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SENIOR YEAR THESIS SYNOPSIS:
PROJECT SUMMARY:
The hardware implementation of smart antenna system consists of Uniform Linear Array (ULA) with half-wavelength interval each, multi-channel calibrated transceiver, AD/DA converters and Field Programmable Gate Array (FPGA) based digital processing unit together with optimum Direction of Arrival (DoA) estimation and beam forming algorithms. Here we concentrate our efforts on developing a ULA system for the smart antenna system so as to enable it for fixed WiMAX base stations. The array system is to be designed and optimized to a frequency of 2.5 GHz, according to the IEEE 802.16a specifications using IE3D EM Modeling software. After the array has been optimized, the Direction of Arrival and beam forming algorithms are implemented.
NEED FOR THE PROPOSAL:
Campus systems require high data capacity, low latency, a large coverage footprint, and high security: Like other usage scenarios, campus networks carry a mix of voice, data, and video, which the WiMAX QoS helps prioritize and optimize. It takes less time and resources to interconnect a campus through a WiMAX network, since excavation and external construction are not required. Also the lead-time to deploy a wired solution is much longer than the lead-time to deploy a WiMAX solution, without offering any accompanying benefits. Thus WiMAX provides an ideal networking solution for such a scenario. WiMAX currently uses the standard omni-directional antenna system in which the beam is spread in all directions. This causes unnecessary power losses, limited frequency reuse and reduced spectral efficiency. These drawbacks are overcome by the emergence of a new technology “Smart Antennas”. Smart antennas automatically change the directionality radiation patterns in response to its signal environment. This endows it with better range and coverage, multipath rejection, increased capacity and reduced deployment costs. Thus we find a significant need to combine the advantages of both WiMAX and smart antennas to create an ideal networking environment.
ORIGIN:
Wired Broadband Internet and services are widespread in the present age. The biggest disadvantage of this is the confusion caused by the large amount of wires and lack of mobility. Wi-Fi (IEEE 802.11) has freed us to move around our office and many public places with our laptops and handhelds. However, Wi-Fi has its own drawbacks. Since the available unlicensed frequency for transmitting communications is limited and the lack of cooperation between various transmitting schemes increases the number of mid-air collisions. Moreover, Wi-Fi is a short range service (30 meter coverage).To overcome these difficulties, a new standard is incorporated. WiMAX, which stands for Worldwide Interoperability for Microwave Access is the popular name of the IEEE 802.16a wireless metropolitan-area network standard. WiMAX can span distances of up to 31
miles, non line of sight. Each base station can transmit up to 280 Mbps with individual signals ranging up to 70 Mbps. WiMAX uses low frequencies, in the 2 to 11 GHz range with a bandwidth of 1.25 to 20 MHz. Since the early days of wireless communications, there has been the simple dipole antenna, which radiates and receives equally well in all directions. To find its users, this single-element design broadcasts omni directionally. While adequate for simple RF environments where no specific knowledge of the users' whereabouts is available, this unfocused approach scatters signals, reaching desired users with only a small percentage of the overall energy sent out into the environment. Collocated with a base station, a smart antenna system combines an antenna array with a digital signalprocessing capability to transmit and receive in an adaptive, spatially sensitive manner. They have an ability to distinguish between signals and interferers by directing beams in the directions of the desired signals and in the directions of interferers. Smart antenna systems could steer beams for reception in the direction of desired incoming signals OBJECTIVE:
To design and optimize a Uniform Linear Array (ULA) for a smart antenna system to be implemented in fixed WiMAX base stations.
NATIONAL AND INTERNATIONAL IMPORTANCE:
WiMAX implemented through smart antennas results in a powerful wireless networking system that can be used in areas such as mobile defense systems, rural connectivity, public safety, search and rescue scenarios and offshore communications.
SPECIFIC APPLICATIONS:
WiMAX-based education networks, using QoS, can deliver the full range of communication requirements, including telephony voice, operating data (such as student records), email, Internet and intranet access (data), and distance education (video) within the University.
TOOLS REQUIRED:
Matlab 7.0, IE3D, EMPIRE
MAIN REFERENCE:
Design and Optimization of an Antenna Array for WIMAX Base Stations W. Mahler, F.M. Landstorfer University of Stuttgart, Institute of Radio Frequency Technology, Germany
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