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In this paper,we propose and experimentally demonstrate a bi-directional indoor communication system based on visible light RGB-LED.Spectrally efficient modulation formats(QAM-OFDM),advanced digital signal processing,pre- and postequalization are adopted to compensate the severe frequency response of indoor channel.In this system,we utilize red-green-blue Light emitting diodes(LEDs),of which each color can be used to carry different signals.For downlink,the low frequencies of each color are used while for uplink,the high frequencies are used.The overall data rate of downlink and uplink are 1.15-Gb/s and 300-Mb/s.The bit error ratios(BERs) for all channels after0.7 m indoor delivery are below pre-forwarderror-correction(pre-FEC) threshold of3.8×l0~(-3) To the best of our knowledge,this is the highest data rate in bi-directional visible light communication system. 相似文献
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基于副载波复用的多输入单输出正交频分复用LED可见光通信系统 总被引:1,自引:0,他引:1
提出了一种基于副载波复用的新型的多输入单输出(MISO)正交频分复用可见光通信(OFDM-VLC)系统构架,并且实验验证了2×1和3×1的MISO OFDM-VLC系统传输。分别测量了2×1和3×1的实验系统的误差矢量幅度(EVM)随输入电压变化的曲线图,找出了两个系统各自的最佳偏置范围。在将输入电压设置在最佳偏置范围之内的情况下,改变传输距离,对2×1系统,给出了系统EVM性能变化的曲线图;对3×1系统,给出了系统EVM和误码率(BER)性能变化的曲线图。在没有任何均衡的情况下,两个系统的传输距离都可以长达140cm。 相似文献
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提出了一种新型的基于串行结构的最小频移键控调制技术,产生了相位连续,频谱宽度窄,每码元时间有两次π/2相移,类似于传统最小频移键控调制信号,给出了该调制方案的理论推导,并将其应用于8进制的多维多阶调制系统中。理论和仿真分析了不同的8进制调制方案在频谱特性,残留色散容限,自相位调制容限的不同,还分析了其受到系统滤波带宽的影响。最后仿真实现了通过350km的色散完全补偿的光纤120Gb/s的数据传输。 相似文献
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We propose a configuration of a wavelength division multiplexing (WDM)-visible light communication (VLC) system using orthogonal frequency division multiplexing (OFDM) modulation and an adaptive Nyquist windowing of the OFDM signal in the receiver. Based on this configuration, we demonstrate a 750-Mb/s WDM-VLC transmission based on RGB light-emitting diode (LED) with a distance of 70 cm. The measured bit error rate (BER) for all channels are under the pre-forwaxd error correction limit of 3,8 × 10-3. The BER performances of all the channels of the proposed WDM-VLC system show considerable improvement compared with those of the system without Nvauist windowing. 相似文献