A Hybrid BP-VMP-EP Localization Algorithm for Passive MIMO Radar Networks

A passive multiple-input multiple-output (MIMO) radar (PMR) network is an efficient system to detect and track targets, which consists of multiple distributed receivers and illuminators of opportunity. Conventional two-step localization first estimates the distance based on signal time delay mea-surements, then the location is obtained by using least square or maximum likelihood estimator. Recently, several works show that through direct localization, performance can be significantly improved. For a better balance between accuracy and complexity, in this paper, we propose a hybrid message passing localization algorithm. Derived from a Bayesian inference framework, the proposed method can be regarded as an iterative version of two-step methods. Simulations show that the proposed algorithm outperforms conventional two-step localization, and provides a trade-off between position accuracy, communication overhead and computational costs.