GNSS Adaptive Beamforming Including Null-steering for Unwanted Signal

Unwanted signal such as spoofing, jamming, and multipath is one of the major error factors in GNSS positioning. The purpose of this research is to mitigate the unwanted signal especially multipath error using an array antenna with six elements. We verified the effectiveness of the DCMP (Directionally Constrained Minimization of Power) algorithm to mitigate the unwanted signal. DCMP algorithm is one of the signal synthesis methods using the array antenna and can direct the ``Null'' to the unwanted signal direction by setting some constraint conditions. Testing in multipath-rich environment showed that the positioning accuracy was improved by constraining the ``Null'' toward the building which reflected GNSS signal.