Method for bearing estimation of target for amplitude modulation radio-based passive radar application
In a passive radar system, the bearing of the target is difficult to measure for the signal-to-noise ratio of the target's echo signal is generally very low in practise. A novel method to estimate the echo signal's angle is proposed. The cross-ambiguity function of direct-path signal and each antenna's receiving signal is calculated to form a virtual array signal, in which the desired echo signal can be enhanced at a certain time delay and Doppler shift, so it is able to estimate its angle. We make the theoretical analysis about how the desired echo signal is enhanced. Some experimental results of an amplitude modulation (AM) radio-based passive radar are presented to verify the effectiveness of the proposed method.
