Spatial Anti-Jamming Based on Low Complexity Robust Beamforming via Orthogonal Projection

Abstract

To improve the spatial anti-jamming capability against the jamming signals, especially for those whose directions-of-arrival (DOAs) are close to the desired signal when the number of array elements is limited, a low-complexity robust beamforming algorithm via orthogonal projection (RBORP) is proposed by combining the control of the beampattern and the maximization of the output signal-to-interference-plus-noise ratio (SINR) in this correspondence. The RBORP algorithm has been theoretically proven to be capable of minimizing the upper bound of the actual amplitude response at the DOAs of jamming signals when the steering vectors are mismatched. Numerical results show that the RBORP algorithm exceeds the comparative beamformers with regard to the output SINR, and is capable of controlling the beampattern to shape precise and deep nulls at the DOAs of jamming signals. Numerical results also reveal the significant advantage of the RBORP algorithm in suppressing the jamming signals whose DOAs are close to that of the desired signal when there are fewer array elements.