AUTHORS: Harjeet Singh, Savina Bansal

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ABSTRACT: Channel estimation is a crucial design issue for faithful reception of high data rate mobile applications in a wireless communication system. Channel estimation algorithms, mainly available in literature, include least square (LS) estimation, linear minimum mean squared error (LMMSE) estimation, and low rank linear minimum mean squared error (LRMMSE) estimation with varying degrees of performance. MMSE-based algorithms offer higher accuracy though at the cost of complexity in comparison to the low complexity LS algorithm. In this work, we propose an algorithm based on the LS channel estimation technique by using decision based feedback technique to improve upon its estimation capabilities and still retaining its simplicity. To examine its usefulness especially for wireless mobile applications, performance in terms of the symbol error rate is analyzed with varying Doppler frequency and delay parameters, which is found to be quite optimistic in comparison to LMMSE and LRMMSE algorithms.

KEYWORDS: Pilots symbols, Symbol error rate, Doppler frequency shift, OFDM

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