机构地区: 华南理工大学电子与信息学院
出 处: 《华南理工大学学报(自然科学版)》 2006年第6期12-16,54,共6页
摘 要: 自适应分配技术的应用能优化多用户正交频分复用系统功率的使用.文中在对功率最优化问题进行分析后,提出了一种基于用户速率和信道特性的子载波分配算法.该算法不需要另外计算最终分配给各用户的子载波数,其分配过程包括基本分配和剩余分配两个步骤.在基本分配中保证各用户数据能被及时发送,在剩余分配过程中,以减小各用户所需的发射功率可达到最小值为原则进行子载波分配.仿真结果表明,该算法能有效降低系统的发射功率. Abstract: The application of adaptive allocation techniques to OFDM ( Orthogonal Frequency Division Muhiplexing) systems optimizes the use of system power. In this paper, a subcarrier allocation algorithm based on the required data rates of the users and the characteristics of the channels is proposed by analyzing the power optimization problem. In the proposed algorithm, the subcarrier number finally allocated to each user does not need to be calculated and the allocation process is divided into two steps, namely, the basic allocation and the residual allocation. In the basic allocation, the data of each user is transmitted in time, and in the residual allocation, the subcarriers are allocated to users according to the principle of reducing the achievable minimum transmission power required by each user. Simulated results show that the proposed algorithm can effectively reduce the transmission power.