Open AccessBandpass sampling based digital coherent receiver with free-running local oscillator laser for phase-modulated radio-over-fiber links
Author(s) -
Maoyong Cao,
Jianqiang Li,
Yitang Dai,
Feifei Yin,
Kun Xu
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.027007
Subject(s) - band pass filter , phase noise , local oscillator , sampling (signal processing) , radio frequency , intermediate frequency , undersampling , optics , frequency offset , computer science , electronic engineering , laser linewidth , radio over fiber , physics , optical fiber , laser , telecommunications , engineering , channel (broadcasting) , detector , orthogonal frequency division multiplexing
A bandpass sampling based digital coherent receiver is presented for phase modulated radio-over-fiber links with coherent detection. In the scheme, the bandpass sampling technique is introduced in RoF systems to overcome the high sampling rate requirement and front-end hardware dependency of conventional digtal coherent receivers. In particular, the selection rule of bandpass sampling rate was defined by taking into account the frequency offset induced by free-running optical local oscillator. Analytical assessment and simulations are used to determine the ultimate performance in terms of tolerances to ADC bit resolution and laser linewidth. Thereafter, a 40Mbps QPSK modulated data signal at 2.4GHz RF carrier frequency is experimentally demonstrated over the proposed 50.6-km radio-over-fiber link employing bandpass sampling.