Design of mm-RoF System Based on OFM Technique with Optimized OFDM Modulation

• 作者: 叶家骏, 宋英雄, 张林, 李迎春 林如俭, 陈翔,
• 来源期刊: 中国激光
• 年，卷（期）: 2012,（8）
• 所属期刊栏目: 光纤光学与光通信
• 页码范围: 135-142
• 页数: 8页
• 语种: 中文
• DOI: 10.3788/CJL201239.0805007

摘要

We present the design of a novel bi-directional millimeter-wave radio-over-fiber (mm-RoF) system based on the millimeter-wave generation by optical frequency multiplication (OFM).A dual-drive Mach-Zehnder modulator is used to generate high-order optical side-modes which beat in the photo-detector,producing a 40-GHz carrier.Over 100-Mb/s orthogonal frequency division multiplexing (OFDM) modulation scheme is employed.The emphasis is on developing a mathematical model for optimizing optical modulation index to the Mach-Zehnder intensity modulator (IM) for OFDM signal with high peak-to-average power ratio which imposes a limitation on the system bit error rate (BER) performance due to the non-linearity of IM.The theoretical analysis on conposite carrier to composite triple beat ratio is performed based on which extension to the system BER formula for quadrature phase shift keying/ multiple quadrature amplitude modulation (QPSK/MQAM) format is presented.The experimental proof is given in a 40-GHz RoF system at a bit rate of up to 280 Mb/s in 100-MHz bandwidth.