkforSHO

RTWP

Huawei

3G


RTWP

Huawei

3G

TrigRatioforUlRTWP

RTWP

Purpose

Applicable Condition

increase Threshold of selecting TTI 2ms for HSUPA

UL CE Congestion, UL Power Congestion >0.5%

Reduce Uu Load & improve RTWP to increase CS Traffic

Cell having high DCR CS with High RTWP indication

Increase RLMAXDLPWR & RLMINDLPWR (eg: 0/-150 to 20/130)

when cell is having High Drop CS due to RL/No Reply & Power Blocking is low (suggest on cell with high power Capacity & DL Power cong <0.5%)

Increase TrigRatiororUlRTWP e.g 75 to 90

Cell with High RTWP and no congestion issue

Cons

Command Sample (Optional)

user perceive will degraded with higher threshold to HO from 10ms to 2ms TTI

SET UFRC:BEHSUPA2MSTTIRATETHS=D1024; MOD UCELLHSDPCCH:CELLID=XXXXX,CQIFBCK=D20,CQIFBCKFO RSHO=D20

DL Power Cong will increase

MOD UCELLRLPWR:RLMAXDLPWR=20, RLMINDLPWR=-130

Might impact to capacity since UE QOS will trigger to TTI 2ms in case of overload

MOD UCELLLDM:CELLID=XXXXX,TRIGRATIOFORULRTWP=73;

Click to return to main page Equipment

Tech

Parameter Name

Category

Huawei

3G

EAGCHCODENUM

HSDPA Throughput

Huawei

3G

RSCALLOCM

HSDPA Throughput

Huawei

3G

MAXTARGETULLOADFACTOR

HSUPA Throughput

Huawei

3G

HSPAPOWER

HSDPA Throughput

Huawei

3G

SM

HSDPA Throughput

Purpose

Applicable Condition

increase EAGCHCODENUM, E.g from 1 to 2

When HSUPA Throughput is low, suitable to optimize adhoc site such as VIP site

Change NodeB Resource allocation mode to Power Code Balance

When HSDPA Throughput is low, suitable to optimize adhoc site such as VIP site

Increase UL Load Factor of HSUPA

Low Throughput in Cell Level

Increase HSDPA Power


Change MACHSPARA SM to MAXCI


Cons

Command Sample (Optional)

higher value will waste downlink codes

ADD UCELLHSUPA:CELLID=31890,EAGCHCODENUM=2;

SET MACHSPARA:LOCELL=4,RSCALLOCM=POWE RCODE_BAL;

SET MACHSPARA:LOCELL=4,RSCALLOCM=POWERCODE_BAL; MOD UCELLHSUPA: CellId=1, MAXTARGETULLOADFACTOR=90; MOD UCELLHSDPA: CellId=1, HspaPower=0; SET MACHSPARA:LOCELL=1,SM=MAXCI;

RNO Analysis Mate V1

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