Research On MAC Protocols For WLAN Based On CATV Network

CATV can provide data service over a large coverage area, and the coverage of CATV deployment is very good . WLAN can provide high-speed data service, and it has other advantages such as flexible network framework, license-free radio spectrum and low-cost network equipments. But its coverage is small. So the integrated WLAN and CATV can combine the advantages of the two technologies, and it can provide the customer with cheap, ubiquitous wireless services with high data rates. In order to acquire large mount of information via to advanced technology, besides its enlarging information resources and speeding access speed, there are a kind of costly and efficiently broadband access networks, a tremendous opportunity exists with broadband over HFC network.At first, the paper described the characteristics of HFC transition. Then mainly focuses on the difference of WLAN and CATV . It design the access scheme of WLAN for CATV based on IEEE802.11. The research subject of the paper is the key function layer of the WLAN network-MAC layer. It improves the access of WLAN to CATV from different ways, for example, Improve transmission efficiency , subtract postpone, improve the capacity of downlink , improve transmission capacities of uplink , diminish the collision and so on. From the point of the theoretical analysis and the computer simulation, the MAC protocol of the subject to HFC system are thoroughly studied.The improved 802.11 MAC protocol of subject to CATV network is used for small area wireless coverage, it is extremely valuable and economical that the operators provide Internet access, TV broadcasting service, data exchange service, video on demand (VOD) service and other normal telecommunication traffic by WLAN as supplying for HFC networks simultaneously.