On geolocation accuracy with prior information in non-line-of-sight environment

Non-line-of-sight (NLOS) geolocation becomes an important issue with the fast development of mobile communications in recent years. Several methods have been proposed to address this problem. However, a comprehensive study on the best geolocation accuracy that these methods may possibly achieve is called for. In [1], [21, we reported a unified analysis of the Cramer-Rao Lower Bound (CRLB) and achievable bounds applicable to NLOS geolocation, assuming no prior information on the mobile station (MS) position or NLOS induced paths is available. In practice, however, we often have some information about these parameters beforehand. In this paper, we derive a lower bound for the geolocation accuracy in the presence of such prior information, and explore its physical interpretation. Some numerical examples are discussed.