Research Of Interference Coordination In LTE-Advanced Heterogeneous Networks

As the evolution of LTE, LTE-A is developed to fulfill the requirement of low transmission delay and higher transmission rate. Considering that mobile internet services have some distinctive characteristics, such as higher indoor traffic, Hotspot effect, low velocity movement and higher data rate, 3GPP proposes the solution of LTE-A Heterogeneous Networks with the introduction of HeNB. This paper mainly studies of the interference coordination algorithm aiming to solve the downlink interference caused by the co-channel deployment of MeNB and HeNB.According to the investigation of domestic and foreign research, this paper firstly compares the FFR-HetNets, FFR3-HetNets and FFR6-HetNets algorithm aiming to solve the MeNB-HeNB cross-layer interference. Then, the FFR algorithm using to solve the HeNB-He NB co-tier interference is simulated.Based on the HeNB-HeNB co-tier downlink interference scenario, this paper improves the FFR algorithm, proposing a weight-based CR-ICIC algorithm. Using cognitive radio technology, this paper designs a new division and application scheme of the spectrum. Besides, a new spectrum allocation method is proposed. Simulation result shows that the weight-based CR-ICIC algorithm performs much better than FFR algorithm in many key indicators, such as overall cell-edge throughput, spectral efficiency and user fairness.Based on the MeNB-HeNB cross-tier downlink interference scenario, this paper proposed a time domain ICIC algorithm with an objective function. Considering the real-time user fairness and paid priority of HeNB, this paper improves the Jain Fairness Index to build the objective function, as a result of dynamically optimizing the ABS configuration. Simulation result shows the time domain ICIC can improve the SINR of the victim MUE. Besides, the ABS configuration can be optimized according to different paid priority of the HeNB, maintaining both the high throughput of MUE and user fairness.