WEAK TARGET DETECTION IN STRONG BACKGROUND FOR OTH RADAR

HF OTH radar can accomplish surveillance over the horizon. But backscatter signal that is output from receiver may contain strong noise and interference background. Especially, these impulsive interferences such as lightning may inject transient and great power into the receiver, arise the noise floorin the range-Doppler map and decrease SNR. So these powerful interferences must be suppressed before target tracking. Many solutions are present for these excisions. Meanwhile the strong ocean clutter must also be firstly suppressed. Different from these approaches at present, this paper proposes a novel algorithm of direct detection without in advance depressing clutter and these impulsive interferences. The main idea is focused on the different local regularity between target return, interference and noise. Herein the combination of Lipschitz exponent and CWT is NOT for noise suppression and interference detection in popular techniques any more, but used for the local regularity estimation and signal classification.