microwave-basics

Marconi Academy

MDRS MD RS15 155E 5E – Op Oper erat atio ion n Modul Module e 1 - Introd Introduct uctio ion  n 

Microwave Radio Technology

STM-1

STM-1 ♦ ♦ ♦ ♦

STM-1 2 Mbit/s

Free-space propagation of electromagnetic waves Line of sight connection Frequency range • 3 to 38 GHz Short-haul and long-haul systems STM-1 2 Mbit/s

Microwave Radio Technology

Waveguide Long-haul system Short-haul system ♦ Range ♦ Range • 15 to 40 km • up to approx. 20 km (w/o diversity) ♦ Frequency range >80 km km • 40 - >80 • 15 to 38 GHz (with diversity) ♦ Transmission capacity ♦ Frequency range • 2 to 622 Mbit/s • 3 to 13 GHz ♦ Transmission capacity • 2 to 622 Mbit/s

Outdoor Unit

Coaxial cable

Microwave Micro wave Radio Techn Technology ology - System Design Designation ations s

Long-haul systems 155/7500 500 - 64 QAM QAM ♦ MDRS 155/7 microwave radio radio - 7R design design • SDH microwave 155/6800 800 - 64 MLQAM MLQAM E ♦ MDRS 155/6 155/13000 - 128 MLQAM E ♦ MDRS 155/13000 microwave radio radio - ETSI design design • SDH microwave • Short name: MDRS 155 E ♦ MDRS 2-34/ 2-34/7400 7400 - 16 QAM QAM 2x34/7400 7400 - 64 QAM QAM ♦ MDRS 2x34/ microwave radio radio - 7R design design • PDH microwave

Short-haul systems 155/1870 8700 0 - 16 QAM QAM N ♦ MDRS 155/1 microwave radio radio - "NKRS" • SDH microwave • Short name: MDRS 155 N 155/2300 3000 0 - 16 MLQAM MLQAM C ♦ MDRS 155/2 microwave radio - "Compact" "Compact" • SDH microwave • Short name: MDRS 155 C ♦ MDRS 155/2600 155/26000 0 - 128 MLQAM S • SDH microwave radio • Short name: MDRS 155 S

Classical Design Waveguide

Waveguide

RF f [GHz]

Circulator, Filter (CBN)

Circulator, Filter (CBN)

RF = Radio Radio freque frequency ncy e.g. 7.5 GHz, 18.7 GHz

TX

RX

Transmitter

Receiver

IF = Intermediate frequency e.g. 140 MHz Modulator 16 - 128 128 QAM QAM

Demodulator 16 - 128 QAM

BB = Baseband e.g. 155 Mbit/s Channel

Channel

Classical Design MD TX

CBN

f1

f2

CBN

f3

Tx side

Rx side

Chan Ch anne nell 3

MD

TX

Chan Ch anne nell 2

MD

TX

Chan Ch anne nell 1

MD

TX

f3

RX

DM

Chan Ch anne nell 1

f2

RX

DM

Chan Ch anne nell 2

f1

RX

DM

Chan Ch anne nell 3

TX

MD

f1

Chan Ch anne nell 3

RX DM

DM

f2

f3

RX

Chan Ch anne nell 1

Tx side

Rx side Band filter

Circulator

Absorber

Microw Mic rowave ave Radio Radio Technolog Technology y - Fre Frequen quency cy Patter Patterns ns f1a f1b f1 f1a

f1a

MD

f1’ f1b

f1b

TX

TX

MD

RX

RX

DM

f1b

f1a

CBN

DM

CBN

Duplex spacing Channel Channel spacing width

f1 f1a

f2 f2a

f3 f3a

f4 f4a

f1` f1b

Lower band

f2` f2b

f3` f3b

Upper band Allocated frequency range

f4` f4b

Frequency Frequen cy Patterns Patterns - Transm Transmission ission via 2 Pola Polarizatio rizations ns Orthomode transducer (OMT)

V: vertical

1st polarization

90°

f1a

MD

TX

f1 CBN

DM

H horizontal

RX f1b

ACDP: Adjacent Channel Dual Polarisation

2nd polarization

H horizontal

f1a

MD

TX

f1

f3 f3a f2 f2a

V vertical

CBN

DM

f1 f1a

f5 f5a f4 f4a

f6 f6a

RX f1b

H horizontal

H

V

V vertical

CCDP: CoCo- Channel Dual Polarisation Polarisation

f1 f1a f1 f1a

f2 f2a f2 f2a

f3 f3a f3 f3a

f4 f4a f4 f4a

Bandwidth/Channel Width Channel/bandwidths ♦

16 QAM

♦

Transmission

the smaller the channel/  bandwidth (advantage) ♦ the more sensitive to interference (disadvantage)

•

SDH • 155 Mbit/s ♦

16 QAM •

< 45 MHz • MDR MDRS S 155/.. 155/....- 16 MLQAM MLQAM ♦

64 QAM

64 QAM < 30 MHz • MDR MDRS S 155/.. 155/....- 64 MLQAM MLQAM •

♦

The higher the modulation stage

1024QAM 512QAM 256QAM

128 QAM < 26 MHz • MDR MDRS S 155/.. 155/....- 128 MLQAM MLQAM •

128QAM 128 QAM

Channel width f1 f1a

f2 f2a

f3 f3a

64QAM 16QAM

f4 f4a

     y       t       i      v       i       t       i      s      n      e       S

4PSK Channel width

Freque Fre quency ncy Pat Patte terns rns - Chan Channel nel Spac Spacings ings ITU-R F.382 6 Ch. 29 MHz 382 3824.5 4.5 - 418 4182.5 2.5 MHz MHz ITU-R F.382 6 Ch. 29 MHz 341 3413.0 3.0 - 377 3771.0 1.0 MHz MHz ITU-R F.497 8 Ch. 28 MHz 342 3422.5 2.5 - 388 3884.5 4.5 MHz MHz ITU-R F.635 7 Ch. 40 MHz 362 3620 0 - 418 4180 0 MHz MHz ITU-R F.635* 7 Ch. 40 MHz 361 3610 0 - 417 4170 0 MHz MHz ITU-R F.635 4 Ch . 80 MHz 363 3630 0 - 419 4190 0 MHz MHz ITU-R F.1099 7 Ch. 40 MHz 443 4430 0 - 497 4970 0 MHz MHz ITU-R F.1099 4 Ch. 80 MHz 445 4450 0 - 499 4990 0 MHz MHz

3

5

4

6

7

8

9

10

4 (3.6/3.8/3.9 GHz) 5 (4.7 GHz)

ITU-R F.383 8 Ch. 29.65 MHz 5945.20 5945.20 - 640 6404.79 4.79 MHz ITU-R F.497 8 Ch. 28 MHz 5689 5689 - 615 6151 1 MHz MHz

6L (6.2 GHz)

ITU-R F.384 8 Ch. 40 MHz 6460 6460 - 708 7080 0 MHz MHz

6U (6.8 GHz)

ITU-R F.385 5 Ch. 28 MHz 744 7442 2 - 770 7708 8 MHz MHz ITU-R F.385* 5 Ch. 28 MHz 742 7428 8 - 772 7722 2 MHz MHz ITU-R F.385 5 Ch. 28 MHz 712 7121 1 - 742 7429 9 MHz MHz ITU-R F.385 5 Ch. 28 MHz 745 7457 7 - 773 7737 7 MHz MHz ITU-R F.385 8 Ch. 28 MHz 744 7442 2 - 788 7883 3 MHz MHz

ITU-R F.386 8 Ch. 29.65 MHz 7747.70 7747.70 - 826 8266.57 6.57 MHz ITU-R F.386 3 Ch. 28 MHz 8293 8293 - 846 8468 8 MHz MHz ITU-R F.387 ITU-R F.387 ITU-R F.387

40 MHz 107 10715 15 - 116 11685 85 MHz MHz 10695 95 - 116 11665 65 MHz MHz 40 MHz 106 12 Ch. 40 MHz 107 10735 35 - 116 11665 65 MHz MHz 12 Ch.

7 (7.5 GHz)

Channel spacing

8 (8 GHz) 11 (11 GHz)

12 Ch.

ITU-R F.387 8 Ch. 28 MHz 12765 12765 - 132 13227 27 MHz MHz

11

f3 f3a

f4 f4a

13 (13 GHz)

12

13

Exploitation of Frequency Patterns 40 MHz frequency pattern (e.g. 6.8 GHz) f1

f2

f3

f4

f1

f2

f3

f4

64 QAM

Channel spacing 40 MHz

Channel width 30 MHz

f1

f2

f3

f4

f1

f2

f3

f4

28 MHz frequency pattern (e.g. 7.5 GHz or 13 GHz) f1

f3 f2

128 QAM

64 QAM

f5 f4

f6 30 MHz Channel width

Channel spacing 28 MHz

f1

f2

f3

f4

f5

f6

f1

f2

f3

f4

f5

f6

128 QAM

26 MHz Channel width

Additional Attenuation 100

Rain 150mm/h

10 Rain 25mm/h

dB/km 1 Rain 16mm/h

Attenuation due to precipitation ... ♦

depends on the intensity ♦ depends on the radio hop length ♦ depends on the frequency

mm/h (millimeters (millimeters per hour)

0.1

0.01

1

2

5

10

20

50 1 00

Addit Add ition ional al Att Attenu enuat atio ion n - Mu Mult ltip ipath ath Pr Propa opaga gati tion on Half-power beamwidth, e.g. ...°

e.g. 50 km

approx. .... m

218 m λ

λ

= wavelength

Case 1

+

=

Case 2

+

=

Case 3

+

=

Microw Mic rowave ave Radio Radio Technol Technology ogy - Spac Space e Diversi Diversity ty ∆

∆

MD STM-1

DM +

TX RX RX

CBN Main CBN Div

CBN Main CBN Div

TX RX RX

MD STM-1

+ DM Length compensation

Maximum Radio Hop Lengths AntennaeDiameter

MDRS 155/3900-64 MLQAM With Space Diversity

1.2 m

MDRS 155/4700-64 MLQAM

2m

With Space Diversity

3m

MDRS 155/6200-64 MLQAM With Space Diversity MDRS 155/6800-64 MLQAM With Space Diversity MDRS 155/7500-64 MLQAM With Space Diversity MDRS 155/8000-64 MLQAM With Space Diversity MDRS 155/13000-64 MLQAM With Space Diversity

0

10

20

30

40

50

60

70

Hop Length / km Space Diversity Climate: Central Europe; BER=2x10E-5; Feeder: 2x30m; w/o Interference; Pout: 0.001%; rain is not considered

80

90

100

Microwave Micro wave Radio Techn Technology ology - Frequ Frequency ency Divers Diversity ity f f1

f3

f3a

MD T X MD T X Chan Ch anne nell 1

RPS

f3b

f1a

DM RX DM RX f1b

CBN

f1 f1a

f3 f3a

f1’ f1b

f3’ f3b

Microw Mic rowave ave Radio Radio Tech Technolo nology gy - Fre Fresne snell Zone Zone Distance d b

Radius b

1st Fresnel zone:d +1⋅

λ

2

Microwave Micro wave Radio Techn Technology ology - System Design Designation ation 3+1

N Betrie Betriebska bskanal nal (BK) Operation Channel (OP) STM-1 STM-1 STM-1

MD DM MD DM MD DM MD DM

TX RX TX RX TX RX TX RX

MD DM MD OP1 DM MD OP2 DM MD OP3 DM

TX RX TX RX TX RX TX RX

OP1 OP2

RPS OP3 PR

PR

STM-1 STM-1 STM-1

RPS

C B N

C B N C B N

M Ersat Ersatzka zkana nall (EK) (EK) Protection Channel (PR)

H horizontal

OP1

PR

OP1

OP2

PR

OP3

V vertical

H horizontal V vertical

OP2

OP3

Syste Sy stem m Des Design ignat atio ion n - 3+ 3+1 1 Con Config figur urat atio ion n Ex Examp ample le OP1

OP1

MD

TX

RX

DM

OP2

MD

TX

RX

DM OP2

STM-1

OP3

MD

TX

RX

DM OP3

STM-1

PR1

MD

TX

RX

DM PR1

DM

RX

TX

MD

STM-1

OP2 DM

RX

TX

MD

OP2

STM-1

OP3 DM

RX

TX

MD

OP3

PR1 DM

RX

TX

MD

PR1

STM-1 STM-1 STM-1

Occas. traffic (OT)

STM-1

Occas. traffic (OT) (OT)

OP1

C B N

C B N

OP1

STM-1

Occas. traffic (OT) STM-1 STM-1 STM-1

Occas. traffic (OT)

1+0 Equipm Equipment ent Protect Protection ion - "1+1 HSB" Configura Configuration tion f1 f1a

f1` f1b

Station A

Ch. 1 (STM-1) RPS

Station B

PR

f1a

f1a

PR

MD

TX

RX

DM

MD

TX

RX

DM

OP

f1a

f1a

OP

C B N

C B N

10dB

f1b

PR

DM RX

TX

MD

DM RX

TX

MD

f1b

OP

PR

OP

f1b

f1b

10dB

RPS

Ch. 1 (STM-1)

1+0 1+ 0 Equ Equip ipmen mentt Pro Prote tect ctio ion n - Spa Space ce Div Diver ersi sity ty f1 f1a

f1` f1b

Station A

Ch. 1 (STM-1) RPS

Station B

PR

f1a

MD

TX

MD

TX

OP

f1a

PR

CBN

C B N

f1b

DM RX DM RX OP

f1b

CBN

C B N

f1a

PR

RX

DM

RX

DM

f1a

OP

f1b

PR

TX

MD

TX

MD

f1b

OP

RPS

Ch. 1 (STM-1)

Block Bloc k Diagra Diagram m - 2+0 Conf Configur iguratio ation n with with XPIC horizontal f1a MD TX Ch. 1 (STM-1)

140 MHz

DM

H CBN

RX

V

f1b

f1b horizontal

f1 OP1

TX

f

RX

f1b 2 Waveguide pro Station

TX

140 MHz

DM

PW

f1a Ch. 2 (STM-1)

Ch. 1 (STM-1)

f1a

PW

MD

140 MHz

CBN

OP2 f1

MD

TX

CBN

140 MHz

CBN

DM RX vertical f1b

RX f1a

H

V

H

V

MD Ch. 2 (STM-1)

DM vertical

Clock synchronization Data compensation

Terms Term s of Microwav Microwave e Radio Radio Technolo Technology gy - XPIC Principl Principle e

H MD TX

H + x•V

H

CBN CB

CBN RX

ATDE

+

ATDE

+

H

-x•H x•V

PW MD TX

-x•V

PW

x•H

CBN CB

CBN RX

V

V

V + x•H

H

H

f

V

ATDE

XPD

f

V

XPIC

V

Terms Ter ms of Microwa Microwave ve Radio Radio Technolo Technology gy - Ide Identif ntifiers iers f1b 0010 0001

f1a

f1a

f1a 0011

f1b

f1b

f1a f1b

0100

Interferences ♦

Reason: Interferences on the same channel

Radio hop identifier ♦

prevents the transmission of a co-channel interferer (e.g due to overlengths)

Terms Term s of Microwave Microwave Radio Radio Technolo Technology gy - System Overvi Overview ew CBN waveguide

TX

CBN waveguide

Output power

Max. power e.g. +31 dBm [1.25 W]

RX

Input power

System attenuation (e.g. 71.7 dB) Antenna CBN gain waveguide e.g. e.g. 41.4 dB 5.3 dB

Free space space attenuation attenuation e.g. 143.9 dB (Distance d = 50 km) (Frequency: f = 7.5 GHz)

Antenna CBN gain waveguide e.g. e.g. 41.4 dB 5.3 dB

System gain

Fading margin a = 92.4 + 20 ⋅ log(d[km] ⋅ f[GHz]) 0

min. power e.g. -73 dBm [50 pW]

Bit Error Ratio (BER) 1E-4 BER Radio hop interference

1E-5

1E-6 1E-7 BER measuring unit

BER =

Measured errors [bits]  bits  Data rate  ⋅Time [s]   s 

Example: BER =

1E-8 1E-9 1E-10 1E-11

1E-12 100 bits =1.072 ⋅10−8 Mbits ⋅1min 155.52 s

-75

-70

-65 PRX [dBm] at A

Transmission Performance Transmission performance performance of radio hops Availability

Performance

Unavailable time BER > 1E-3 (t > 10 s) > 30% errored blocks (t > 10 s)

Radio hop

ITU-T G821 ITU-T G826

Failures caused by various factors

Available time 0 < BER < 1E-3 < 30% errored blocks

Errored Errored seconds seconds ES 0 < BER < 1E-3 < 30% errored blocks Severely errored seco second nds s SES SES BER > 1E-3 (t < 10s) > 30% errored blocks blocks (t<10 (t<10s) s)

Degraded minu minute tes s DM 1E-6 < BER < 1E-3

Error-free seconds EFS BER = 0 0% errored blocks

Transmission Performance BER 1E-1 (0.1) BER 1E-2 (0.01) BER 1E-3 (0.001) BER 1E-4 (0.0001) BER 1E-5 (0.00001) BER 1E-6 (0.000001) BER 1E-7 BER 1E-8 BER 1E-9 BER 1E-10 BER 1E-11 t [s]

•

ES - (Errored Seconds) • SES - (Severely Errored Seconds) • UT - (Unavailable Time) (SDH: (SDH: UAS - Una Unavaila vailable ble Seconds Seconds))

Terms Ter ms of Microwav Microwave e Radio Radio Technolog Technology y - Int Interf erface aces s T´ - Input Bas Base eband Z´ - Outp Output ut Modu Modula lato torr (ZF (ZF)) A´ - Outpu utputt Tran Transm smit itte terr B´ - Outp Output ut RF Filt Filter er (TX) (TX) C´ - Outp Output ut Ci Circ rcul ulat ator or (TX) (TX) D´ - Inp Input OMT (TX (TX) D - Outp Output ut OMT OMT (RX) (RX) C - Input Input Circu Circulato latorr (RX) (RX) B - Input Input RF RF Filte Filterr (RX) (RX) A - Inpu Inputt Rece Receiv iver er Z - Input Input Demo Demodu dulato latorr (ZF) (ZF) T - Outp Output ut Bas Baseb eband and

Z´

T´

MD

A´

PW

D´

B´

TX

Tx side C´

PW

D

B

A

Z

RX

T

DM

C

Rx side

Baseband Code CMI code

HDB-3 code

♦

CMI - Code Coded d Mark Mark Inversio Inversion n ♦ Free from DC due to alternating polarity ♦ Used for bit rates > 140Mbit/s •

Binary value: log. 0 − first clock half always negative − second edge always positive − always positive rising edge • Binary value: log. 1 − entire clock period alternating with positive and negative potential

♦

Modified AMI code ♦ Transmission code for 2, 8 and 34 3 4 Mbit/s • Additional bit V prevents sequences of more than three log. 0s. • Additional bit has same polarity as last data bit. • If no or an even number of log. 1s follows two violation bits, an AMI additional pulse is inserted three bits before the next violation bit.

Clock

Clock

Data

Data CMI

1

1

1

0

0

1

0

1

0

1

1 1 0 0 0 0 1 1 0 0 0

0 0 0

0 0

A 0 0 V A 0

0 V

0 HDB3 1

1

0 0

0

V 1 1