Minimizing average network delay for ultra-wideband wireless networks

Ultra-wideband wireless (UWB) may provide the physical layer for high capacity personal area networks in the future. Certain characteristics of the wireless links possible using this technology give rise to properties not seen with other wireless technologies. Two such properties are long synchronization times for link establishment and the ability to change individual link capacities by choosing PN codes of different lengths. The paper formulates a novel routing problem in UWB; in particular, we investigate the impact of UWB physical layer characteristics on average network transit delay for a UWB network with a ring topology. The paper derives an expression for average network transit delay as a function of the capacity between each pair of nodes in the network. Each node is assumed to have one input and one output link resulting in a ring network topology, which guarantees access to every node. An aggregate network capacity bound for all links is assumed. A Lagrangian function is defined to obtain the optimum link capacities in order to minimize the average network delays and the resulting formula for delay is explained.