Research On Coordinated Resource Allocation Scheme In LTE-A Heterogeneous Network

Heterogeneous network (HetNet) has changed the network topology of traditional network, which uses a mix of Macro eNodeB and low power nodes (LPNs). This new network topology not only solves the problems of signal coverage in the blind spot area and capacity enhancements in hot scenes effectively, but also improves the flexibility of network deployment and brings more convenience for using potential high band spectrum of LTE-Advanced system due to LPNs’low transmission power. However, while LPNs have improved system gains, they also have brought more complex and serious interference. Including interference between Macro eNodeB, heterogeneous network also increases the interference between Macro and LPNs and interference between LPNs and LPNs, in which interference between Macro and LPNs severely restricts system capacity of heterogeneous network.This thesis mainly studies interference and collaborative radio resource management in Macro-Pico scene of LTE-A heterogeneous network. In order to maximize the offloading benefits of Pico cells, cell range extension (CRE) technology has been proposed by 3GPP. CRE has improved the system throughput, but also made users in the CRE area of Pico cells suffer more interference from Macro eNodeB. As for this,3GPP has proposed enhanced inter-cell interference coordination (eICIC), carrier aggregation(CA) based small cells interference cancellation schemes and cooperative multipoint transmission (CoMP) technology to reduce interference of the heterogeneous network. The contributions of this paper are as follows.For the use of eICIC, CA and other enhanced ICIC technology has changed the original way of resource allocation, it is necessary to study novel resource scheduling schemes applicable to enhanced technology scenarios in heterogeneous network to improve the overall system throughput and user fairness. This paper proposes a joint dynamic scheduling algorithm of elCIC and carrier aggregation in LTE-A HetNet. Simulation results show that the proposed algorithm improves the edge user throughput and the fairness of the system. Compared to the traditional algorithm, the average edge user throughput and the system fairness index have increased by 26.5% and 35%respectively.As for advantages and disadvantages of each type of enhanced technology, there is a need to study how to adaptively choose a pattern or a combination of enhanced technology methods to enable them to adapt to the dynamic changes of heterogeneous network scenes. In this paper, resource scheduling method based on adaptive choice of enhanced technology has been proposed. The simulation evaluation shows that the proposed algorithm uses CoMP technology for the Pico base station in the first coverage and LP-ABS technology for the Pico base station in the second coverage, which brings 28.9%increase of all Pico cell average capacity. Moreover, the feature of adaptive selection according to dynamic system loads improves the flexibility and spectrum utilization.