基于通信感知一体化的多基站无源协作感知技术

摘要：面向低空经济与智能交通等场景对高精度感知与可靠通信协同的迫切需求，研究了一种基于通信感知一体化（ISAC）的多节点无源协作感知技术。针对复杂环境下多基站协作感知中直射径[s1] （（LoS）径不稳定、时间偏移（TO）与载波频偏（CFO）不同步，以及多基站无源数据融合定位等挑战，构建了基于OFDM信号的多点无源协作感知信号处理方案。首先，采用2D-MUSIC方法实现到达角与离开角估计，并进行角度补偿与降维处理。其次，提出适配LoS不稳定场景的多点相位同步互相关（MPSCC）方法，有效抑制TO引起的测距模糊。在此基础上，设计多基站无源数据级融合定位算法，包括LoS存在时的椭圆-波达方向（DOA）联合定位法与LoS不存在时的到达时间差（TDOA）联合定位法，实现高精度三维定位。仿真结果验证了所提基于OFDM信号的多点无源协作感知信号处理方案的可行性，并表明了MPSCC方法的有效性。该研究为6G通感网络中的多节点协作感知提供了理论支撑与算法基础。

关键词：通信感知一体化；多基站协作感知；同步误差；数据级融合

Abstract: To meet the increasing demand for high-precision sensing and reliable communication in emerging applications such as low-altitude economy and intelligent transportation, a multi-node passive cooperative sensing framework based on integrated sensing and communication (ISAC) is investigated. In practical complex multi-base-station sensing scenarios, challenges arise from unstable line-of-sight (LoS) paths, asynchronous time offset (TO) and carrier frequency offset (CFO), as well as the lack of a multi-base-station passive data fusion localization method. To address these issues, an Orthogonal Frequency Division Multiplexing (OFDM)-based multi-point passive cooperative sensing signal processing scheme is established. First, angle-of-arrival (AoA) and angle-of-departure (AoD) are estimated via a 2D-MUSIC algorithm, followed by angle compensation and dimensionality reduction. Then, a multi-point phase synchronous cross-correlation (MPSCC) method adapted to unstable LoS conditions is proposed to suppress TO-induced ranging ambiguity. On this basis, a data-level fusion localization algorithm is developed, including an elliptical-DOA joint positioning method when LoS exists and a time difference of arrival (TDOA) joint positioning method when LoS is absent, enabling high-precision three-dimensional localization. Simulation results validate the feasibility of the proposed OFDM-based multi-point passive cooperative sensing signal processing scheme and demonstrate the effectiveness of the MPSCC method. Theoretical insights and algorithmic foundations for cooperative sensing in future 6G ISAC networks are provided by this framework.

Keywords: integrated sensing and communication; cooperative sensing; synchronization error; data-level fusion