西安电子科技大学学报 ›› 2022, Vol. 49 ›› Issue (1): 202-207.doi: 10.19665/j.issn1001-2400.2022.01.021

• 信息与通信工程 • 上一篇    下一篇

毫米波MIMO的DNN混合预编码梯度优化方法

王勇1(),王喜媛2(),任泽洋3()   

  1. 1.西安电子科技大学 网络与信息安全学院,陕西 西安 710071
    2.西安电子科技大学 信息科学研究中心,陕西 西安 710071
    3.北京邮电大学 国际学院,北京 100876
  • 收稿日期:2021-11-29 出版日期:2022-02-20 发布日期:2022-04-27
  • 作者简介:王 勇(1978—),男,副教授,博士,E-mail: wangyong@mail.xidian.edu.cn;|王喜媛(1979—),女,讲师,博士,E-mail: xywang1@mail.xidian.edu.cn;|任泽洋(2001—),男,北京邮电大学学生,E-mail: 6268779@qq.com
  • 基金资助:
    国家重点研发计划(2018YFB0804103)

Algorithm for gradient optimization of hybrid precoding based on DNN in the millimeter wave MIMO system

WANG Yong1(),WANG Xiyuan2(),REN Zeyang3()   

  1. 1. School of Cyber Engineering,Xidian University,Xi'an 710071,China
    2. Information Science Research Center,Xidian University,Xi'an 710071,China
    3. International School,Beijing University of Posts and Telecommunications,Beijing 100876,China
  • Received:2021-11-29 Online:2022-02-20 Published:2022-04-27

摘要:

毫米波多输入多输出的混合预编码是降低硬件复杂度和能量消耗的重要方法。为降低优化处理的复杂性并提升频谱效率,提出了一种支持深度学习的混合预编码优化算法。为了消除子信道之间由信噪比差异导致部分子信道误码率较高进而对整体误码率产生的不良影响,通过基于块对角化的几何均值分解和深度神经网络的训练来选择混合预编码器,将预编码器的优化选择视为深度神经网络中的映射,以优化大规模多输入多输出的混合预编码过程。将频谱效率的优化问题近似归结为全数字预编码器和混合预编码器之间的欧氏距离的最小化问题,利用有限数量的射频链路实现吞吐量的改善。性能分析和仿真结果都表明,由于采用改进的梯度计算算法和单循环迭代结构,基于深度神经网络的方法能够最小化毫米波多输入多输出的误码率并提高频谱效率,同时显著地降低了所需的计算复杂度。当频谱效率为50 bit/(s· Hz)时,信噪比可节省3 dB。不同方案达到相同误码率时,信噪比可节省5 dB以上,并具有更好的稳健性。

关键词: 混合预编码, 频谱效率, 几何平均分解, 深度神经网络, 多输入多输出

Abstract:

Hybrid precoding of millimeter wave Multi-Input Multi-Output (MIMO) is an important method to reduce hardware complexity and energy consumption.In order to reduce the complexity of optimization processing and improve spectral efficiency,a hybrid precoding fast optimization algorithm based on deep learning is proposed.The difference in signal-to-noise ratio between subchannels may lead to a poor bit error rate performance.The hybrid precoder is selected by geometric mean decomposition (GMD) of block diagonalization and training based on the deep neural network (DNN).The optimal selection of the precoder is regarded as the mapping relationship in the DNN to optimize the hybrid precoding process of the large-scale MIMO.The optimization problem of spectral efficiency is approximately reduced to the minimization of the Euclidean distance between all digital precoders and hybrid precoders,and the throughput is improved by using a limited number of RF links.Performance analysis and simulation results show that due to the improved gradient algorithm and single cycle iterative structure,the DNN based method can minimize the bit error rate (BER) of the millimeter wave MIMO and improve the spectral efficiency,while significantly reducing the required computational complexity.When the spectral efficiency is 50bps/Hz,the SNR can be saved by 3dB.If different schemes achieve the same bit error rate,the SNR can be saved by more than 5dB and have better robustness.

Key words: hybrid precoding, spectral efficiency, geometric mean decomposition, deep neural network, multi-input multi-output

中图分类号: 

  • TP391