The Research Of Dim Targets Detection In The Over The Horizon Radar

The sky-wave radar is an over-the-horizon radar (OTHR) system. It uses scatteringfrom the ionosphere to detect or track targets far away. Nowadays, the sky wave OTHRshave been widely used in military (such as BVR warning) and civil (such as marinecondition monitoring). On the other hand, it is still a challenge to detect and track dimtargets under the complex ionosphere environment.It is quite different in the radar equation, parameters estimation method，detectingor tracking method compared to the general radar system. To solve such problem, we dothe main works as follows:Elaborated the OTHR radar equation, the maximum detection range and the radarfootprint. With the international reference ionosphere (IRI) model, it detailed therelationship between the ionosphere electron density and the parameters of the OTHRradar.The meteor trail echo is one of the main interference sources. It is difficulty tofilter it only on spatial domain. Discuss the meteor trail interference and develop amethod based on two composite hypotheses of Gabor coefficient to filter it. The methodis used to the real measurement data of a domestic OTHR radar and show effectiveness.The spectrum contamination of echo signal from the ionosphere distortion is a bigproblem in OTHR detection. The mechanism of the spectrum contamination from theionosphere distortion is exposed by analyzing the process of OTH-HF radar signalprocessing. Elaborate the tracking before detecting technology and the dynamicprogramming method. It develops an improved dynamic programming for extendedtargets.This article aims to solve the existing problems in the real data of domestic OTHRradar. It will play an important role in the development of the domestic OTHR radar.