导　　师： 唐友喜

学科专业： 081001

授予学位： 硕士

作　　者： ;

机构地区： 电子科技大学

摘　　要： 电力线通信/(PLC/)是利用已有的电力线网络作为信息传输媒质的一种通信方法。由于电力线网络分布广泛,因此使用电力线作为通信媒质无需在室内打孔布线重新构建通信网络,具有成本低廉、连接方便等优点,在智能家庭网络和宽带接入方面受到越来越多关注。 通信信道是通信的基础。与无线通信相同,电力线通信的性能主要受到电力线通信信道的制约。因此需要采用各种信号处理技术对抗恶劣的电力线信道对电力线通信造成的影响,提高通信性能,比如信道编解码、自适应调制解调和相干检测等,而采用这些技术的前提就是需要知道信道状态信息/(CSI/)。 正交频分复用/(OFDM/)技术具有对抗频率选择性衰落、多径时延和频谱利用率高等优点。针对电力线信道特点,可以在电力线通信中利用OFDM技术对抗电力线信道的衰减以及引入的各种噪声干扰。本论文根据电力线通信信道特点,对基于自适应OFDM调制解调的电力线通信关键技术做了研究。 本文首先介绍了课题产生的背景以及电力线通信的基本概念和发展现状,给出了本文的研究方向,最后总结了需要解决的问题。 本文对电力线通信中信号的传输媒质——电力线通信信道的特点做了一些研究。首先对电力线信道中的噪声按照特性进行分类,再根据电力线网络结构,给出电力线信道的衰落的特点,并根据电力线传输煤质的基本特性参数,采用自顶向下的建模方法建立了仿真的电力线通信信道模型。 将OFDM调制解调技术应用到电力线通信系统中,在接收端为了实现OFDM信号的相干解调,需要知道信号经历的信道信息。在本文第三部分中给出了电力线通信中基于OFDM的信道估计方法。针对电力线信道特点,本文对电力线信道估计采用了导引辅助信道估计方法估计数据处 PLC /(Power line communication/) uses the existed power line network as an information transmission media. For the wide spreading of power line network, we need not to rebuild a new communication infrastructure. For its low costing and easy connecting, it is attracting more and more attention. The communication channel is the basis for communication. As it is with the wireless communication, the performance of power line communication is also constrained by the power line channel. We have to use some complicated signal processing methods to combat with it, such as channel coding、adaptive modulation and demodulation and coherent detection and so on. All of these techniques require that the transmitter have to know the channel state information. The orthogonal frequency division multiplexing /(OFDM/) technique can combat with the frequency selective fading、multi-path delay and with higher frequency efficiency. This technique can also combat with the horrible noise in power line channel; we can use this technique to realize the high speed and reliable data transmission. This article gives a basic idea about adaptive OFDM modulation and demodulation. First we introduce the general idea of power line communication and the present researching situation of the power line communication, and then give a general idea of this thesis. In the second part, we introduce the character of the power line channel including the noise in the power line channel and the fading property of the channel. Then give a simulation channel model based on the basic parameter of the power line. In this thesis we model the power channel as a multi-path fading channel using a from top-to-bottom method. At the receiver, in order to realize the coherent demodulation, we should know the channel state information firstly. In this thesis, we use the pilot symbol assisted modulation mothed with different algorithms to estimate the channel state information. For the power line ch

关 键 词： 电力线通信 正交频分复用 电力线信道 信道估计 估计 自适应调制解调

领　　域： [电气工程]