Inter-Device Interference Mitigation for mmWave Sensing with Multi-Domain Analysis

mmWave sensing is a promising technology that could sense target states wirelessly. However, the increasing deployment of mmWave devices exacerbates inter-device interference (IDI), making it difficult to detect the presence of a target. To address this issue, we delve into the underlying mechanism of the IDI through a multi-domain analysis on the received mmWave signals. Through the exploration, we reveal the temporal sparsity of the IDI, the frequency sparsity of the target echoes, and the spatial separability between them. Exploiting these characteristics, we propose a novel multi-domain IDI mitigation method. Specifically, by leveraging the spatial separability of the IDI and the target echoes, we develop a non-IDI detection based spatial focus strategy, which detects and leverages the non-IDI segments to estimate the azimuth of target echoes for weighted coherent accumulation. Furthermore, by leveraging the temporal and frequency sparsity of the IDI and the target echoes, we develop a time-frequency sparse signal decomposition algorithm with diverse observations, which fully utilizes the signal characteristics and antenna diversity, to separate and reconstruct the target echoes while mitigating the IDI and noise. We design a 60GHz mmWave sensing system and conduct extensive experiments to validate the effectiveness and performance of our proposed scheme. © 2026 IEEE.