一种基于灌水原理的多载波CDMA系统子信道分配方案

多载波CDMA因具有带宽利用率高、抗多径衰落性能强和适合高速数据传输等优点而受到广泛关注.本文提出了一种可用于前向链路自适应子信道分配的多载波CDMA系统模型.在该模型中,用户首先估计前向链路中各子信道的衰落幅度,并将所有衰落可接受的子信道的序号反馈给基站.根据反馈的信息,提出了类似于灌水原理的子信道分配方案.理论分析和仿真结果表明:对于随机特征码情况,该方案的整体性能优良.

A Subchannel Allocation Scheme Based on the Water-Filling Principle for Multicarrier CDMA System

Recently,multicarrier(MC) transmission schemes have been introduced into CDMA (Code division multiple access) systems to get such advantages as bandwidth efficiency,resistance to multipath fading and high data rate transmission etc.In this paper,a new model of MC/CDMA system is proposed for forward links transmission.In the proposed systems,the user estimates all subchannels' fading amplitudes and feeds back all indices of its interested subchannels (whose fading amplitude can be accepted) to the basestation,Based on the indices information,we propose a new subchannel allocated method similar to the water filling (WF) principle.Theoretical and simulation results show that the average performance in the proposed system can be improved compared with that only using the favorite subchannel for each user,given the condition that the random signature sequences are used.