Dynamic channel assignment in clustered multihop CDMA/TDMA ad hoc networks

A good channel assignment scheme in a multihop ad hoc network should not only guarantee successful data transmissions without collisions, but also enhance the channel spatial reuse to maximize the system throughput. It becomes very inefficient to use fixed channel assignment when the network size grows. Therefore, spatial reuse of channels becomes more important in a large multihop ad hoc network. We consider an ad hoc network with an overlaid CDMA/TDMA structure. We divide each code into time slots to form the channels. Two dynamic channel assignment (DCA) strategies, called greedy-based DCA (GB-DCA) and channel segregation DCA (CS-DCA) are proposed in a clustered wireless multihop ad hoc network. These DCA strategies are designed to make better use of available channels by taking advantage of the spatial reuse concept. We show that the bandwidth saving due to channel spatial reuse is higher than the additional bandwidth spent on the control overhead.