The Effect of Channel Mismatch and Mutual Coupling on GPS Adaptive Antenna Array

In order to design the receiving channel of the GPS adaptive antenna array, it is necessary to analyze the effect of channel mismatch and antenna mutual coupling on SINR (Signal-to-Interference-plus-Noise Ratio) and ICR (Interference-to-Cancellation Ratio). In term of the signal environment of GPS, the expressions of SINR and ICR are conducted in existence of the deviation and the perturbation of the HF channel Amplitude/Phase (A/P), I/Q imbalance and the antenna mutual coupling by using the orthogonality of weight vector and the jammer space. It is proved that ICR is mainly determined by the HF channel A/P perturbation and the I/Q imbalance, but almost independent of the HF channel A/P deviation and the mutual coupling, and the calibrations for the deviation aren't always increase the SINR and the correction for mutual coupling can get the benefit of SINR just proportional to the maximal singular value of Scattering matrix. The simulation results on the aspect of the above are given.