摘要
在稀疏码多址接入(Sparse code multiple access, SCMA)系统中,码本构造和多用户检测是提升误码率(bit error rate, BER)性能的关键因素。由于用户码本间的功率不平衡可以增加远近效应,减少接收端用户间的干扰,提升多用户检测的性能,因此我们基于改善的差分进化算法,固定最小乘积距离的取值区间,以最大化最小欧氏距离为目标,构造一种同时适用于高斯信道和下行瑞利衰落信道的功率不平衡码本。仿真结果显示,所提码本与现有差分进化码本相比,在高斯信道下,当BER = 10−5时,信噪比提升了约0.3 dB;在下行瑞利衰落信道下,当BER = 10−4时,也提升了约1.0 dB。因此,所提方案构造的码本是一种性能较优的功率不平衡码本。
In sparse code multiple access systems, codebook construction and multi-user detection are key factors to improve bit error rate (BER) performance. Since the power imbalance between user codebooks can increase the near far effect, reduce the interference between users at the receiving end, and improve the performance of multi-user detection, based on the improved differential evo-lution algorithm, we fixed the value range of the minimum product distance, with the goal of max-imizing the minimum Euclidean distance, and constructed a power imbalance codebook that is ap-plicable to both the Gaussian channel and the downlink Rayleigh fading channel. The simulation results show that the SNR of the proposed codebook is improved by about 0.3 dB when BER = 10−5 in the Gaussian channel compared with the existing differential evolution codebook;In the down-link Rayleigh fading channel, when BER = 10−4, it also increases about 1.0 dB. Therefore, the code-book designed by the proposed scheme is a power imbalance codebook with better performance.
出处
《应用数学进展》
2023年第3期1207-1214,共8页
Advances in Applied Mathematics
