2D-Rake MMSE receiver for burst communications through multiple-access shallow-water channels

This paper suggests a spread-spectrum based receiver architecture that employs both spatial diversity and rake reception, in order to achieve reliable communications through multiple-access shallow-water acoustic channels. The key idea is to improve system performance by exploiting the multipath profile and combining, rather than canceling, the energy arriving at the receiver via bottom and surface reflections. The optimization of the receiver parameters is achieved by employing the minimum mean-square error (MMSE) criterion. Results indicate that the suggested receiver algorithm can dramatically reduce the number of receive elements required without any significant loss in performance. However, this is achieved at the cost of increased computational complexity.