Subcarrier allocation in ofdma systems with time varying channel and packet arrivals

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2008

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Toktaş, Engin

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This study considers the average system throughput and the average delay performances of subcarrier allocation algorithms in OFDMA systems. The effects of varying the number of users, the number of subcarriers, and the statistical characteristics of incoming packets are investigated on the throughput and delay performances of the algorithms. Moreover, a new subcarrier allocation algorithm with low-order computational complexity, which performs very well almost all cases, is proposed. With the aid of the simulations, the significance of channel v.s. queue state information varying with the statistical characteristic of incoming packets is examined and reached some results which can be very valuable for channel estimation and feedback systems. Finally, the stability issue is considered in OFDMA systems and a new heuristic simulation-based method for obtaining the stability region of an OFDMA subcarrier allocation algorithm is proposed.

Subject Keywords

Electrical engineering., OFDMA.

URI

http://etd.lib.metu.edu.tr/upload/3/12610029/index.pdf
https://hdl.handle.net/11511/17970

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Toktaş, “Subcarrier allocation in ofdma systems with time varying channel and packet arrivals,” M.S. - Master of Science, Middle East Technical University, 2008.