Research On Interference Coordination Technologies Of Heterogeneous Networks In LTE-Advanced

With the rapid development of today’s wireless communications, the fact is that broadband wireless network will be in an exponential growth in traffic, and the network is bound to demand greater data rates and higher coverage quality. So3GPP proposed heterogeneous network technologies in LTE-Advanced standardization process to meet this demand, so as to enhance the overall network performance. As a new networking mode, Heterogeneous networks overlap on the macrocell network deployment with low-power nodes, such as Pico node, femtocell, relay, Remote Radio Head (RRH) and so on, to shorten the distance between the base station and the end-user. This can effectively improve the cell splitting gain and spectrum reuse efficiency, so as to enhance the quality of the coverage of the hot zone. Low-power nodes have small transmission power and low-cost construction, is green, and will be in large-scale use in the future. Heterogeneous network brings technological change in network system, but also brings technological challenges.The main target of this paper is to research the interference coordination technology in heterogeneous networks of LTE-A system. By introducing networking model of heterogeneous network, we concerned about the inter-cell interference problem caused on the main scene in LTE-A heterogeneous network. Concerning the Heterogeneous network scenario for LTE-A in which macro base stations and outdoor Pico node co-found, we study its serious interference problem, and propose enhanced inter-cell interference coordination(eICIC) program, including the frequency domain, power control, and time domain interference coordination techniques, to reduce the level of inter-cell interference. The time domain interference coordination technology adopts Almost Blank SubFrame (ABS) scheme, including static ABS configuration schemes, as well as adaptive ABS ratio configuration scheme which is independently proposed in this paper. Macro base stations will be self-applicable to configure ABS ratio adaptively, according to the number of Pico users which bear serious interferenc around the macro base station, thus enhancing the overall throughput of heterogeneous systems and edge user performance just on the premise of reducing the macro’s throughput rarely.In this paper, I build LTE-A system-level simulation platform of heterogeneous network, and add the Cell Range Expansion (CRE) scheme, ABS schemes, as well as the Cell Reference Signal (CRS) interference calculation, to simulate the improvement of system performance by adopting interference coordination technology schemes. By combining CRE, adaptive ABS ratio configuration scheme can provide excellent performance improvement on a large Bias scenario. Simulation and conclusions in this paper can provide reference for the future network planning and optimization.