Satellite-based PCL for moving target detection using keystone transform and FrFT

This paper presents a moving target detection technique for passive radar with satellite transmitter of opportunity and stationary receiver. The proposed technique relies on a proper processing of the data aiming at, first, correcting the range cell migration over the received echo, and then, transiting in a proper domain where the moving target can be isolated from the disturbance contribution. The former goal is obtained by applying the keystone transform. Then, the range compressed-slow-time data are transformed to Doppler centroid (DC)-Doppler frequency rate (DFR) domain via fractional Fourier transform (FrFT), where the coherent integration gain can provide enough SNR for the target detection. Ultimately, it is suggested that a proper processing of a long stream of data can increase the SNR making possible also the detection of low RCS targets. Numerical simulations show the effectiveness of this target detection technique to be employed for example in maritime surveillance frameworks.