Open AccessLaser-phase-fluctuation-insensitive offset-frequency-spaced two-tone optical coherent detection scheme and its transmission for radio-over-fiber systems
Author(s) -
Toshiaki Kuri,
Takahide Sakamoto,
Tetsuya Kawanishi
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.23.024140
Subject(s) - optics , frequency offset , radio over fiber , physics , offset (computer science) , optical fiber , transmission (telecommunications) , frequency deviation , radio frequency , phase noise , signal (programming language) , computer science , telecommunications , orthogonal frequency division multiplexing , channel (broadcasting) , automatic frequency control , programming language
We propose a new optical coherent detection scheme with a "two-tone" local light, which is also in principle insensitive to the laser phase fluctuation and is assisted by the digital signal processing technique for radio-over-fiber (RoF) systems. The main feature of our proposal is that the frequency separation of the two-tone local light is different from that of the RoF signal, which is called "offset-frequency-spaced" in this paper. First, we explain the principle of our new proposal and experimentally demonstrate the data recovery. Then, the influence of the frequency detuning between photo-detected modulated and unmodulated signals is discussed. Moreover, the transmission performance with an error vector magnitude (EVM) is evaluated for the optical coherent detection of a 10-Gbaud quadrature-phase-shift-keying RoF signal after a 20-km-long standard single-mode fiber transmission.