G. S. Malyshkin, V. S. Melkanovich
Modifications of adaptive algorithms for resolution of weak signals (SNR <1) with a slight difference of arrival directions caused by an interference for a passive sonar are derived.
Adaptive algorithms are based on expression of likelihood function when signal is given by the plane wavefront with an unknown spectrum.
Normalized modifications of the expression allowing resolving of weak signals in the main lobe can be obtained by applying it to known algorithms.
Normalized modifications of Barlet, Capon, Borgoti – Lagunas, linear prediction algorithms, Jonson, MUSIC, minimum norm algorithms and projection algorithms are presented.
The possibility of detection and DOA estimation of weak signals in the main interference lobe is proved by computer si-mulation results.