Development Of Platform Based On WLAN And Study On Power Control In Mobile Ad Hoc Networks

Wireless self-organization network is one of the most important technologies in the beyond–3G era, and its performance can be improved by using power control. As the study of Ad hoc network goes deeper,the need for physical platform becomes eager. A lot of problems have been signed during the process of the realization of the power control technology, for example the hidden terminal problem and unidirectional link problem, and the distribution models are too ideal in some simulation.This thesis is organized as follows:1 .Base on the newest WLAN RF solution, we put forward a feasible system solution based on WLAN for Ad hoc network analysis and the physical platform RF module is fulfilled, consisted of a RF module, a core board of the control module, a peripheries board of the control module, driver and a test program. The experiments testify the system plan can meet the requirements of the self-organization network. 2. The development of power control technology in Ad hoc networks is introduced, three major problems in power control technology are studied, which are unidirectional problem, hidden terminal problem and nodes distribution problem. A novel multi-channel power control protocol based on density clustering with channel agents in wireless Ad hoc network(MCPCP) and a density-based clustering method employing MST are proposed . The MCPCP insure bidirectional links and avoid the hidden terminal problem brought by power control. MCPCP clusters nodes by means of the method based on MST, and the weight of MST is distance between two nodes.In a cluster, the weights of branch of the MST are similar and nodes share the same power level. Different clusters are signed in different channels. Different clusters communicate each other by channel agents. A model including from physics layer to application layer is built, which testified that MCPCP could work smoothly with 802.11 and AODV. Simulation results demonstrate the performance improvement. The physical platform works without a popular operation system. It could be difficult to add new protocol and application. The study of operation system for Ad hoc node should be on schedule. And the MCPCP does not optimize the transmitting power for modile nodes, the support to mobility should be study further.