SMLRT-GRT-SVD Based Sea-Surface Slow and Small Target Signal Integration and Clutter Suppression Method for Airborne Radar

‍ ‍Airborne radar faces two main problems in sea-surface slow and small target integration detection： First， the relative motions between radar and target lead to range walk and Doppler spread， which result in target integration performance degradation. Second， the heavy sea clutter background energy affects the focusing and detection results. To solve the above problems， this paper proposes a method （i.e.， SMLRT-GRT-SVD） based on segmented modified location rotation transform （SMLRT）， generalized Radon transform （GRT） and singular value decomposition （SVD） to quickly realize integration detection and clutter suppression. Firstly， a time division criterion is designed to segment the echo signal evenly， and the second-order range walk and Doppler spread caused by radial acceleration can be ignored in each slice. Secondly， SMLRT is used to correct the first-order range walk of each slice resulted from the radial velocity， and Fourier transform （FT） is conducted to realize the energy coherent integration in each time slice. Thirdly， apply GRT to track the energy peak positions of all time segments and carry out non-coherent integration. Finally， utilize SVD to decompose the echo signal in the slow time domain and eliminate the corresponding singular values of clutter. After reconstruction， the sea clutter energy can be suppressed. In this method， segmenting processing and SVD operation are adopted to quickly achieve the target energy accumulation and suppress the sea clutter energy. Simulation and real data processing results show the effectiveness of the proposed method.