Coherent integration method of frequency agile radar for target detection

Abstract

Frequency agile radar (FAR) has been widely used due to its good ability in anti-jamming and low probability of interception. However, FAR transmits pulses with agile frequencies, which will lead to random phase fluctuation and destroy the consistency between pulse-to-pulse radar echo. Aiming at this problem, a coherent integration method for target detection using FAR is proposed in this paper. 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 initial carrier frequency removed. After being matched filtered, the phase fluctuation due to frequency agility is eliminated. Consequently, coherent integration can be achieved by feeding the filtered signals to fast Fourier transform (FFT). Finally, numerical simulations are performed to verify the effectiveness of the proposed method.