| With the advantages of high date rate and low cost, WLAN has been widely usedeverywhere. However, due to the more and more dense deployment of AP (AccessPoint), WLAN becomes more and more crowed and the co-channel interferenceproblem gets more and more severe. Therefore, the study of dynamic resourceallocation should be necessary and urgent. This paper mainly studies dynamic resourceallocation strategies in high density WLAN, including channel allocation and transmitpower control. Firstly the research status of channel allocation and transmit powercontrol is briefly introduced and a detailed analysis of interference model andinterference scenario is made in this paper. Secondly, a typical utility-based channelallocation strategy and a graph-based channel allocation strategy are studied. Aimed atthe problem that the channel allocation based on graph theory is not suitable for highdensity situation, two improved methods are presented with detailed simulations andanalyses afterwards. Simulation results indicate that the improved methods can workwell in high density situation, reduce co-channel interference greatly and improve thenetwork throughput effectively. Thirdly, a RSSI-based transmit power control strategy isintroduced. Considering the unfair allocation problem in the scheme of maximizing thesum of SINR of all users, a fairness-based transmit power control algorithm isintroduced and a novel scheme based on maximizing the capacity of the whole networkis presented. Simulations of our two-step scheme based on our improved channelallocation strategy and both transmit power control strategies mentioned above aregiven. And simulation results show that in high density scenarios our scheme caneffectively reduce co-channel interference, guarantee the QoS demand of users andeventually improve the network throughput. Finally, a scheme joint considering bothchannel and power is given and then is preliminary realized and verified in a practicalWLAN environment. |
PDF Full Text Request