Research On Clustering Method For Base Station In Heterogeneous Wireless Networks

In order to meet the performance requirements of 4G,3GPP based on the LTE,LTE-Advanced was launched.By introducing a series of key technologies to achieve the target of maximum bandwidth of up to 100 MHz,and the rate breakthrough1 Gbps,and the application of heterogeneous network, collaboration multi-point transmission technology, MIMO technology will bring a better experience for users and higher system throughput.In the process of the development of mobile communication technology, the inter-cell interference is always the key problems needed to be solved, especially the network structure of the heterogeneous network, for the addition of more sites, will lead to greater inter-cell interference(ICI) and more frequent switching.The collaboration multi-point transmission technology gives a new way to the above problems, with the application of CoMP technology, which could change the interference signal into effective signal,then improve the edge of the user's transmission rate, and improve overall system throughput.This paper research on the downlink transmission system in heterogeneous networks,The simulation model is established Based on the position coordinates in heterogeneous networks.And on the basis of this model,proposing clustering method of threshold and fractional step. To put in the system area is divided into a series of residential cluster, in these clusters base stations within the common effective signal transmission for the user.The clustering method based on threshold considering the effect factors of base station numbers, the base station signal intensity target user belongs to, and the system of interference,and then setting the threshold value, when the user receives the base station signal strength is higher than the threshold, then the base station was elected to the base station clustering.By reducing the user's selection range,the fractional step clustering method firstly analysis the signal interference of the rest of the base stations in addition to the main service stations of the desired user,and determine the collection for clustering base station;Then according to the signal intensity of each base station in the collection of the desired user received to determine the final participate collection of the collaborative base station.The simulation results show that the base station clustering scheme in the heterogeneous network structure,which makes the edge users obtain higher transmission performance.