Multi-path QoS routing in TDMA/CDMA ad hoc wireless networks

This paper investigates the issues of QoS routing in TDMA/CDMA ad hoc networks. Since the available bandwidth is very limited in ad hoc networks, a QoS request will be blocked if there does not exist a path that can meet the QoS requirements, even though there is enough free bandwidth in the whole system. In this paper, we propose a scheme of using multiple paths between two nodes as the route for a QoS call. The aggregate bandwidth of the multiple paths can meet the bandwidth requirement and the delays of these paths are within the required bound. We also propose three strategies for choosing proper paths, namely, SPF, LBF, and LHBF. Extensive simulations have been conducted. The simulation results show that the proposed multiple paths routing scheme significantly reduces the system blocking rates in various network environments, especially when the network load is heavy.