【摘要】：可見光通信(Visible Light Communication,VLC)有效解決了無線電頻譜緊缺的問題,同時(shí)具有抗電磁干擾能力強(qiáng)、保密性好、頻段無需申請(qǐng)、設(shè)備簡單以及易于安裝等優(yōu)點(diǎn)�？梢姽馔ㄐ懦藨�(yīng)用于室內(nèi)高速通信,還被廣泛應(yīng)用于汽車間通信、路燈與行人間通信等室外場景。室外可見光通信(Outdoor Visible Light Communication,OVLC)受大氣湍流、吸收等因素影響,造成光強(qiáng)隨機(jī)變化,嚴(yán)重影響系統(tǒng)的傳輸性能。本文以室外可見光通信系統(tǒng)為研究對(duì)象,圍繞抑制大氣湍流產(chǎn)生的光強(qiáng)閃爍效應(yīng)展開研究,主要研究內(nèi)容和研究成果如下:(1)將強(qiáng)度調(diào)制技術(shù)引入到室外可見光通信系統(tǒng)中,在二進(jìn)制相移鍵控子載波強(qiáng)度調(diào)制(Binary Phase Shift Keying Subcarrier Intensity Modulation,BPSK-SIM)中增加了一個(gè)直流分量,從而保證光信號(hào)強(qiáng)度幅值始終為正值;詳細(xì)推導(dǎo)了開關(guān)鍵控(On-Off Keying,OOK)強(qiáng)度調(diào)制系統(tǒng)和BPSK-SIM系統(tǒng)的誤碼率理論表達(dá)式,同時(shí)給出其它四種預(yù)調(diào)制方式下子載波強(qiáng)度調(diào)制系統(tǒng)的誤碼率理論表達(dá)式;使用Matlab工具進(jìn)行數(shù)值分析,得出BPSK-SIM系統(tǒng)能夠更有效的緩解閃爍效應(yīng)對(duì)信號(hào)強(qiáng)度的影響;然后對(duì)比分析了BPSK多子載波系統(tǒng)和單子載波系統(tǒng)誤碼性能,最后給出中斷概率對(duì)系統(tǒng)性能的影響。(2)為了能夠更好地抑制光強(qiáng)閃爍效應(yīng)對(duì)光信號(hào)傳輸?shù)挠绊?將空間分集接收技術(shù)引入到室外可見光通信系統(tǒng)中。分別推導(dǎo)了采用等增益合并(Equal Gain Combining,EGC)、最大比合并(Maximum Ratio Combing,MRC)和選擇合并(Selection Combining,SC)三種線性合并技術(shù)的BPSK-SIM系統(tǒng)的誤碼率表達(dá)式;使用Matlab工具對(duì)上述系統(tǒng)進(jìn)行信噪比、系統(tǒng)誤碼率以及大氣湍流強(qiáng)度等多維度的數(shù)值分析。結(jié)果表明采用等增益合并技術(shù)能最有效地抑制光強(qiáng)閃爍效應(yīng)。
[Abstract]:Visible light communication (Visible Light Communication,VLC (visible light communication) effectively solves the problem of the shortage of radio spectrum, and has the advantages of strong anti-electromagnetic interference ability, good confidentiality, no need to apply for frequency band, simple equipment and easy installation and so on. Visible light communication is not only used in indoor high-speed communication, but also widely used in outdoor scenes such as communication between cars, street lamps and pedestrians. Outdoor visible light communication (Outdoor Visible Light Communication,OVLC) is affected by atmospheric turbulence, absorption and other factors, resulting in random changes of light intensity, which seriously affects the transmission performance of the system. In this paper, the outdoor visible light communication system is taken as the research object, and the suppression of the light intensity flicker produced by atmospheric turbulence is studied. The main research contents and achievements are as follows: (1) the intensity modulation technology is introduced into the outdoor visible light communication system, and a DC component is added to the binary phase shift key controlled subcarrier intensity modulation (Binary Phase Shift Keying Subcarrier Intensity Modulation,BPSK-SIM). Thus, the amplitude of optical signal intensity is always positive. The theoretical expressions of BER for switching keying (On-Off Keying,OOK) intensity modulation system and BPSK-SIM system are derived in detail. At the same time, the theoretical expressions of BER for subcarrier intensity modulation systems with other four pre-modulation modes are given. Using the Matlab tool to carry on the numerical analysis, it is concluded that the BPSK-SIM system can alleviate the effect of flicker effect on the signal intensity more effectively. Then the error performance of BPSK multi-carrier system and single sub-carrier system is compared and analyzed. Finally, the effect of interrupt probability on the performance of the system is given. (2) in order to suppress the influence of light intensity flicker effect on optical signal transmission better, the performance of the system is analyzed. The spatial diversity receiving technology is introduced into the outdoor visible light communication system. The expressions of bit error rate (BER) for BPSK-SIM systems with equal gain combining (Equal Gain Combining,EGC), maximum ratio merging (Maximum Ratio Combing,MRC) and selective merge (Selection Combining,SC) are derived. The multi-dimensional numerical analysis of signal-to-noise ratio (SNR), system error rate (BER) and atmospheric turbulence intensity are carried out by using Matlab tool. The results show that the equal gain combination technique is the most effective method to suppress the flicker effect of light intensity.
【學(xué)位授予單位】：長安大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TN929.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 高俊英;王德昌;姚建國;;基于攝像頭的MIMO可見光無線通信系統(tǒng)[J];光學(xué)學(xué)報(bào);2015年01期

2 楊宇;劉博;張建昆;陳雄斌;陳弘達(dá);;一種基于大功率LED照明燈的可見光通信系統(tǒng)[J];光電子.激光;2011年06期

相關(guān)碩士學(xué)位論文 前3條

1 劉景龍;基于室外可見光LED交通燈的無線通信系統(tǒng)研究[D];哈爾濱工程大學(xué);2013年

2 高小龍;白光LED發(fā)光建模與通信系統(tǒng)研究[D];中南大學(xué);2012年

3 鄧代竹;大氣隨機(jī)信道對(duì)無線激光通信的影響[D];西南交通大學(xué);2004年

，

本文編號(hào)：2435377