發(fā)布時間：2018-03-17 01:35

  本文選題：可見光通信系統(tǒng)　切入點(diǎn)：數(shù)字脈沖間隔調(diào)制　出處：《江南大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：可見光通信技術(shù)的應(yīng)用前景廣闊,但是技術(shù)復(fù)雜、成本昂貴,目前尚未大規(guī)模應(yīng)用,仍需要大量的研究。數(shù)據(jù)調(diào)制方式對可見光通信系統(tǒng)的實現(xiàn)有重要的影響,本文對目前可見光通信常用的數(shù)字脈沖間隔調(diào)制(DPIM)方式和正交頻分復(fù)用(OFDM)調(diào)制方式進(jìn)行研究。研究對比了在有保護(hù)時隙、無保護(hù)時隙、正極性調(diào)制、負(fù)極性調(diào)制多種情況下不同階數(shù)的DPIM調(diào)制的碼元結(jié)構(gòu)、平均發(fā)射功率、帶寬需求等之間的關(guān)系。研究了OFDM調(diào)制方式實現(xiàn)原理,給出了OFDM調(diào)制重要參數(shù)的選擇依據(jù)。利用發(fā)光二極管(LED)和雪崩光電二極管(APD)實現(xiàn)可見光通信系統(tǒng)是目前實現(xiàn)可見光通信的主流方案。本文分析研究了LED的調(diào)制特性用于指導(dǎo)LED驅(qū)動電路的設(shè)計。在研究APD溫度特性的基礎(chǔ)上設(shè)計了實用的APD供電電路可以保證APD增益穩(wěn)定。放大電路一般具有固定的帶寬增益積,因此窄帶通放大電路可以簡化系統(tǒng),提高信號增益,較小的帶寬也可以更好的濾除低頻電源噪聲和高頻雜波,提高信號信噪比。本文提出利用簡易元器件構(gòu)成窄帶通放大電路制作了單向可見光通信系統(tǒng)。分析研究提出一階DPIM調(diào)制方式的頻譜特性只需要比較窄的通頻帶便可以實現(xiàn)數(shù)據(jù)傳輸,適合作為該窄帶通放大電路的數(shù)據(jù)調(diào)制方式。本文采用LED發(fā)出的可見光作為數(shù)據(jù)載體,APD作為光敏器件,STC12系列單片機(jī)作為微處理器(MCU),結(jié)合DPIM調(diào)制方式和窄帶通放大電路,輔助以電源電路、下載電路、LED驅(qū)動電路等實現(xiàn)了可見光通信。實驗測試的結(jié)果表明:該系統(tǒng)可以在5m直視距離內(nèi)無聚光裝置實現(xiàn)傳輸速率約為45.8Kb/s的單向數(shù)據(jù)傳輸。系統(tǒng)穩(wěn)定性好、成本較低,具有較好的應(yīng)用前景。OFDM調(diào)制方式可以實現(xiàn)高速的可見光數(shù)據(jù)通信,是目前的研究的熱點(diǎn)。本文在單向可見光通信系統(tǒng)的設(shè)計經(jīng)驗和對相關(guān)資料的認(rèn)真研究的基礎(chǔ)上,設(shè)計了OFDM可見光通信系統(tǒng)的部分重要模塊的電路原理圖,對OFDM可見光通信系統(tǒng)的實現(xiàn)具有重要參考意義。
[Abstract]:The application of visible light communication technology has a broad prospect, but the technology is complex and expensive, so it still needs a lot of research. The data modulation mode has an important impact on the realization of visible light communication system. In this paper, the digital pulse interval modulation (DPIM) and the orthogonal frequency division multiplexing (OFDM) modulation are studied and compared with those in the protected time slot, the unprotected time slot and the positive polarity modulation in the visible light communication. The relations among symbol structure, average transmit power, bandwidth requirement of DPIM modulation with different order in many cases of negative polarity modulation are discussed. The realization principle of OFDM modulation mode is studied. The selection basis of important parameters of OFDM modulation is given. The realization of visible light communication system using LED and avalanche photodiode is the mainstream scheme to realize visible light communication at present. The modulating characteristic of LED is analyzed and studied in this paper. Performance is used to guide the design of LED drive circuit. Based on the study of APD temperature characteristics, a practical APD power supply circuit is designed to ensure the stability of APD gain. The amplifier circuit generally has a fixed bandwidth gain product. Therefore, narrowband pass amplification circuit can simplify the system, improve the signal gain, and filter the noise and clutter of the low frequency power supply better with smaller bandwidth. In this paper, a unidirectional visible light communication system is developed by using simple components to form narrowband pass amplification circuit. The spectrum characteristics of first-order DPIM modulation are analyzed and studied. Only narrow bandwidth is required for the spectrum characteristics of first-order DPIM modulation. Can achieve data transmission, It is suitable for the data modulation of the narrowband pass amplifier circuit. In this paper, the visible light emitted by LED is used as the data carrier of Guang Min device, STC12 series single chip microcomputer as microprocessor, combined with DPIM modulation mode and narrowband pass amplifier circuit. Auxiliary power supply circuit, The experiment results show that the system can transmit the unidirectional data at 45.8 KB / s within 5m direct viewing distance, and the system has good stability and low cost. OFDM modulation can realize high speed visible light data communication, which is a hot research topic at present. Based on the design experience of unidirectional visible light communication system and the study of related data, The circuit schematic diagram of some important modules of OFDM visible light communication system is designed, which has important reference significance for the realization of OFDM visible light communication system.
【學(xué)位授予單位】：江南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TN929.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 楊春勇;楊杰;陳振威;侯金;陳少平;;室內(nèi)可見光通信接收機(jī)視場角選擇與LED分布優(yōu)化[J];光電子·激光;2016年05期

2 鄭悅;田崇文;田穩(wěn);葉瑋琳;鄭傳濤;王一丁;;增益自調(diào)整型正交頻分復(fù)用可見光通信終端[J];光電子·激光;2015年08期

3 呼樹同;張建勇;張艷秋;;天線布局對于MIMO可見光通信的影響[J];光電子·激光;2015年08期

4 李洪磊;張旖旎;陳雄斌;吳春暉;郭俊清;高宗余;陳弘達(dá);;High-speed phosphorescent white LED visible light communications without utilizing a blue filter[J];Chinese Optics Letters;2015年08期

5 張俊;張劍;;可見光通信光疊加正交頻分復(fù)用技術(shù)研究[J];光電子·激光;2015年06期

6 郭倩;藍(lán)天;朱祺;倪國強(qiáng);;室內(nèi)可見光通信APD探測電路的設(shè)計與實現(xiàn)[J];紅外與激光工程;2015年02期

7 吳國秀;段發(fā)階;郭浩天;;基于TPS40210的APD偏壓溫補(bǔ)電路設(shè)計[J];電子設(shè)計工程;2015年03期

8 張良;李思敏;張文濤;李三龍;馬佳琳;;基于ADL5317和LM35的APD偏壓溫度補(bǔ)償電路設(shè)計[J];光通信技術(shù);2014年12期

9 鄧健志;程小輝;;An experimental scheme for cordwood color division multiplexing VLC system[J];Optoelectronics Letters;2014年06期

10 沈年鳳;張洪明;姚敏玉;;基于無線可見光通信的雙向語音對講系統(tǒng)[J];光電子.激光;2014年10期

，

本文編號：1622596