A REDUCED COMPLEXITY AND AN EFFICIENT CHANNEL ESTIMATION FOR OFDM

Lokesh A. Panchal

Abstract: During the last few years, the progress in wireless communication is widely increasing to mitigate the ever increasing demand of higher data rates. OFDM (Orthogonal Frequency Division Multiplexing) techniques using more densely packed carriers, thus achieving higher data rates using similar channels. In this paper, the estimation is based on the minimum mean square error (MMSE) estimator and the least square (LS) estimator. I derive the MMSE and LS estimators architecture and investigate their performances. I proved that the MMSE estimator performance is better but computational complexity is high, contrary the LS estimator has low complexity but poor performance. For reducing complexity I proposed two different solutions which are the Latest Least Square (LLS) estimator and the modified MMSE estimator. I evaluate estimator’s performance on basis of mean square error and symbol error rate for modulation systems.

Keywords: OFDM, LS, MMSE, LLS and Modified MMSE, SNR

DOI: https://doi.org/10.15623/ijret.2014.0306049