| 引用本文: | 李天云,汪峰,于翠翠.基于时频方法的工频通信系统上行信号检测[J].电力自动化设备,2008,(6): |
| .Detection of inbound signal based on time-frequency method for power frequency communication system[J].Electric Power Automation Equipment,2008,(6): |
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| 摘要: |
| 工频通信是一种以配电网为介质的新型通信技术,能否准确地检测出调制信号是该技术的关键。调制信号的检测受背景电流的影响,以往时域检测法抗干扰能力差,前、后周期做差的方法在相邻2个周期都含有调制信号时则不能检出,也就无法进行工频信号的多路传输。针对该问题,在利用三相抵消背景电流后,采用小波变换和维格纳分布(WVD)对调制信号进行检测,提出了先判断频谱后分析时频的方法,可有效地识别工频通信中的单个信号。数字仿真和实例分析证明了该方法的有效性。 |
| 关键词: 工频通信,频谱分析,小波方法,维格纳分布 |
| DOI： |
| 分类号:TN914.4 |
| 基金项目: |
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| Detection of inbound signal based on time-frequency method for power frequency communication system |
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LI Tianyun WANG Feng YU Cuicui
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| Abstract: |
| Power frequency communication takes distribution network as its medium and its key technology is the accurate detection of modulation signal,which is effected by the background current.The traditional time-domain detection method has lower anti-jamming ability.When there are modulation signals in two contiguous periods,the modulation signals could not be detected by the difference method and the multi-channel transmission of power frequency signal could not be accomplished.The method combining spectrum estimation and time-frequency analysis is proposed to effectively identify single signal in power frequency communication,which uses wavelet transform and WVD(Wigner Ville Distribution) to detect modulation signal after the background current is three-phase-counteracted.Digital simulation and example analysis have proven its effectiveness. |
| Key words: power frequency communication,spectral analysis,wavelet method,WVD |
