Research On Implementation Of MAC On Network Testbed Based On Software Radio

One of the main research methods for wireless networks is computer simulation.However, some study showed that the simulation has its limitations, and in some cases theresults are quite different from the actual conditions. It is even found that in practical radiochannels, the simulation results are indeed much different from the real situations withcomplex protocols at the physical layer and the MAC layer. Therefore, this thesis attempts toset up a wireless network testbed based on GNU Radio, to investigate how the physical layerprotocols and MAC protocols work in real channels. At present very little relevant materialcan be found in the literature, and this work can provide some reference for other researchers.The major focus of this thesis is the realization of the MAC protocols in this testbed, andit is composed of the following four parts. The first part is investigating the realcharacteristics of the channels, and building a simple wireless network experiment platform.The lowest layer of this platform uses the universal software radio peripherals (USRP) as itsRF, by which combining the software radio tool of GNU Radio, transmitting and receivingwireless signals can be completed. The second part is designing a MAC protocol based on the802.11MAC and its coding with the MAC frame encapsulation and decapsulation, etc., andrunning the MAC on the platform. The third part is testing and results analysis forenhancements, the verification of data transceiver and the service provided by the MAC layerfor upper layers. The results show that the basic functions of the MAC protocol have beensuccessfully achieved on the platform, and the MAC can provide good service for upperICMP protocol. The last part is the summarization of some experience in using the platform.