| This thesis focuses on the performance and design of Ultra Wide Band (UWB) wireless networks. UWB networks, a technology suited for high data rate, low-power applications, has drastically different physical layer characteristics from existing networks, and hence merits a detailed investigation.; We begin by studying the information theoretic uniform throughput capacity, a critical parameter for the design and evaluation of ad-hoc wireless networks. Assuming a limiting UWB model, we demonstrate that the uniform throughput capacity increases with node density, in contrast to prior pessimistic results. This dramatic result justifies the promise of UWB for dense wireless networks and motivates an investigation into the effect of the UWB physical layer on the various networking layers.; We next analyze traditional link layer algorithms, with the incorporation of the physical layer into the network model. The resultant deteriorating performance bounds in the low Signal to Noise Ratio (SNR) regime, typical of UWB systems, indicates the inadequacy of existing networking models and algorithms for UWB networks. Hence, to develop optimal UWB networking (link and routing) algorithms, we cast a cross-layer optimization problem that incorporates the network (routing), link (scheduling) and physical layer (UWB based) funetionalities. We then solve this novel but hard optimization problem and demonstrate interesting solutions for sample networks. The quantitative and qualitative results, from this optimization perspective and the prior information theoretic perspective, are shown to be consistent.; The tools and intuition we develop, are applied to a practical problem of current interest. The relative performance of two competing physical layers (802.11n and UWB), in home or office wireless networks is analyzed. The effective network performance based choice, is a sample of the flexibility and utility of this thesis. |
