Open AccessExperimental investigation on multi-dimensional digital predistortion for multi-band radio-over-fiber systems
Author(s) -
Hao Chen,
Jianqiang Li,
Kun Xu,
Yinqing Pei,
Yong Dai,
Feifei Yin,
JT Lin
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.22.004649
Subject(s) - predistortion , oversampling , radio over fiber , radio frequency , electronic engineering , computer science , power (physics) , modulation (music) , optics , physics , optical fiber , telecommunications , bandwidth (computing) , engineering , acoustics , amplifier , quantum mechanics
The recently-proposed multi-dimensional digital predistortion (DPD) technique is experimentally investigated in terms of nonlinearity order, memory length, oversampling rate, digital-to-analog conversion resolution, carrier frequency dependence and RF input power tolerance, in both directly-modulated and externally-modulated multi-band radio-over-fiber (RoF) systems. Similar characteristics of the multi-dimensional digital predistorter are identified in directly-modulated and externally-modulated RoF systems. The experimental results suggest implementing a memory-free multi-dimensional digital predistorter involving nonlinearity orders up to 5 at 2 × oversampling rate for practical multi-band RoF systems. Using the suggested parameters, the multi-dimensional DPD is able to improve the RF input power tolerance by greater than 3dB for each band in a two-band RoF system, indicating an enhancement of RF power transmitting efficiency.