Radar Matched-Filter Properties of Phase-Switched Screen at Arbitrary Phase Modulation Angle

Phase-switched screens (PSSs) achieve low detectability for protected targets by intermittently modulating the phase of incident radar waves, altering their scattering characteristics. Current research on PSS predominantly focuses on the ideal 180° phase modulation, which effectively suppresses the central frequency component of the radar signal. However, achieving this theoretical modulation angle at nonresonant frequencies is challenging for practical materials, limiting the broader application of PSS. This article investigates the modulation mechanism of PSS at arbitrary phase angles. A comprehensive phase modulation model is developed to analyze the impact of various parameters on the matched filtering process of radar signals. The theoretical derivation reveals that the modulation angle serves as a critical energy parameter, primarily influencing the amplitude coefficient of false peaks generated after matched filtering. The study has established the mapping relationships between characteristic parameters (modulation angle, modulation frequency, and duty cycle) and the radar matched-filter output as well as radar sensor performance metrics. To validate these findings, a simulation study is conducted across the time domain, frequency domain, and matched filter output, demonstrating the feasibility and effectiveness of arbitrary-angle phase modulation in PSS design.