Research And Improvement On Resource Allocation Algorithm For MC-CDMA System Based On Multi-user MIMO

With the rapid development of mobile communication technology, all kinds of high speed data business, such as multimedia business, has grown rapidly, and gradually become the core business. The biggest challenge of next generation of wireless communication system is to provide users’quality of service (QoS) and efficient spectrum resource utilization. Multiple input multiple output Multi-carrier code division multiple access (MIMO-MC-CDMA) system has the advantages of diversity system, multi-carrier modulation system and the spread spectrum system such as resistance to multi-path fading, high user capacity, high data transfer rate and well reliability. So MIMO-MC-CDMA system has prospects in the next generation wireless communication. The efficiency of data transmission rate and transmission quality can be improved by resources allocation for wireless communication. Resources allocation of multi-user MIMO-MC-CDMA system is studies in this paper.Resource allocation technologies for MIMO-MC-CDMA system are studies in this paper. Adjust wireless resources such as subcarrier and power, according to each user’s channel state information; overcome the wireless channel fading by the limited wireless system resources, so as to minimize the transmitted power or maximize system channel capacity, and improve the performance of wireless communication as far as possible.First of all, MIMO-MC-CDMA system basic principle and system structure are introduced; MIMO-MC-CDMA system and multiple input multiple output orthogonal frequency division multiple access (MIMO-OFDMA) system are compared with each other; the multi-carrier system dynamic resource allocation theory and two distribution rule are analyzed in detail; several existing mainstream resource allocation schemes of MIMO-OFDMA system are stated; resource allocation algorithms are considered for maximization system throughput with total transmitted power constraint and minimization total transmitted power with given Bit Error Ratio (BER).Then, resource allocation algorithms for MIMO-MC-CDMA system are introduced, the paper analyses Lagrange multiplier algorithm and the corresponding algorithm which maximize system throughput with total transmitted power constraint. Finally, for MIMO-MC-CDMA system, combined with the different of MIMO-OFDMA system, the paper proposes a kind of resource algorithm to maximize system throughput considering the user rate proportional fairness and total transmitted power constraint. The proposed algorithm which utilizes and improves the MIMO-OFDMA system resource allocation algorithm, allocate resources for MIMO-MC-CDMA system by adaptive user grouping. First, the grouped MIMO-MC-CDMA system model is put forward, system throughput maximization and different rate requirements of users are both considered. Making use of the channel conditions, we divide the users into groups according to their average fading conditions on all subcarriers and then allocate subcarriers to the groups for which aims at maximizing total system throughput while guaranteeing proportional fairness among groups. On the foundation of theory research, the effectiveness of the proposed algorithm is verified by simulation analysis using Matlab.