Channel-level STAP Method For Lofty Target Detection Of Missile-borne Wideband Phased-array Radar

Clutter suppression and ship target detection which has obvious characteristics compared with the height of the sea surface are key issues to be addressed of hypersonic anti-ship missile guidance radar.High resolution imaging and phased array space-time adaptive processing(STAP)are important approaches to solve the above problems.Missile borne high resolution imaging and phased array STAP are research hotspots in the field of radar signal processing.Aimed at the application of wideband phased array radar in missile borne platform,the research on theory and its technology realization way of clutter suppression,target detection and angle measurement,has great academic and practical value.Based on missile borne wideband high pulse repetition frequency-stepped frequency phased array mono-pulse radar and hypersonic high dive to sea attack application background,channel-level STAP method and its application in clutter suppression,the lofty target detection and angle measurement are studied systematically in this paper.Specific research and results of thesis are as follows:(1)For missile borne wideband high repetition frequency-stepped frequency phased array mono-pulse radar and hypersonic high dive to sea attack application background,the range-height coupling effect and the Doppler-height coupling effect of lofty target are studied.Aiming at the problem that the existing space-time adaptive processing methods are difficult to improve the performance of static target detection,it is pointed out that the feasibility of improving the performance of the static lofty target detection by space-time adaptive processing method.(2)For two-dimensional range-Doppler imaging of wideband high repetition frequency-stepped frequency radar,we proposed a parameter design scheme based on non-fuzzy velocity measurement within isometric ring and a motion compensation method based on the center radial velocity of clutter isometric ring.The proposed method can improve the precision of motion compensation and satisfy the need of non-fuzzy velocity measurement in each isometric loop.(3)Aiming at the high range resolution and low velocity resolution characteristics of range-Doppler imaging for missile borne wideband radar,channel-level STAP method in pitch direction is proposed to suppress clutter and detect lofty target.It carries on range-Doppler imaging of sum channel and difference channel first.Then,the adaptive cancellation technique is adopted to suppress clutter.At the same time,the modified sum channel and the modified difference channel are formed by digital processing.We can detect targets from the modified sum channel.For shift angle flicker effect of lofty target,the new STAP method is proposed to measure the target azimuth angle by using the single pulse ratio between the modified sum channel and the modified azimuth difference channel.Compared with the traditional STAP method,this method can realize the compatibility between the clutter suppression and the traditional single pulse angle measurement.Moreover,it is of low computational complexity and easy to implement in missile platform.(4)The effectiveness of the proposed method is simulated and evaluated through MATLAB experiments.The relationship between clutter suppression performance and target angle estimation accuracy,and signal to clutter ratio and target height are analyzed,which provides an important reference for the precise detection of terminal guidance for missile borne phased array radar seeker.