本 科 毕 业 论 文（设计）
课题名称 室内低压电力线信道中噪声特性的测量与分析 学 院 专 业 班级名称 学生姓名 学 号 指导教师 完成日期
物理与电子工程学院 光信息科学与技术 光信息112班
洪杰志 1119300052 郑艳华 2015年5月25日
教 务 处 制
室内低压电力线信道中噪声特性的测量与分析
2011级光信息科学与技术(2)班 洪杰志
指导老师 郑艳华
摘要 电力线载波通信（PLC）是指利用电力线本身及其形成的输电网或配电网作
为介质实现高速数据传输的一种通信技术[1]。已取得很大的发展，但面临着严重的噪声干扰，已成为制约其发展的瓶颈，对电力线噪声测量与分析建模，将有助于对测量地区的噪声特性的了解，为利用电力线进行通信提供便利。本文主要采用AR模型对背景噪声建模和采用马尔科夫链噪声模型对脉冲噪声建模，通过对脉冲噪声提出一种基于幅值的检测和识别的方法进行脉冲噪声的提取与模型参数的确定，最后利用MATLAB软件对噪声模型进行仿真与实际功率谱对比验证。结果表明：论文中提出的建模方法是正确的。
关键词 低压电力线通信，背景噪声，脉冲噪声，AR模型，马尔科夫链脉冲模型
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Noise Measurement and Analysis of Indoor Low-voltage
Power Line Channel
ABSTRACT Power line carrier communication (PLC) refers to the use of power line
itself (and its formation of the grid or distribution network) as a communication medium to achieve data transmission technology, has achieved great development, but it is also facing serious problems of the noise interference, has become the bottleneck of restricting its development, So, The power line noise measurement and analysis and modeling is necessary, will help to understanding of the noise characteristics of measuring area, and convenient for people to build on the local power line communication model. In this paper, we adopt AR model to building background noise model and using the Markov chain model for impulse noise. In addition, put forward a method based on amplitude detection and recognition of the pulse noise to extracting and the determination of the model parameters. Finally using MATLAB simulation compared with the actual power spectrum noise model validation. The results show that the modeling method proposed in this paper is correct.
KEY WORDS Low voltage power line communication; Background noise; Impulse
noise; AR model; Markov chain model
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目录
1．绪 论 ...................................................................................................................... 1
1.1 课题研究的目的和意义 ............................................................................... 1 1.2 低压电力线信道噪声的研究现状及通信发展 ........................................... 2
1.2.1 国外电力线通信研究历程与现状 .................................................... 3 1.2.2 国内研究历程及现状 ........................................................................ 3 1.3 论文的主要研究内容及安排 ....................................................................... 4 2．低压电力线噪声测量电路的搭建 ........................................................................ 5
2.1 耦合电路设计要求 ....................................................................................... 5 2.2 电容耦合电路 ............................................................................................... 5
2.2.1 电容耦合电路图 ................................................................................ 5 2.2.2 电容耦合电路的组成及元器件选择 ................................................ 6 2.2.3 电路图仿真以及实测效果 ................................................................ 7 2.3 电感耦合电路 ............................................................................................... 9
2.3.1 电感耦合安装图 ................................................................................ 9 2.3.2 电感式耦合器的选择 ........................................................................ 9 2.3.3 电感耦合器测试效果图 .................................................................. 10 2.4 两种耦合电路的对比分析 ......................................................................... 10 3．室内低压电力线信道噪声特性研究 .................................................................. 11
3.1 噪声的分类 ................................................................................................. 11 3.2 噪声的测量 ................................................................................................. 14 3.3 噪声的特点 ................................................................................................. 17 4．室内低压电力线噪声分析建模研究与确定 ...................................................... 18
4.1 背景噪声建模研究 ..................................................................................... 18
4.1.1 背景噪声建模分析与模型的选择 .................................................. 18 4.1.2 背景噪声的AR模型以及模型参数求解 ........................................ 20 4.1.3 AR模型的定阶之FPE准则与AIC准则 .......................................... 22 4.1.4 Levinson-Durbin快速递推法 ............................................................ 24
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4.1.5 背景噪声模型参数实例计算 .......................................................... 25 4.2 脉冲噪声建模研究 ..................................................................................... 26
4.2.1 脉冲噪声建模分析与研究 .............................................................. 26 4.2.2 脉冲噪声马尔科夫链模型 .............................................................. 29 4.2.3 马尔科夫链的概率转移矩阵 .......................................................... 29 4.2.4 脉冲噪声模型概率矩阵实例计算 .................................................. 30
5．噪声模型仿真及性能分析 .................................................................................. 33
5.1 背景噪声模型仿真及实际噪声对比 ......................................................... 33 5.2 脉冲噪声模型仿真及实际噪声对比 ......................................................... 39 5.3 总结分析 ..................................................................................................... 48 6．总结与展望 .......................................................................................................... 49
6.1 总结 ............................................................................................................. 49 6.2 展望 ............................................................................................................. 49 致谢 ............................................................................................................................ 50 参考文献 .................................................................................................................... 51 附录一：专业名词英文缩写对照表 ........................................................................ 53 附录二：部分主要程序 ............................................................................................ 53
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