A Flexible Range–Doppler Modulation Method for Pulse-Doppler Radar Using Phase-Switched Screen

The time-varying phase-switched screen (PSS) has demonstrated a significant potential for modulating radar target features, due to its exceptional capabilities in the harmonic generation and control. However, most existing studies focus on single-dimensional target features, with limited investigation into joint modulation of 2-D or higher dimensional features. In this article, a time-domain digital coding PSS system is proposed. By applying 1-bit periodic phase modulation, the spectral energy of the incident electromagnetic (EM) wave is redistributed across multiple harmonics, thereby simultaneously influencing the detection of range and velocity features by linear frequency modulated (LFM) pulse-Doppler (PD) radar. Through the precise control of the energy and frequency-domain distribution of these harmonics, radar false targets exhibiting coupled range-velocity features can be synthesized in the feature space. Leveraging this coupling characteristic, the method enables flexible feature modulation, including EM cloaking, range modulation, Doppler modulation, and range–Doppler (RD) 2-D joint modulation. Simulations demonstrate the effectiveness of the approach, revealing that the primary false targets remain detectable even at low signal-to-noise ratios (SNRs), despite a reduction in the number of effective false targets. Finally, a practical countermeasure experiment conducted in a microwave anechoic chamber further validates the feasibility and effectiveness of the proposed method.