A fuzzy inference system for the handoff decision algorithms in the virtual cell layout based tactical communications systems

A novel handoff decision algorithm, namely multicriteria handoff decision algorithm (MDA), for the virtual cell layout based mobile subsystem of the next generation tactical communications systems is introduced. In this algorithm, handoff decision metrics are received signal strength measurements from the access points, soft capacities of the access points, and relative directions and speeds of the access points and the base transceivers. Soft capacity of an access point is affected by the interference in the environment. We use a fuzzy inference system to process these metrics. We compare our algorithm with the received signal strength based handoff decision algorithms. Our tests have shown that MDA with lowest membership value threshold achieves minimum number of handoffs, and MDA with highest membership value threshold achieves minimum call blocking rate (GoS), where the call blocking rate is still in an acceptable level in the former case and number of handoffs is in an acceptable level in the latter case.