多模索引调制OFDM频谱及能量效率优化方案

为提高多模索引调制正交频分复用的能量效率(energy efficiency, EE)与频谱效率(spectrum efficiency, SE),提出优化方案和相应检测算法。该方案在不减小子块间最小欧式距离的前提下通过增加模式排列的种数使系统传递的索引信息量增加,从而提升系统SE。此外该方案引入空载模式使得部分信息的传输无需消耗能量,从而提升系统EE。同时提出改进的低复杂度最大似然检测算法以降低模式排列的检测复杂度。分析模式排列数及空载模式对误比特率(bit error rate, BER)性能的影响,并据此对引入空载模式后的多模式星座进行优化。仿真结果表明,优化方案的EE和SE都有所提升,且BER性能更优。

Optimized scheme for spectrum and energy efficiency of multiple-mode OFDM with index modulation

To improve the energy efficiency (EE) and spectrum efficiency (SE) of the multiple-mode orthogonal frequency division multiplexing with index modulation, an optimization scheme and a corresponding detection algorithm are proposed. The scheme increases the number of constellation mode permutations to increase the index bit information without reducing the minimum Euclidean distance betweensub-blocks, thus enhancing the SE of the system. In addition, by using no-load mode, the scheme transmits part of the information without consuming energy, thereby improving EE. Meanwhile, an improved low complexity maximum likelihood detection algorithm is proposed to further reduce the detection complexity of mode permutations. The effect of the increased constellation permutation mode and no-load mode on the bit error rate (BER) of the system is analyzed, and the multi-mode constellation after adding no-load mode is optimized accordingly. Simulation results show that BER performance of the optimization scheme is superior, and SE is enhanced while EE gain is obtained.