Open AccessDigital linearization of multi-carrier RF link with photonic bandpass sampling
Author(s) -
Yitang Dai,
Xiaodong Liang,
Feifei Yin,
Yue Zhou,
Junyi Zhang,
Yu Li,
Jianqiang Li,
Kun Xu
Publication year - 2015
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.23.023177
Subject(s) - undersampling , band pass filter , baseband , radio frequency , electronic engineering , passband , linearization , intermodulation , physics , optics , modulation (music) , computer science , bandwidth (computing) , nonlinear system , telecommunications , acoustics , amplifier , engineering , quantum mechanics
Due to the capacity in simultaneously down-converting and receiving ultra-wideband, multi-carrier radio frequency (RF) or microwave signals, the photonic bandpass sampling has found more and more applications in multi-carrier communication, frequency-agile coherent radar, compressive sensing, etc. The nonlinear transfer during the electronics-to-optics conversion results in distortions, which are bandpass sampled and frequency-folded within the first Nyquist zone, together with the target signals. Because of the multi-octave-span operation, all nonlinearities must be considered besides the usually-concerned third-order inter-modulation distortion (IMD3). We show theoretically that a photonic bandpass sampling link is equivalent to a baseband digital nonlinear link, and then propose a corresponding linearization scheme for the output signal. Such digital linearization is capable of suppressing all types of distortions. Both numerical and experimental examples are demonstrated, where all of the 3rd-order nonlinearities, including the internal and external IMD3, the cross modulation, and 3rd-order harmonics, are well eliminated.