On the localizability of cooperative positioning: Two user model

Cooperative positioning is a new paradigm in Global Navigation Satellite System (GNSS) positioning. By sharing information with other users and measuring geometrical range between them, the localizability and positioning precision of users can be improved. In this paper, we put forward a two user cooperative positioning model and a positioning algorithm. This paper analyzes the localizability of users and provides an exact and algebraic solution for two user cooperative positioning model. We theoretically prove that with the help of clock offset and altitude difference information, two users who can't be positioned by themselves can be positioned through cooperation. Simulation results illustrate that cooperative positioning can improve user's localizability largely. The results yield an important insight into the reason why cooperative positioning between users is beneficial.