可见光ACO-OFDM通信系统的选择性判决反馈均衡

针对非对称限幅光正交频分复用(ACO-OFDM)的可见光通信系统中发光二极管引起的非线性失真问题,提出了一种选择性判决反馈均衡(s DFE)方法.该法设计了一个具有选择反馈均衡功能的模块,用线性信号来补偿非线性信号解决了ACO-OFDM的非线性失真,所产生的线性补偿信号可根据限幅边界范围进行选择性判决反馈,实现补偿ACO-OFDM信号频谱.仿真结果表明:在不同光功率条件下,该方法能够有效改善误码率性能,比特误码率可以达到1.37×10~(-4),恢复信号的频谱幅度可达38 d Bm.

A Selective Decision-feedback-equalization Scheme for ACO-OFDM Visible Light Communication

Aiming at nonlinearity distortion caused by light emitting diodes (LEDs) in ACO-OFDM visible light communication (VLC) system, an equalization scheme termed selective decision-feedback-equalization (sDFE) is proposed. A module with the function of selective feedback equalization is designed. The linear signal is used to compensate the nonlinear signal. And the generated linear compensation signal can be selectively judged based on the limit boundary range to compensate ACO-OFDM signal spectrum. Simulation results indicate that the sDFE method can effectively improve the bit error rate (BER) performance under different optical power conditions. The BER reaches 1.37×10^-4 and spectrum magnitude of the recovered signal is up to 38 dBm.