Analysis of the performance of an underwater acoustic communications system and comparison with a stochastic model

This paper describes the testing of an experimental 50 kHz DPSK acoustic data telemetry system developed at The University of Birmingham. The experiment was conducted across the Solent, at Southampton in the United Kingdom. The Solent is a extremely shallow channel with a severe multipath and high shipping noise. Excellent performance was obtained under favourable transmission conditions. The performance of the system is characterised by the bit error rate at various symbol and bit rates and ranges. The calculated performance is then compared to a theoretical model. The channel is characterised using ray theory in a constant temperature medium to initialise the impulse response, then randomly varying the delay and amplitude of the separate arrivals. This represents the effect of the fluctuating sea surface upon the reflected sound waves. The validity of this comparison is then discussed in the context of other published experimental work in this field