多用户OFDM系统子载波分配算法研究

采用改进的贪婪算法分配时隙的无线资源,根据用户业务的QoS和数据队列信息确定用户的优先权,并在获知信道状态信息条件下,按照传输比特消耗功率最小原则搜索所有子载波信道,为用户动态分配子载波和比特。仿真结果表明,在两种传输速率要求下,当接入用户数相同时,改进算法比传统贪婪算法减少功率消耗3.9622W;改进算法多消耗1.9858W功率却增加了2个接入用户,用户消耗平均功率比前者少2.2456W/用户。

Improved algorithm for subcarrier allocation in multiuser OFDM system

In this paper,improved greedy algorithm was used to allocate radio resource at one slot based on limited radio resource.User’s priority was confirmed according to user’s quality of service and data queue information.Under the condition of knowing channel state information,subcarriers and bits were dynamically allocated to user according to priority,after searching all subcarrier channels on the basis of minimum transmitted power.Simulation results show that under the condition of two kinds of bit rate,when the same number of users were accessed in system,the proposed algorithm consumed power 3.9622W less than traditional greedy algorithm;the improved algorithm consumed power 1.9858W more than previous algorithm,but two more users were accessed.The average power that was consumed by users was 2.2456W/user less than former algorithm.