An adaptive linear multiuser receiver for deep water acoustic local area networks

The acoustic local area network (ALAN) is designed for multipoint-to-point telemetry between ocean bottom sensors and a surface receiver in deep water areas. The main obstacle for coherent communications in this channel is strong multiple-access interference from cochannel signals, which affects a common narrowband request channel. Throughput and packet delay in this network depends on the capability of the receiver to resolve collisions between request packets. In this paper we propose an adaptive multiuser receiver for joint parameter estimation and multiple-access interference cancellation. It extends previous work on adaptive multiuser detectors to the more realistic communication scenario by estimating signal parameters rather than assuming that they are known. The adaptive approach is different from the one used in a centralized multiuser receiver in that no knowledge of the signature sequences of any of the active users is required