一种改进的基于频率选路的DWDM-ROF系统

设计了一个基于频率选路的DWDM-ROF系统。通过30 GHz射频信号驱动相位调制器,对4个间隔为100 GHz的光信道进行双边带调制,产生12个光信道。采用分插复用器将边带分成两组,一组边带分别加载2.5 Gb/s的数据,另一组不做任何变化,然后两路共同耦合进入下行光纤传输50 km,此方案最多可以解复用至6个基站分别接收毫米波信号后供天线发射,并且可以对任意信道进行选路复用。结果表明,通过4路的信道产生6路的毫米波信号,具有较高的频谱效率,同时系统信道间串扰对系统影响不大。

An Improved DWDM-ROF System Based on Frequency-Routing

A DWDM-ROF system based on frequency-routing is designed.By using a phase modulator driven by 30 GHz RF signal,the double sideband modulation is carried out on 4 optical channels separated by 100 GHz,leading to 12 optical channels.The sidebands will be divided into two groups by interleaver,one group is loaded with 2.5（Gb/s） of data respectively,the other is not changed,then these two groups are coupled into downstream optical fiber link for 50 km.This scheme can de-multiplex up to 6 base stations so as to respectively receive millimeter wave signals for transmission through antenna,and each channel can be chosen to load data.The results show that the 6 channels of millimeter wave signal generated by 4 channels of optical signal have higher spectral efficiency,while the crosstalk between channels of the system has less effect on the system.