Data fusion of target characteristic in multistatic passive radar

Radar cross section (RCS) is an important attribute of radar targets and has been widely used in automatic target recognition (ATR). In a passive radar, only the RCS multiplied by a coefficient is available due to the unknown transmitting parameters. For different transmitter-receiver (bistatic) pairs, the coefficients are different. Thus, the recovered RCS in different transmitter-receiver (bistatic) pairs cannot be fused for further use. In this paper, we propose a quantity named quasi-echo-power(QEP) as well as a method for eliminating differences of this quantity among different transmitter-receiver (bistatic) pairs. The QEP is defined as the target echo power after being compensated for distance and pattern propagation factor. The proposed method estimates the station difference coefficients(SDCs) of transmitter-receiver (bistatic) pairs relative to the reference transmitter-receiver (bistatic) pair first. Then, it compensates the QEP and gets the compensated QEP. The compensated QEP possesses a linear relationship with the target RCS. Statistical analyses on the simulated and real-life QEP data show that the proposed method can effectively estimate the SDC between different stations, and the compensated QEP from different receiving stations has the same distribution characteristics for the same target.