基于OFDM可见光通信系统发送器研究  

Research on Transmitter of Visible Light Communication System Based on OFDM

作　　者：杨欣华[1] 刘洋[2] 康文炜[2] 刘斌[2] 王兆丹[3] 

机构地区：[1]吉林大学电子科学与工程学院,长春130012 [2]吉林大学通信工程学院,长春130012 [3]空军航空大学飞行教官训练基地,长春130022

出　　处：《吉林大学学报（信息科学版）》2015年第3期267-273,共7页Journal of Jilin University（Information Science Edition）

基　　金：国家自然科学基金青年基金资助项目(61201368)

摘　　要：为提高可见光通信系统的传输速率,利用OFDM(Orthogonal Frequency Division Multiplexing)调制技术,设计并实现了基于DSP(Digital Signal Process)处理器的可见光通信系统发送器。硬件系统主要由DSP电气平台、D/A(Digital/Analog)转换电路与Bias-tee/LED(Light Emitting Devices)驱动电路构成。软件系统采用16PSK调制方式对OFDM子信道进行编码,以增强系统的抗噪声能力,使之不易受信道特性变化的影响。实验结果表明,该发送器可实现OFDM数据帧发送,在调制方式为16PSK、IFFT(Inverse Fast Fourier Transform)计算为16阶基2快速傅里叶变换算法时,发送端的有效数据传输速率为18 kbit/s。负载阻值越大,发光二极管驱动电路OFDM输出信号的波形失真越小。将OFDM技术移植到可见光通信系统的研发中,不仅能提高系统的数据传输速率,同时还能有效抑制因信道衰落和延迟而引起的符号间干扰(ISI:Inter-Symbol Interference)及载波间干扰(ICI:Inter-Carrier Interference)。In order to increase the transmission rate of visible light communication system, using OFDM （Orthogonal Frequency-Division Multiplexing ） modulation techniques, a transmitter of visible light communication system is designed based on DSP processor. The hardware system includes DSP electrical platform, D/A conversion circuit and Bias-tee/LED driver circuit. The software system includes 16PSK modulation scheme to encode OFDM sub-channels, to enhance anti-noise capability of the system enhanced, ？o that it can not be affected when the Channel characteristics changed. Experimental results show that OFDM transmits data frames may be＂ implemented by the transmitter of VLC （Visible Light Communication） system based on OFDM. The effective data transfer rate of the sender is 18 kbit/s when the modulation method is 16PSK, IFFT（ Inverse Fast Fourier Transform） is calculated as 16-order radix-2 fast Fourier transform algorithm. The load resistance is greater, the waveform distortion of OFDM output signal by the LED（ Light Emitting Diode） driver circuit is less. Since the OFDM technology has been transplanted into a visible light communication system developed, the data transfer rate of the system is improved, effectively suppressing ISI （Inter-Symbol Interference） and ICI（ Inter-Carrier Interference） caused by the channel fading and delay.

关 键 词：可见光通信 正交频分复用 白光LED 

分 类 号：TN929[电子电信—通信与信息系统]