Distributed Multistatic Passive Radar Signal-level Synergy Target Localization Technology

Utilizing existing electromagnetic signals in the environment, distributed passive synergy surveillance means zero-power silent surveillance of targets can be conducted. This significantly enhances radar′s low interception and anti-jamming capabilities, making it one of the key development directions in multi-radar synergy surveillance technology. Currently, passive synergy localization primarily faces challenges such as weak target echoes, unknown parameters of non-cooperative transmitters, and direct-path interference. A signal-level high-precision target localization method for distributed multistatic passive radars is proposed in this paper to address these issues. This method involves combining dual-channel signals received by multiple passive radars to establish a signal-level target position estimation problem, achieving joint direct-path interference suppression and high-precision estimation of the external transmitters and target positions, thus forming a zero-power silent synergy surveillance capability for distributed multistatic passive radars. Additionally, sequential and alternating iterative estimation strategies are used to reduce the high-dimensional estimation problems to multiple low-dimensional ones, lowering the computational complexity and enhancing the real-time localization capabilities. Simulation results indicate that compared to data-level localization, the proposed signal-level method demonstrates superior performance in low signal-to-noise ratio and direct-path interference environments. The proposed passive synergy localization method can be applied in scenarios such as UAV silent surveillance, anti-low-altitude, and anti-stealth targets, which can significantly enhance surveillance and strike capabilities against enemy targets.