Space time adaptive processing for SONAR

University essay from Luleå/Systemteknik

Abstract: In both radar and sonar, in fact in all situations where an array of elements
is used, one of the interests is to locate targets both spatially and in
terms of velocity. In order to have a good estimate of a target's bearing and
velcity , the signal that is analysed has to be well measured, and well
suited for the kind of the analysis made. This thesis is carried out at FOI,
the Swedish Defence Research Agency. The goal is to implement a fully
adaptive space-time processor and identify the main difficulties and try to
explain them. Two different methods for handling the noise and interference
covariance matrix are described and evaluated. It turns out that the adaptive
processors outperform the conventional way of analysing signals, however to a
high computational cost. Still, many improvements are to be done and the main
field of interest should be the estimation of the covariance matrix and also
the estimation of number of interference sources.