A system jointly estimates states of GNSS receivers moving in a region using measurements of a Global Navigation Satellite System (GNSS). The system clusters the GNSS receivers into different clusters subject to a constraint on an upper bound on each cluster and executes a set of probabilistic filters corresponding to the set of clusters to estimate the states of GNSS receivers in each cluster. Each probabilistic filter estimates the states of the GNSS receivers in a corresponding cluster by fusing the GNSS data collected from the GNSS receivers in the cluster to jointly reduce an estimation error of each of the GNSS receivers in the cluster. The DES updates the cluster assignments based on a measure of estimation error in the states of different GNSS receivers in different clusters.