An EM algorithm for hop timing estimation in FH networks with frequency collisions

Frequency collision is unavoidable in frequency hopped (FH) wireless ad hoc networks as the number of nodes increases, which may cause reduced throughput and excessive delay. In this paper, we develop an expectation-maximization (EM) algorithm to jointly estimate hop timing and frequencies of multiple FH signals in the presence of collisions. The algorithm does not require the knowledge of hop patterns and hop rates of the users, hence it enables robust FH wireless ad hoc networking in a noncooperative environment.