Title | Adaptive symbol tracking using discrete stochastic approximation for wireless OFDM systems |
Publication Type | Conference Paper |
Year of Publication | 2004 |
Authors | Athaudage, C. R. N., and V. Krishnamurthy |
Conference Name | Communications, 2004 IEEE International Conference on |
Pagination | 2457 - 2463 Vol.4 |
Date Published | jun. |
Keywords | adaptive symbol tracking, approximation theory, brute force maximum-likelihood methods, computational complexity, discrete stochastic approximation, fading channels, frequency offsets, maximum likelihood estimation, OFDM modulation, orthogonal frequency division multiplexing, radio networks, self-learning capability, stochastic processes, synchronisation, time selective fading channels, time synchronization, time varying time delays, time-varying channels, wireless OFDM systems |
Abstract | This paper presents discrete stochastic approximation (DSA) algorithms for time synchronization in OFDM systems. It is shown that the discrete stochastic approximation algorithms can be effectively used to achieve a significant reduction in computational complexity compared to brute force maximum-likelihood (ML) methods for OFDM synchronization. The most important property of the proposed algorithms is their recursive self-learning capability - most of the computational effort is spent at the global or a local optimizer of the objective function. An adaptive version of the discrete stochastic approximation algorithm is also presented for tracking time varying time delays and frequency offsets in time selective fading channels. Detailed numerical examples illustrate the performance gains of these DSA based synchronization algorithms. |
URL | http://dx.doi.org/10.1109/ICC.2004.1312960 |
DOI | 10.1109/ICC.2004.1312960 |