SNR Estimation Algorithm Based on Pilot Symbols for DFT-Spread OFDM Systems over Underwater Acoustic Channels

Abstract

Abstract Effective and low complexity methods for signal to noise ratio (SNR) estimation remain a challenge to underwater acoustic communication due to the ocean environment characteristic which can be summarized as simultaneously severe frequency selectivity and fast-time variability. In this study, a novel SNR estimation method was proposed by using only one training symbols in the pilots and applied to DFT-Spread OFDM transmission system over underwater acoustic channels. The method will be effective against frequency selectivity and fast time varying of underwater acoustic channels. Simulations showed technically feasibility of our proposal. Further, a systematic investigation in the shallow water near Xiamen demonstrated that single training symbol based SNR estimator would be applicable for DFT-Spread OFDM system over underwater acoustic channels.