Faculty Advisor or Committee Member

Alexander M. Wyglinski, Advisor

Faculty Advisor or Committee Member

Kaveh Pahlavan, Committee Member

Faculty Advisor or Committee Member

Sudharman K. Jayaweera, Committee Member

Identifier

etd-102309-152900

Abstract

"We proposed a novel spectrum allocation approach for distributed cognitive radio networks. Cognitive radio systems are capable of sensing the prevailing environmental conditions and automatically adapting its operating parameters in order to enhance system and network performance. Using this technology, our proposed approach optimizes each individual wireless device and its single-hop communication links using the partial operating parameter and environmental information from adjacent devices within the wireless network. Assuming stationary wireless nodes, all wireless communication links employ non-contiguous orthogonal frequency division multiplexing (NC-OFDM) in order to enable dynamic spectrum access (DSA). The proposed approach will attempt to simultaneously minimize the bit error rate, minimize out-of-band (OOB) interference, and maximize overall throughput using a multi-objective fitness function. Without loss in generality, genetic algorithms are employed to perform the actual optimization. Two generic optimization approaches, subcarrier-wise approach and block-wise approach, were proposed to access spectrum. We also proposed and analyzed several approaches implemented via genetic algorithms (GA), such as quantizing variables, using adaptive variable ranges, and Multi-Objective Genetic Algorithms, for increasing the speed and improving the results of combined spectrum utilization/cross-layer optimization approaches proposed, together with several assisting processes and modifications devised to make the optimization to improve efficiency and execution time."

Publisher

Worcester Polytechnic Institute

Degree Name

ME

Department

Electrical & Computer Engineering

Project Type

Thesis

Date Accepted

2009-10-23

Accessibility

Unrestricted

Subjects

Dynamic Spectrum Access, Distributed Wireless Networks, Cognitive Radio

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