Research On Downlink Inter-cell Interference Coordination Algorithms In TD-HSDPA System

In TD-SCDMA system,every cell/sector shares the same band, inevitably there exist interference among them, especially on the cell-edge zones whose performance have degradated heavily. Interference coordination technology aims to make the neighbor cells/sectors to use orthogonal resources by reasonablely resources allocation, so that, the inter-cell interference can be avoided. Interference coordination technology has low complexity and efficient. As the main source of interference in the future mobile communication system, investigating inter-cell interference coordination (ICIC) algorithms that easy to implement and low cost with high efficiency is of great significance.The purpose of this paper is to analys the interference in TD-HSDPA system,by reasonably coordinate the resources of TD-HSDPA system we designed two ICIC schemes: time interference coordination(TIC) and space interference coordination(SIC) to avoid downlink inter-cell interference in TD-HSDPA. In TIC algorithm, one cell/sector is divided into cell-edge band with higher inter-cell interference and cell-center band with lower inter-cell interference, each band carrys out discrete timely scheduling method with special power control strategy. The SIC algorithm executes scheduling in different direction against neighbors. By avoiding forming beam in a straight line between neighbors is a way to avoid inter-cell interference. Two algorithms are realized in TD-HSDPA system simulation platform on MAC layer. The simulation results show that the TIC and SIC algorithms are both simply implement and effective, and greatly improved the cell-edge users'average throughput and spectral efficienc .