基于窄带频谱分析的电力线载波通信干扰过滤技术

Interference Filtering Technology of Power Line Carrier Communication Based on Narrowband Spectrum Analysis

电力线路载波通信受到背景噪声、脉冲噪声等方面干扰因素影响,导致通信信号质量下降,为此提出一种基于窄带频谱分析的通信干扰过滤技术。首先构建近似模型分析通信信号特征,利用马尔可夫链模拟信道上脉冲噪声状态。然后基于窄带频谱分析算法,在信号频谱周期图下,利用正交数据窗分离直接频谱,筛选估计方差以避免频谱泄漏事件的发生。利用傅里叶变换计算特征频谱,估计信号能量的集中特性,分析通信信号,平衡信号振幅和干扰抑制。最后通过时频峰值实施干扰滤波,有效保证电力线载波通信信号质量。经过实验数据分析证明,所提技术的载波干扰幅值最小值为1.1 dB,载波通信信号误码率平均值为1.9%,方法耗时平均值为3.8 s。

Power line carrier communication is affected by background noise,impulse noise and other aspects of interference factors,re⁃sulting in degradation of communication signal quality,for which a communication interference filtering technique based on narrowband spectrum analysis is proposed.Firstly,an approximate model is constructed to analyze the communication signal characteristics,and Markov chain is used to simulate the impulse noise state on the channel.Then based on the narrowband spectrum analysis algorithm,the direct spectrum is separated using orthogonal data windows under the signal spectrum periodogram,and the variance is screened to avoid the occurrence of spectrum leakage events.The Fourier transform is used to calculate the characteristic spectrum,estimate the concen⁃tration characteristics of the signal energy,analyze the communication signal,and balance the signal amplitude and interference suppres⁃sion.Finally,interference filtering is implemented through time⁃frequency peaks to effectively ensure the quality of power line carrier communication signals.After the experimental data analysis,it is proved that the minimum value of carrier interference amplitude of the proposed technique is 1.1 dB,the average value of carrier communication signal BER is 1.9%,and the average value of method time consumption is 3.8 s.