【摘要】 为了满足新一代无线通信系统的高数据速率、高频谱效率的通信要求 ,本文提出了基于正交频分复用(OFDM)技术的自适应调制、子载波分配及功率分配方法 ,它采用的多址方式是码分多址 (CDMA) .通过上行信道返馈获知下行信道参数 ,在一定服务质量要求 (QoS)、一定传输速率下 ,通过本文的优化分配算法 ,使系统的频谱利率最高 ,所有子载波的发射功率之和最小 .将本方法应用在下行同步信道环境下 ,系统具有较快的收敛速度 ;与非自适应OFDM比较 ,用户发射功率有较大降低 ,是一种工程可适用方案更多还原

【Abstract】 To satisfy the request of high data rate and high frequency efficiency for new generation communication system,a method of adaptive modulation modes,subcarrier and power allocation is proposed for OFDM DS/CDMA systems. With the downlink channel parameter acquired from uplink channel feedback,an optimization algorithm is utilized to maximize frequency efficiency and minimize the required transmitting power for a given QoS and data throughput.Compared with non adaptive OFDM system,the required transmitting power is greatly decreased and the convergence rate of this algorithm is very high which makes it very appropriate for engineering application.更多还原