支撑光网络与无线网络融合的传输技术

Transmission Technology for Integration of Optical and Wireless Network

目的研究基于射频光纤传输(Radio Over Fiber,ROF)技术的通信系统传输特性及ROF技术在光与无线网络融合的接入网中的应用,为"最后一公里"的接入网提供理想的解决方案.方法分析光与无线网络融合的网络构架,对网络融合中的关键技术进行对比分析,对基于ROF技术的通信系统的传输特性进行实验研究,通过星座图观察解调的QPSK信号.结果采用单边带滤波的传输方案以及载波抑制的传输方案,经过10.36 km光纤传输之后,所得到解调信号的矢量信号误差向量幅度(Error Vector Magnitude,EVM)值为8.87%,基本保持了原始信号的性能,可有效对抗色散引入的功率衰减,实现长距离的信号传输.结论通过选择优化的传输方案,基于ROF技术的光载无线接入技术能够满足长距离传输的通信系统对于信号质量的要求.

This paper studies the transmission characteristics of communication system based on Radio over Fiber（ROF）technology,and then studies the application of ROF technology in access network for realization of optical and wireless convergence,which provides one of the most promising solutions for ′last mile′ access network.By analyzing integrated optical and wireless network architecture,the paper will discuss the key technologies involved in the network integration and focus on the investigation of transmission characteristics of the ROF technology in communication systems.Results show that the error vector magnitude（EVM）of the demodulated signal is 8.87% after 10.36 km optical fiber transmission and still remains almost as good performance as the original signal,which indicates that both the single sideband filtering transmission scheme and the carrier suppression transmission scheme used in the paper can effectively combat the influence of dispersion induced power fading and achieve long-distance transmission of the signal.With optimized transmission scheme,the optical and wireless access network based on ROF technology can realize long distance transmission of signal without influercing the signal quality.