Long-Time Coherent Integration for High-Order Maneuvering Target Detection via Zero-Trap Line Extraction

In the study of long time coherent integration (LTCI), there have been many methods, which tend to complete the detection and parameter estimation of high-order maneuvering target by transforming the echo of target to the range-frequency and azimuth-time (RF-AT) domain. Unfortunately, serious parameter coupling will occur in the RF-AT domain, which is not easy to handle. In order to avoid parameter coupling, a LTCI algorithm based on the extraction of zero-trap line (ZTL) in 2-D spectrum is proposed for fourth-order maneuvering target detection. The echo spectrum of the fourth-order moving target is derived, and the spectrum formula contains some special terms that can be used for target detection. ZTL is a line of data, which caters to those special terms and is only related to the speed of target. The extraction of ZTL can simplify the matching function constructed by the estimation of other motion parameters. Finally, both computer simulations and numerical results verify the effectiveness and superiority of the algorithm at low signal-to-noise ratio.