| The heterogeneous network is a multi-layer network which access to a variety of network integration, so that the cell edge area and the specific areas can be strengthen. Multi-layer network structure is key research direction in LTE/LTE-Advanced. As a kind of flexible cheap way to access to the network, small cell can solve the problem of building and family indoor coverage effectively. Therefore, the heterogeneous network model which mainly treats the small cell as the mainly heterogeneous way of the heterogeneous network scenarios can effectively compensate the blind spot of the indoor scene for macro cellular coverage and improve customer communication quality. However, in this scenario, the widely use of the multilayer network makes the stress spectrum more stretched. So the frequency reuse strategies are introduced to the heterogeneous scenario. The suitable frequency reuse strategies can help heterogeneous network achieve the best performance and improve spectrum utilization, increase user capacity of community.This paper is to improve three frequency reuse strategies:Reuse-3, Fractional Frequency Reuse and Soft Frequency Reuse in the heterogeneous network model and find out the proper frequency reuse methods to the heterogeneous network model by the calculation and analysis. Furthermore, through the researching about the interference among the small cells, design a new dynamic frequency reuse strategy of small cells by the study the small cells grouping which can simplify the complexity of the dynamic frequency reuse strategy. The graph coloring method is considered to solve the key problems affecting small cell user capacity:the problem of the same frequency interference, so that to meet the business requirements of community users, and improve the system spectrum efficiency and throughput to the community at the same time. |
