本文關(guān)鍵詞： 電力線通信 OFDM 電力線通信協(xié)議標(biāo)準(zhǔn) 信道估計(jì)技術(shù)　出處：《重慶大學(xué)》2013年碩士論文　論文類型：學(xué)位論文

【摘要】：電力線網(wǎng)絡(luò)覆蓋廣泛，接入方便，在寬帶接入和智能家庭網(wǎng)絡(luò)等應(yīng)用方面越來越受到人們的關(guān)注。正交頻分復(fù)用(OFDM)技術(shù)的抗噪聲和多徑能力強(qiáng)、頻譜利用率高，加之容易實(shí)現(xiàn)高速傳輸，因此眾多的通信協(xié)議標(biāo)準(zhǔn)都選擇OFDM技術(shù)作為數(shù)字調(diào)制技術(shù)，，在電力線載波通信中亦具有廣闊的應(yīng)用前景。 本文研究了基于OFDM的電力線載波通信信道估計(jì)算法。 首先，介紹了基于OFDM的電力線載波通信相關(guān)標(biāo)準(zhǔn)，著重研究了G3協(xié)議標(biāo)準(zhǔn)和PRIME標(biāo)準(zhǔn)，給出了兩個相關(guān)標(biāo)準(zhǔn)的系統(tǒng)框圖和詳細(xì)參數(shù)，并用Matlab仿真實(shí)現(xiàn)了兩個標(biāo)準(zhǔn)的發(fā)射信號功率譜密度。 其次，分析了基于OFDM的電力線載波通信系統(tǒng)的設(shè)計(jì)，介紹了OFDM技術(shù)的基本原理和關(guān)鍵技術(shù)，著重研究了基于OFDM的電力線載波系統(tǒng)組成的框圖，主要參數(shù)等。 再次，介紹了電力線信道下的信道估計(jì)算法：首先，詳細(xì)介紹了電力線信道的信道特性，著重研究了電力線輸入阻抗特性、噪聲特性以及衰落特性。其次，針對導(dǎo)頻的信道估計(jì)算法，指出了OFDM系統(tǒng)中非盲估計(jì)算法研究的三個要點(diǎn)：(1)發(fā)送端導(dǎo)頻的選擇與插入，討論了塊狀導(dǎo)頻、梳妝導(dǎo)頻的插入方法；(2)接收端導(dǎo)頻位置信道信息獲取的方式，詳細(xì)分析了LS(Least Squares)、MMSE(MinimumMean Square Error)、SVD(Singular Value Decomposition)這三種典型的信道估計(jì)算法的原理與特點(diǎn)。通過Matlab仿真表明：MMSE算法的性能最好，但是MMSE算法復(fù)雜度很高，難以在實(shí)際中得到應(yīng)用；SVD算法復(fù)雜度相對MMSE算法要低，但是隨著信噪比的增加，SVD算法的性能要差一些；相對來說LS算法的性能是最低的，但是LS算法簡單且易于實(shí)現(xiàn)；(3)通過導(dǎo)頻位置獲取的信道信息恢復(fù)出所有時刻信道的信息，介紹和比較了三種典型的插值算法：線性內(nèi)插、Cubic插值算法和高斯插值算法。 最后，本文根據(jù)電力線信道的特性采用了一種基于LS算法的改進(jìn)信道估計(jì)算法。通過Matlab仿真比較表明改進(jìn)后的算法運(yùn)算簡單且大大提高了LS算法的信道估計(jì)性能，在惡劣的信道環(huán)境下保證了可靠性。 本文的研究結(jié)果對電力線通信接收機(jī)的實(shí)際應(yīng)用具有一定的價值，也為今后設(shè)計(jì)完全自主知識產(chǎn)權(quán)基于OFDM電力線通信芯片奠定了基礎(chǔ)。
[Abstract]:Power line network has wide coverage and convenient access, and has attracted more and more attention in broadband access and intelligent home network applications. Orthogonal Frequency Division Multiplexing (OFDM) technology has strong anti-noise and multi-path capability. Because of the high spectrum efficiency and the high speed transmission, the OFDM technology is chosen as the digital modulation technology in many communication protocol standards, and it also has a broad application prospect in the power line carrier communication. A power line carrier channel estimation algorithm based on OFDM is studied in this paper. First of all, the paper introduces the power line carrier communication standards based on OFDM, focuses on the G3 protocol standard and PRIME standard, and gives the system block diagram and detailed parameters of the two related standards. Two standard transmit signal power spectral density are realized by Matlab simulation. Secondly, the design of power line carrier communication system based on OFDM is analyzed, and the basic principle and key technology of OFDM technology are introduced. The block diagram and main parameters of power line carrier system based on OFDM are studied. Thirdly, the channel estimation algorithm under the power line channel is introduced. Firstly, the channel characteristics of the power line channel are introduced in detail, focusing on the power line input impedance characteristics, noise characteristics and fading characteristics. Aiming at the channel estimation algorithm of pilot frequency, this paper points out three key points of the non-blind estimation algorithm of OFDM system: 1) the selection and insertion of pilot frequency at the transmitter end, and discusses the insertion method of block pilot and dressing pilot. (2) the method of obtaining the channel information of pilot position at the receiving end is analyzed in detail by LS(Least Squares). MMSE(MinimumMean Square error. SVD(Singular Value Decomposition). The principle and characteristics of these three typical channel estimation algorithms are discussed. The Matlab simulation shows that the performance of the Matlab algorithm is the best. However, the complexity of MMSE algorithm is very high, so it is difficult to be applied in practice. The complexity of SVD algorithm is lower than that of MMSE algorithm, but the performance of SVD algorithm is worse with the increase of SNR. The performance of LS algorithm is the lowest, but LS algorithm is simple and easy to implement. The channel information obtained from the pilot position is used to recover the channel information at all times. Three typical interpolation algorithms are introduced and compared: linear interpolation cubic interpolation algorithm and Gao Si interpolation algorithm. Finally. According to the characteristics of power line channel, an improved channel estimation algorithm based on LS algorithm is proposed in this paper. The results of Matlab simulation show that the improved algorithm is simple and greatly improves the channel of LS algorithm. Estimated performance. The reliability is guaranteed in the bad channel environment. The results of this paper have certain value for the practical application of power line communication receiver, and also lay a foundation for the design of independent intellectual property rights based on OFDM power line communication chip in the future.
【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2013
【分類號】：TN913.6

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 周陶濤;馬正新;王劍;山秀明;劉學(xué)信;;低壓電力線通信性能測試分析與路徑選擇[J];電工技術(shù)學(xué)報;2008年08期

2 張有兵,程時杰,何海波,熊蘭,J.Nguimbis;低壓電力線高頻載波通信信道的建模研究[J];電力系統(tǒng)自動化;2002年23期

3 湯效軍;電力線載波通信技術(shù)的發(fā)展及特點(diǎn)[J];電力系統(tǒng)通信;2003年01期

4 嚴(yán)春林;李少謙;唐友喜;羅霄;房家奕;;利用CAZAC序列的OFDM頻率同步方法[J];電子與信息學(xué)報;2006年01期

5 何世彪;張青;韓彥凈;楊迷;;OFDM同步與信道估計(jì)研究及FPGA實(shí)現(xiàn)[J];計(jì)算機(jī)工程;2013年05期

6 張繼東,鄭寶玉;基于導(dǎo)頻的OFDM信道估計(jì)及其研究進(jìn)展[J];通信學(xué)報;2003年11期

7 張杰,胡鈺;基于CAZAC序列的突發(fā)通信定時同步算法[J];無線電工程;2005年11期

8 劉海濤,張保會,譚倫農(nóng);低壓電網(wǎng)通信信道的理論分析[J];西安交通大學(xué)學(xué)報;2003年10期

9 姜霞,J.NGUIMBIS,程時杰;低壓配電網(wǎng)載波通信噪聲特性研究[J];中國電機(jī)工程學(xué)報;2000年11期

10 張保會,劉海濤,陳長德;電話、電腦、電視和電力網(wǎng)“四網(wǎng)合一”的概念與關(guān)鍵技術(shù)[J];中國電機(jī)工程學(xué)報;2001年02期

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