A novel redundancy technique for mobile networks

In a mobile network, the information transmission is done in a relatively noise and burst-error prone shared medium. The two methods commonly used to recover the transmission errors are automatic retransmission request (ARQ) and forward error correction (FEC). The ARQ is issued when errors exceed beyond those that can be corrected by FEC. ARQ implies re-transmission, which wastes a considerable amount of bandwidth and battery energy and creates an undesirable long delay, and can't be tolerated for certain services. We describe a spatial redundancy scheme in a mobile cellular network which is shown to greatly decrease the handoff call termination probability, the forced new call blocking probability and the ARQ probability. The basic idea is to add minimal number of redundant stations (Standby Stations: SS) at strategic locations in the cellular network topology. One of the potential location is the corner where the three adjacent three cells meet. Each SS could be "listening" and quietly monitoring activities on adjacent cells. These strategic locations could also be based on ground and signal profiles, so that fading signals could be easily restored by the SS.