计算机工程 ›› 2018, Vol. 44 ›› Issue (6): 57-61.doi: 10.19678/j.issn.1000-3428.0046907

• 移动互联与通信技术 • 上一篇    下一篇

基于OFDM的子载波加权技术研究

薛梅 1,周杰 1,邵根富 2   

  1. 1.南京信息工程大学 电子与信息工程学院,南京 210044; 2.杭州电子科技大学 自动化学院,杭州 310000
  • 收稿日期:2017-04-21 出版日期:2018-06-15 发布日期:2018-06-15
  • 作者简介:薛梅(1994—),女,硕士研究生,主研方向为OFDM通信理论;周杰,教授、博士生导师;邵根富,教授级高级工程师。
  • 基金项目:

    国家自然科学基金面上项目(61471153);江苏省高校自然科学基金重大项目(14KJA510001)。

Research on Subcarrier Weighting Technology Based on OFDM

XUE Mei  1,ZHOU Jie  1,SHAO Genfu  2   

  1. 1.School of Electronic and Information Engineering,Nanjing University of Information Science and Technology,Nanjing 210044,China; 2.School of Automatization,Hangzhou Dianzi University,Hangzhou 310000,China
  • Received:2017-04-21 Online:2018-06-15 Published:2018-06-15

摘要:

针对正交频分复用(OFDM)系统中固有的高旁瓣问题,结合子载波加权方法,提出一种OFDM系统旁瓣抑制算法。根据若干优化限制进行优化运算,使得传输信号的旁瓣达到最小值,从而确定载波权重。在子载波加权的基础上引入时域加窗,将发射信号与不同于传统矩形窗的窗函数做相乘运算,最终对带外辐射进行有效抑制。仿真结果表明,在无需传输任何边信息的情况下,子载波加权方法平均能够抑制辐射强度不低于10 dB的OFDM旁瓣,对加权后的OFDM信号采取加窗处理,则可以抑制辐射强度约为25 dB的旁瓣。

关键词: 正交频分复用, 带外辐射, 旁瓣抑制, 子载波加权, 优化限制, 加窗

Abstract:

Based on the inherent high sidelobe problem in Orthogonal Frequency-Devision Multiplexing (OFDM) system,a sidelobe suppression method for OFDM system is proposed based on subcarrier weighting method.The subcarrier weights are determined in such a way that the sidelobes of the transmission signal are minimized according to an optimization algorithm which allows several optimization constraints.To more effectively suppress the out-of-band radiation,the time domain windowing is introduced on the basis of the subcarrier weighting.The emission signal is multiplied by a window function which is different from the conventional rectangular window.Simulation results show that,the subcarrier weighting method can suppress the radiation intensity on average not less than 10 dB of OFDM sidelobe in the average without requiring the transmission of any side information,after the weighted transmission signal is windowed,the suppression effect of the sidelobe of the OFDM signal can reach about 25 dB.

Key words: Orthogonal Frequency-Devision Multiplexing(OFDM), out-of-band radiation, sidelobe suppression, subcarrier weighting, optimization constraints, windowing

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