Research On Cooperative Communication Technology In Heterogeneous Network

As mobile Internet gradually becomes the development trend of future network. And mobile terminals prefer to choose access the mobile communication network which has widely deployed. Rise of the mobile communication network enables the users swarm into wireless communication system to obtain data traffic. On the other hand, related studies have shown that 60% ~ 80% mobile data service scenes have changed. More and more users choose to use mobile data services indoor. And a large number of users gathering in public places will form hot zone. Based on this, LTE-Advanced system is introduced various low power nodes that used for to enhance the above scenarios by 3GPP. The new network architecture is called the heterogeneous network. But complicated network architecture of heterogeneous network will cause serious interference. At this point, the work of the mutual information coordination between nodes is an effective method for interference elimination. On the other hand, the deployment of heterogeneous network leads to the concentrated distribution of network nodes. This makes collaboration between nodes possible. In short, cooperation mechanism is of great significance for heterogeneous network, and it is an important approach to enhance network performance.This paper first introduces the LTE-Advanced system and key technologies. Then based on 3GPP LTE-Advanced systems and heterogeneous network which Macro base stations and Pico base stations are deployed, this paper proposes a resource block-level hierarchical cooperative transmission strategy for interference coordination in heterogeneous network. This cooperative transmission strategy adopts coherent transmission precoding technique, which can make multiple cooperative users are served form cooperative base station on the same resource block to reduce the cross-tier interference. In order to realize the hierarchical cooperative transmission framework, this paper proposes a cooperative resource blocks allocation strategy. In this strategy, the Macro base stations and Pico base stations commonly control the wireless resource. A heterogeneous network system level simulation platform based on LTE-Advanced is built to verify the algorithm performance of cooperative transmission technology used in this paper. And through simulating performance of LTE-Advanced heterogeneous network, we can get the results that the proposed cooperative transmission strategy is superior to the existing eICIC techniques in terms of system throughput performance.Finally, in order to adapt to wireless access network technology of 5G which require higher system capacity and spectral efficiency and according to a non-orthogonal multiple access techniques principle, we propose a heterogeneous network cooperative communication mechanism that combines NOMA to resolve the inter-layer interference problems within range expansion areas of heterogeneous network. On the basis of this heterogeneous network cooperative communication system, collaborative user scheduling and collaboration power distribution mechanism has adopted between Macro BSs and low-power BSs. After a system-level simulation, using this cooperative communication technology, we can get a significant system throughput performance gain.