Research Of Bandwidth Allocation Technology Based On Mobile Ad Hoc Network

Mobile Ad Hoc network, also known as mobile self-organizing network, is a multi-hop temporary autonomous system composed of mobile terminals with wireless transceiver, and works under the environment without a fixed structure. Because of the unique characters such as no need to set up network facilities, can be carried out quickly, strong survivability, mobile Ad Hoc network can be widely used in military communications, emergency search and rescue after an earthquake or flood and other applications.The first problem brought by the characters of mobile Ad Hoc network is the limited wireless transmission bandwidth. However, with the rapid development of communication technology, information transmitted in communication systems is in a sharp increase. Therefore, using the limited wireless bandwidth resources efficiently becomes increasingly important. At the same time, the quality of service (QoS) requirements by business are also increasing, so QoS guarantee is closely related and inseparable with bandwidth allocation.According to the system characteristics, network structure, application environment, the purpose of use and demand of mobile Ad Hoc network, this paper analyzes the current technology of network bandwidth resources allocation, and then a bandwidth allocation algorithm DPBA (Dynamic Priority-Based Bandwidth Allocation) based on dynamic priority is present, which is more suitable for clustering mobile Ad Hoc network compared with the original bandwidth allocation algorithm. This algorithm adjusts the using bandwidth dynamically in the system according to the priority of businesses. Therefore, there is no need to reserve bandwidth for business with high-priority so that there is no bandwidth waste; the algorithm implements strategy of seizing bandwidth, so as to ensure the transmission of real-time business such as voice business, and implements strategy of degrading service for data business to provide a more stable QoS. The simulation results elicited by NS2 show that, DPBA not only provides better QoS guarantee for high-priority voice businesses, but also reduces the block rate of data businesses with low-priority. Thus the algorithm implements the appropriate allocation of the bandwidth resources of mobile Ad Hoc network, which is partitioned into several clusters. Besides, the algorithm uses the wireless bandwidth resources fullest possible under the conditions of protecting different quality of service (QoS) requirement of businesses with different levels.According to the algorithm presented former, a simulation system is designed and implemented. The results show that the improved algorithm can reduce the block rate of the business on the aspect of users'data transmission.