Research On Adaptive User Pairing And Resource Allocation Algorithm In LTE-A Uplink System Based On BER

With the emergence of new kinds of communication services, the requirements for the wireless communication system with high quality and high rate is getting higher and higher.Using the limited spectrum resource effectively, improving the efficiency of spectrum is the current research hotspot in the field of wireless communication.Multiple input multiple output technology is the key technology in the LTE-A system, it can increase the channel capacity effectively and improve the channel utilization without increasing signal transmission power and system bandwidth. However, in the uplink of LTEA, due to the limit of small volume and low battery capacity of user terminal, multi-antenna technology is hardly to realize effectively. Virtual MIMO technology can pair multiple independent user equipments which are equipped with a single antenna to reach the effect of the traditional MIMO. It solves the dilemma of multi-antenna technology effectively. User pairing algorithm which is the key technology of virtual MIMO, in the uplink of LTE-A,user pairing and resource allocation scheme directly affects the performance of the system. This paper mainly research the adaptive user pairing and resource akkocation algorithm under linear receiver in the uplink of LTE-A.Virtual MIMO fundamental in LTE-A uplink is first described in detail in this paper and some key technical characteristics of virtual MIMO is also introduced. Then virtual MIMO system model is described and the present stage research situation on the joint user pairing an resource allocation algorithm in the LTE-A plink at home and abroad is introduced. Three classical user pairing algorithms are studied and analyzed. Under linear detection, BER can be described explicitly. A threshold for the BER can be set to guarantee system performance.So system can improve the spectrum efficiency by increasing the throughput of pairing users as much as possible under specific BER threshold. Based on this idea, this paper develops BER based self-adaption joint user pairing and resource allocation algorithm in order to obtain maximum system throughput. Simulating and comparing the proposed algorithm and two present commonly used fixed 2-users pairing and resource allocation algorithms in the uplink of LTE-A, the simulation results show that the proposed algorithm can maximize the system throughput as much as possible under the BER performance guarantee. Meanwhile,different from fixed user paring and resource allocation algorithm, the proposed algorithm can realize different user pairing number and modulation order under different signal-tonoise ratio and different resources between blocks. Therefore, we can make full use of system frequency spectrum..Finally, adding system fairness considerations to the three algorithms, also simulating and comparing in the uplink of LTE-A, the simulation results show that the fairness performance of proposed algorithm is between two parties and the spectrum efficiency still has obvious advantage.