Robust pointing error compensation technique based on rooting method for CDMA signals

A robust pointing error compensated algorithm for code-division multiple access (CDMA) signals is proposed. Theoretically, minimum variance distortionless response (MVDR) beam-former can achieve the maximum power. However, it is very sensitive to pointing error for the large SNR. In order to deal with the desired signal cancellation problem, the differential rooting method is used to estimate the pointing errors and self-compensate them. Since the proposed method can reduce the estimated pointing error, it performs better than the conventional rooting method and the spectrum searching method in high signal to noise ratio (SNR) and large multiple access interference (MAI) scenarios. Several computer simulations are provided to illustrate the effectiveness of the proposed method.

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