A Channel Threshold Based Multiple Access Protocol for Airborne Tactical Networks.

Airborne Tactical Network is a promising and special mobile Ad hoc network, connecting the ground stations and all kinds of flying combat aircrafts on battlefield through tactical data links. Designing a low delay, large capacity, high flexibility, strong scalability, and multi-priority traffic differentiated medium access control (MAC) protocol is a great challenge in the researches and applications of ATNs. In order to overcome the disadvantages in IEEE 802.11 Distributed Coordination Function (DCF) and Time Division Multiple Access (TDMA) protocols, we present a channel threshold based multiple access (CTMA) protocol for ATNs in this paper. The CTMA protocol is a novel random contention type of MAC protocols, and it can differentiate multiple priority services, and utilize multi-channel resource based on channel awareness. We intensively describe the channel occupancy statistic mechanism, multi-queueing and scheduling mechanism of multi-priority services, and channel threshold based admission control mechanism involved in the protocol. We further derive the channel threshold of each priority service, the expressions of the successful transmission probability and mean delay mathematically. Simulation results show that the CTMA protocol can differentiate services for different priorities in ATNs according to the real-time channel state, and provide effective QoS guarantee for transmissions of various information.