Resource Allocation In Wireless Ad Hoc Networks

There continues to be rapid adoption of wireless technology, and when coupled with the explosive growth of the Internet, it is clear that there will be increasing demand for wireless data services. How to fairly and efficiently allocate and manage its resource is crucial for WANET to provide satisfactory diversified services for end users. The shared-medium multi-hop nature of wireless ad hoc networks poses fundamental challenges to the design of effective resource allocation algorithms that are optimal with respect to resource utilization and fair across different network flows. In this thesis, the study objective is set on the resource allocation for the multi-hop wireless ad hoc networks. Our work starts with the discussion of characteristics, objective and constraints of resource allocation in multi-hop wireless ad hoc networks. In addition, three models on resource allocation for WANET, such as max-min fair scheduling, rate-based controllers and a price-based approach, are studied and compared on their theoretical framework, characteristics, fairness and utilization.In this thesis, we propose an efficient bandwidth allocation scheme called Active-Time based Bandwidth Allocation among Scheme (ATBAS) that can ensure fair bandwidth allocation among the users in a multi-hop WANET model. This scheme operates at each hop and fairly allots each competing flow a share of channel time, according to which each hop and records their updated rate for each flow traversing the hop and records their updated rates into each data packet's special control header. The source of each flow in this scheme can eventually adjust its sending rate to reach its fair share. An algorithm is developed to implement the above mechanism. We will show through simulation results that our proposed algorithm is able to fairly distribute bandwidth among multi-hop flows.Max-min fairness is an important requirement for multi-hop WANET, that demand totally equal treatment of users regardless of the number of hops they travel. To control the flow rates in a fully distributed manner, our new price-based rate allocation scheme achieves max-min fair rate allocation in wireless networks by applying the MaxNet idea and considering the unique constraint of wireless. Mobility of wireless networks generally leads to variations of topology;our proposed algorithm is shown to be adaptiveto the routing changeovers arising from the mobility of wireless networks in the sense that the rate allocation is still able to maintain max-min fairness for wireless mobile networks. Furthermore, it facilitates implementation due to its distributed nature. Through theoretical analyses and simulation results, we show that the algorithm is able to meet the wireless constraint and to achieve max-min fairness among multi-hop flows in wireless networks even if the topology varies, as is the case in a mobile environment.We also extend pricing rules in wireless networks and present a more general formulation, which subject to the MAC constraint in networks with arbitrary topologies, or subject to more general clique constraints.