Technique for the estimation of PC clock offset in a GNSS-aided network of collaborative users

“Peers-based aiding GNSS” refers to collaborative systems composed by GNSS receivers that exchange aiding data in order to improve their performance. One of the main issues related to this type of systems is the time synchronization between receivers. The required precision of the synchronization depends on the type of data the receivers exchange. This paper presents a new technique devoted to solve the synchronization problem in a network of collaborative users, equipped with low cost GNSS receivers. Such a technique is based on the joint processing of the same GNSS signal received at different nodes of the network and exploits some attributes of the GNSS signal to evaluate the synchronization offset. The paper describes the new technique with the appropriated theory and gathers the results of some measurements performed in a real scenario. Moreover, on the basis of the clock offset estimate, an acquisition algorithm for aided GPS systems has been developed and tested in a real indoor application.