A Modified LS Channel Estimation Algorithm for OFDM System in Mountain Wireless Environment

Abstract Orthogonal frequency division multiplexing (OFDM) is a transmission technique that is based on many orthogonal carriers that are transmitted simultaneously. OFDM effectively mitigates inter symbol interference (ISI) and has high-efficient frequency utilization. OFDM channel estimation is one of the key technologies in the OFDM system. In this paper, channel estimation techniques for OFDM systems, based on pilot-aided channel estimation algorithm, over mountain wireless environment are investigated. It is well known that least square (LS) and linear minimum mean square error (LMMSE) algorithms are effectual channel estimation methods for OFDM. We propose a novel modified LS channel estimation method, which is based on noise reduction procedure to improve the channel estimation accuracy. The simulation results demonstrate that comparing to LS channel estimation algorithm, LMMSE algorithm and the proposed modified LS algorithm provide better performances.

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