Coherent Detection in Sea Clutter Given Acquisition Data for Long Duration

Because the sea clutter returns acquired for a long duration cannot guarantee the time-stationarity, the estimation performance for the CCM(clutter covariance matrix) is apt to deteriorate even if a sufficient number of secondary data vectors are provided. This paper presents a detection method with clutter-corrupted target returns for a long duration. This is accomplished by dividing the long acquisition period into a number of shorter periods that maintain the time-stationarity so that the CCM for each short duration can be more accurately estimated. To improve detection performance, we show that maximum SINR(signal to interference plus noise ratio) filters designed with the estimated CCMs are applied to each data for a short period and the filter outputs are coherently combined. The improvement in the SINR at the target Doppler bin is theoretically analyzed and verified by simulation.