Architectures and protocols for UWB based wireless networks
UWB technology offers advantages including high bit rates, low power, robustness to multi-path fading, precise ranging/tracking ability, and low-complexity transceivers. Based on these advantages, UWB holds a great promise to revolutionize the next-generation wireless networks. To successfully realizing a UWB network, we propose architectures and protocols for different types of UWB networks.
For the high-speed UWB networks, we are the first to propose and evaluate a centralized MAC protocol that provides explicit QoS support. The proposed protocol, which comprises of a time slot scheduling algorithm and a resource control algorithm, differentiates between allocates QoS (i.e. real-time traffic) and BE (i.e. Best effort traffic) traffic and accounts for the UWB unique characteristics.
Next, we introduce a distributed MAC protocol that assigns a flexible bit rate and accounts for network and traffic dynamics as well as the requirements of future links. To the best of our knowledge, no such flexible bit rate MAC protocol has been documented.
Although single channel UWB networks possess the benefits including simple transceiver and robustness to multipath fading, multichannel UWB networks have the flexibility of multichannel operation. For multichannel UWB networks, we propose a MAC protocol that emphasizes on QoS support in multichannel networks. Applying a two-phase procedure, the proposed protocol is capable of optimizing the resource utilization in dense networks and providing explicit QoS support.
Because of UWB's precise ranging/tracking ability, the UWBbased low-speed network is often used to provide high-precision indoor location service. Hence, we propose a hierarchical architecture for UWB based indoor location. Unlike the existing works that focus on signal processing and device level implementation, our work is the first to emphasize on proposing architecture for UWB based low speed networks.
We have implemented each proposed solution in the simulation. Using the simulation models, we evaluate the each solution and analyze the impact of system issues such as traffic load, traffic distribution as well as system parameters. The simulation results show that comparing with existing methods, our proposed solutions show significant advantages. Based on the results and insights we have built, we propose some future research directions at end of the dissertation.