Multichannel Communication based on Adaptive Equalization in Very Shallow Water Acoustic Channels

Abstract

Very shallow water acoustic communication channels are known to exhibit fading due to time-varying multipath arrivals. This is further complicated by impulsive snapping shrimp noise that is commonly present in warm shallow waters. This paper will present a communication channel model simulation for such a channel. The paper also presents results from the use of single-carrier differential phase shift keying (DPSK) modulation which does not require an elaborate method for estimating the carrier phase. The receiver designs in simulation and trial data analysis are based on the least mean square (LMS) adaptive linear equalizer (LE) and decision feedback equalizer (DFE). Multichannel combining and forward error correction (FEC) schemes such as turbo product codes (TPC) are employed to improve performance. We will present performance results based on simulated data as well as for real data collected from the sea. Copyright © (2006) by the Australian Acoustical Society.