Resource Allocation Scheme Based On Carrier Aggregation In LTE-A System

With the continuous development of mobile Internet technology and services, the usage of mobile intelligent devices is becoming more and more popularity. Meanwhile, the demand for data rates in real-time services is increasing, and the demand for traffic in wireless networks grows exponentially, which has become a strong promotion for mobile communication technology on rapid innovation and development. On the basis of LTE technology, 3GPP has proposed LTE-Advanced technology which is the most advanced mobile communication system and has made up the shortage of the uplink peak rate and the maximum bandwidth in LTE system.Among several new technologies, carrier aggregation regarded as the core of the key technologies has become the focus of current researches.Carrier aggregation technology effectively solves the problem of scarcity of spectrum resources in mobile communication. Compared to LTE, the advantage of aggregating discrete available spectrums is to form a wider bandwidth for communication transmission so as to meet user's communication requirements.However, LTE-A system with carrier aggregation is more complex,which brings new challenges to traditional radio resource management.Considering the fairness of different user groups and the interference of cell edge, how to allocate resources more rationally is an important issue in the study of carrier aggregation resource allocation. Considering the actual situation and the backward compatibility of LTE-A system, that is,LTE-A users and LTE users can co-exist at the same time, how to choose the most reasonable carrier for different users, and also how to make full use of the channel quality and load balance of the whole system is also important research. Therefore, the main work of this paper from the following two aspects:Firstly, considering the problem of inter-layer interference and low resource utilization in the multi-cell scene of carrier aggregation,combining with the different wireless transmission characteristics of different frequency bands of the member carriers, we proposed a resource allocation algorithm that based on fractional frequency reuse to improve the original one. The algorithm takes the location of users and the interference of other cells to the user into account. As a result, the simulation results show that this scheme sacrifices a little bit of the overall performance of some users in the central area, however, the edge users and the overall performance of the system has improved considerably.Secondly, another advantage of carrier aggregation technology is backward compatibility, that is LTE-A users and LTE users can co-exist in the cell. However, LTE-A users can obtain higher system throughput through carrier aggregation technology while LTE The user can only have one carrier to its allocation of resources, so the carrier selection of members has also become a research focus. In this paper, we propose a scheme to select the member carriers with user channel conditions, load balancing and user fairness. The simulation results show that the scheme can combine Max CQI and carrier load balancing together to ensure the fairness of the system and improve the throughput.In the end, the full paper is summarized and the contribution we proposed is made clear of. Future work will be done to make deeper research in this period.