A Matched-Filter-Based Coherent Integration Method for Passive Bistatic Radar Using Frequency-Agile Radar as the Illuminator

Abstract

Frequency agile radar (FAR) has been widely used due to its good ability in antijamming and low probability of interception, which will benefit passive bistatic radar (PBR) using FAR as the illuminator. However, the traditional moving target detection (MTD) method cannot be utilized by FAR due to the random phase fluctuation of its echo signals. To solve this problem, we propose a modified MTD method of PBR for target detection using FAR as the illuminator. This method first removes the initial carrier frequency of echo signals. Then a bank of matched filters are constructed according to the echo signals with the initial carrier frequency removed. After being matched filtered, the phase fluctuation caused by frequency agility is eliminated. Consequently, coherent integration can be achieved by MTD processing under certain criteria. Furthermore, the factors that affect the performance of the proposed method are analyzed. Finally, numerical simulations are performed to verify the effectiveness and validity of the proposed method in target detection.