Subcarrier allocation in OFDMA with time varying channel and packet arrivals

Date

2009-12-01

Author

Toktas, Engin
Uysal-Biyikoglu, Elif
Yılmaz, Ali Özgür

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

203
views

0
downloads

This study considers the design of efficient low-complexity algorithms for dynamic allocation of subcarriers to users in a multiuser transmitter using Orthogonal Frequency Division. The effects upon throughput and delay performances of several canonical algorithms of varying the number of users, the number of subcarriers, and the statistical characteristics of incoming packets are investigated. Consequently, a subcarrier allocation algorithm with low computational complexity and satisfactory performance in almost all cases of interest is developed. The significance of channel v.s. queue state information with respect to various statistical properties of packet arrival processes is explored through extensive simulations. The results carry implications for the amount of channel estimation and feedback necessary. Finally, a new experimental method is proposed and applied for obtaining the stability regions of the algorithms in consideration.

Subject Keywords

Algorithm design and analysis , Feedback, Channel estimation, Computational modeling, Computational complexity, Delay effects, Throughput, Frequency conversion, Transmitters, Heuristic algorithms

URI

https://hdl.handle.net/11511/57840

DOI

https://doi.org/10.1109/ew.2009.5357997

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

Subcarrier allocation in ofdma systems with time varying channel and packet arrivals Toktaş, Engin; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2008) 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 sim...
Efficient Edge-Preserving Stereo Matching Cigla, Cevahir; Alatan, Abdullah Aydın (2011-11-13) A computationally efficient stereo matching algorithm is introduced providing high precision dense disparity maps via local aggregation approach. The proposed algorithm exploits a novel paradigm, namely separable successive weighted summation (SWS) among horizontal and vertical directions with constant operational complexity, providing effective connected 2D support regions based on local color similarities. The intensity adaptive aggregation enables crisp disparity maps which preserve object boundaries and...
Antenna Switch Optimizations Using Genetic Algorithms Accelerated With the Multilevel Fast Multipole Algorithm Onol, Can; Karaosmanoglu, Bariscan; Ergül, Özgür Salih (2015-07-24) We present antenna switch optimizations using an efficient mechanism based on genetic algorithms and the multi-level fast multipole algorithm (MLFMA). Genetic algorithms are used to determine switch states for desired radiation and input characteristics, while cost-function evaluations are performed efficiently via an MLFMA implementation with dynamic error control. MLFMA is integrated into the genetic algorithm by extracting common computations to be performed once per optimization. Iterative convergence r...
Asynchronous design of systolic array architectures in cmos İsmailoğlu, Ayşe Neslin; Aşkar, Murat; Department of Electrical and Electronics Engineering (2008) In this study, delay-insensitive asynchronous circuit design style has been adopted to systolic array architectures to exploit the benefits of both techniques for improved throughput. A delay-insensitivity verification analysis method employing symbolic delays is proposed for bit-level pipelined asynchronous circuits. The proposed verification method allows datadependent early output evaluation to co-exist with robust delay-insensitive circuit behavior in pipelined architectures such as systolic arrays. Reg...
Direction of arrival estimation algorithm with uniform linear and circular array Caylar, Selcuk; Leblebicioğlu, Mehmet Kemal; Dural, Guelbin (2007-01-01) In this paper mutual coupling effects on Modified Neural Multiple Source Tracking Algorithm (MN-MUST) has been studied. MN-MUST algorithm applied to the Uniform Circular Array (UCA) geometry for the first time. The validity of MN-MUST algorithm in the presence of mutual coupling has been proved for both Uniform Linear Array (ULA) and UCA. Simulation results of MN-MUST algorithm are provided for UCA for the first time. The presence of mutual coupling degraded the MN-MUST algorithm performed in the absence of...

Citation Formats

E. Toktas, E. Uysal-Biyikoglu, and A. Ö. Yılmaz, “Subcarrier allocation in OFDMA with time varying channel and packet arrivals,” 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57840.