改进型ACO-OFDM调制系统及其FPGA实现

Visible Light Radio Frequency Identification Tag System Based on Improved ACO-OFDM Modulation

非对称削波光正交频分复用(ACO-OFDM)是一种适用于光通信的高效数字调制解调系统.传统具有高速傅里叶变换模块(FFT)的ACO-OFDM系统,由于FFT模块的架构与系统本身不完全匹配,造成了硬件资源的大量占用与频谱资源的浪费.为了解决这个问题,完成了基2标准时延结构流水线型FFT处理器的设计验证,在150 MHz的系统时钟下,输出延迟为990 ns,功能表现良好.并通过加入载波同步单元,降低了约60%误码率.仿真结果表明,该方法提高了ACO-OFDM系统的通信性能.

Asymmetric clipped optical orthogonal frequency division multiplexing(ACO-OFDM)is an efficient digital modulation and demodulation system for optical communications.The traditional ACOOFDM system with a fast Fourier transform module(FFT),because the architecture of the FFT module does not completely match the system itself,causes a large occupation of hardware resources and waste of spectrum resources.In order to solve this problem,a new non-uniform limiting optical orthogonal frequency division multiplexing(ACO-OFDM)system is proposed.The bit error rate is reduced about 60%by adding a carrier synchronization unit and the stability of the system is improved.Under 150 MHz system clock,the output delay is 990 ns.Simulation results show that the proposed method improves the communication performance of the ACO-OFDM system.