本文選題：小波去噪　切入點：雙譜　出處：《昆明理工大學(xué)》2016年碩士論文　論文類型：學(xué)位論文

【摘要】：國內(nèi)外的相關(guān)研究機構(gòu)對中壓電力載波的相關(guān)特性進行了細(xì)致的研究與大量的測試。中壓電力載波通信與其他通信方式有著明顯的不同,中壓線路中的分支以及配電變壓器的數(shù)量很多,不容易使用阻波器,而且實際的信道中含有著噪聲。中壓載波通信應(yīng)用較為廣泛,涉及到諸多領(lǐng)域,不過由于中壓載波電力線的載波通信信道中會出現(xiàn)信號噪聲大、干擾強、環(huán)境復(fù)雜等特點,而這些特點都會導(dǎo)致電力線載波通信的信號衰減,影響信號的穩(wěn)定性,采用何種方法解決以上問題是實現(xiàn)中壓電力載波通信技術(shù)的核心內(nèi)容。本文的主要研究內(nèi)容如下：(1)本文利用相關(guān)設(shè)備測得中壓載波信號,對試驗中測得的載波信號進行分析,利用信號處理濾出混雜的噪聲和干擾,將載波信號轉(zhuǎn)換為容易傳輸、處理、研究與辨別的形式。根據(jù)對電力載波傳輸信號狀態(tài)的研究,分析其整個過程中的諸多信息,對電力載波的現(xiàn)狀以及發(fā)展做出明確判斷。(2)針對中壓電力線通信載波中存在著的噪聲干擾問題,提出了一種小波去噪結(jié)合雙譜分析的方法。主要以采集到的中壓寬帶電力線通信信號為依據(jù),在時頻域內(nèi)對信號進行小波去噪處理,進而建立AR模型,將小波變換后的信號再進行雙譜計算。在處理信號以及提取信號特征方面,利用小波和雙譜的特點,小波去噪結(jié)合雙譜計算比傳統(tǒng)的雙譜分析方法效果更好,采用小波變換域雙譜分析方法,對中壓寬帶電力通信中通信信號提取更加明顯。(3)本文利用MATLAB進行仿真,進而得到中壓載波信號的雙譜圖,從未進行小波去噪的幾種環(huán)境下的雙譜圖可知,隨著周圍電壓的升高其雙譜圖中出現(xiàn)的波峰也逐漸加大,等高線上的能量分布也變得更加分散；小波去噪后的雙譜圖,由于主要干擾被去除,因此不同環(huán)境下的幾種信號特征在雙譜圖上較為相似,譜峰較為平穩(wěn),等高線的能量分布也較為集中。
[Abstract]:Relevant research institutions at home and abroad have carried out detailed research and a large number of tests on the related characteristics of the medium voltage power carrier. The medium voltage power carrier communication is obviously different from other communication modes. The number of branches and distribution transformers in medium voltage lines is many, it is not easy to use dampers, and the actual channel contains noise. The medium voltage carrier communication is widely used and involves many fields. However, because of the characteristics of high noise, strong interference and complex environment in the carrier communication channel of medium voltage carrier power line, these characteristics will lead to the attenuation of the signal of power line carrier communication and affect the stability of the signal. The main research content of this paper is as follows: 1) this paper uses the related equipment to measure the medium voltage carrier signal, and analyzes the carrier signal measured in the experiment. By using signal processing to filter out mixed noise and interference, the carrier signal is converted into a form of easy transmission, processing, research and discrimination. According to the study of the state of power carrier transmission signal, a lot of information in the whole process is analyzed. To make a clear judgment on the current situation and development of power carrier.) aiming at the problem of noise interference in medium voltage power line communication carrier, A method of wavelet denoising combined with bispectral analysis is proposed in this paper. The wavelet denoising processing of the signal is carried out in time-frequency domain according to the collected wideband power line communication signal, and then the AR model is established. In the aspect of signal processing and signal feature extraction, wavelet denoising combined with bispectrum calculation is more effective than traditional bispectral analysis method. Wavelet transform domain bispectrum analysis method is used to extract the communication signal more obviously in the medium voltage wideband power communication. In this paper, the MATLAB is used to simulate, and then the bispectral diagram of the medium voltage carrier signal is obtained. The bispectral images in several environments that have never been de-noised by wavelet can be seen that with the increase of the ambient voltage, the peak in the bispectrum gradually increases, and the energy distribution on the contour becomes more dispersed. Because the main interference is removed, the characteristics of several signals in different environments are similar on the bispectrum, the spectral peak is more stable, and the energy distribution of the contour is also more concentrated.
【學(xué)位授予單位】：昆明理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：TN913.6
，

本文編號：1645328