Application of geometric algebraic projection operator in radar complex signal processing

Abstract

A variable projection angle is obtained based on the geometric algebra (GA) projection operator using the geometric meaning of complex vectors’ inner product. Considered that the inner product processing is widely used in radar applications, i.e., radar signal detection and matched filtering, a geometric detector, and a geometric matched filter are proposed based on the projection angle in the GA framework. Several simulations, as well as experiments, confirm that the proposed geometric detector overperforms the traditional constant false-alarm rate (CFAR) detector, especially in the uniform background, and in adaptions to the clutter edge and large dynamic change of signals. Moreover, the higher efficiency of the geometric detector is indicated by the analysis comparison of computation complexity, which indicated that the geometric detector possesses higher efficiency than the traditional CFAR detectors. The response characteristics of the geometric matched filter for intermittent sampling and repeater jamming (ISRJ) are also validated through theoretical and simulation analysis. The presented results provide a geometric perspective for solving the design of radar detectors and the suppression of ISRJ.