A Low-Complexity Approach for Range-Doppler Sidelobe Suppression With Radar-Centric ISAC Waveforms

Multifunctional radar with Integrated Sensing and Communication (ISAC) capabilities represents a key direction in the evolution of future software-defined radar systems. However, the presence of random communication information introduces significant clutter in the Doppler dimension during coherent accumulation. Under strong scatterer echoes, this clutter may cause numerous false alarms or obscure weak targets that would otherwise be resolvable in the Doppler domain, posing a critical challenge for radar performance. To address this issue, we propose a simple and effective algorithm termed Spectrum Windowing Whitening Filtering (SWWF). The proposed method effectively eliminates the influence of embedded communication signals while suppressing range sidelobes. Its computational complexity is comparable to that of conventional matched filtering, ensuring compatibility with existing radar architectures. To validate the effectiveness of the proposed algorithm, we conducted field experiments on unmanned aerial vehicle (UAV) detection. The results demonstrate that SWWF significantly reduces Doppler-domain clutter and improves the detectability of weak targets in the presence of strong interference, thereby enhancing the overall robustness and reliability of ISAC radar systems.