Vaa Cell Division

Multiple-Input Multiple-Out-put technology (MIMO) can be used in the wireless communication network to not only offer the potential of high system capacity, but also lesson the severe effects of noise. Virtual MIMO is extended from MIMO, also known as virtual antenna array (VAA) technology. Its advantage lies in: VAA breaks one limit, that is, the fact that the fades from any transmit to any receive antenna are uncorrelated and of different strength. Its essence is cooperative diversity, can be seen as a signal processing technology and network technology to some extent, the related study still in its infancy, there're many important issues need to be solved in virtual MIMO, such as lack of systematical research on forming VAA groups. In the paper refers to constract VAA groups, the main contributions are as follows:1. With aid of the existing clustering ideas in Ad Hoc network, a new model of VAA groups is designed.The main communication performance of capability is analyzed and compared with the typical VAA groups model in detail by MATLAB simulation and results are summarized.2. From the cross-layer design of cooperation, first of all, give the total scheme from the source terminal to the destination to the purpose of the whole VAA mechanism, that is, with the aid of current network clustering algorithms, it selects a designing method with cluster heads; Secondly it choose the main path nodes using the current routing protocol, as VAA groups'cluster heads, then suppose the cluster heads known, it can build VAA group using of one topology discovery alogrithms.And from the simulation results, we can draw the approach is feasible under some condition, by network simulation NS2; Thirdly, the essay advanced discusses to research VAA groups by improving neighbor lists and routing tables; what's more, it points that forming VAA groups by smart antenna technologies in infrastructural networks.