We propose a novel all-optical frequency upconversion technique for radio-over-fiber (RoF) systems based on cross-gain modulation (XGM) and cross-polarization modulation (XPolM) in a semiconductor optical amplifier (SOA). A local oscillator signal is carried onto a continuous wave probe beam with orthogonally polarized single-sideband (SSB) modulation using a polarization modulator and a tunable optical filter. The intermediate frequency signal carried by a pump beam is only intensity modulated onto the sideband of the probe beam while the carrier of the probe beam is unmodulated thanks to the joint use of the XGM and XPolM effects in the SOA. This SSB upconversion scheme is inherently free from the chromatic-dispersion-induced power fading after transmission over single-mode fiber. The proposed scheme is theoretically analyzed and experimentally verified.
© 2014 Optical Society of America
Fiber Optics and Optical Communications
Original Manuscript: February 24, 2014
Revised Manuscript: March 26, 2014
Manuscript Accepted: March 27, 2014
Published: April 23, 2014
Wei Li, Wen Hui Sun, Wen Ting Wang, and Ning Hua Zhu, "All-optical frequency upconversion for radio-over-fiber applications based on cross-gain modulation and cross-polarization modulation in a semiconductor optical amplifier," Opt. Lett. 39, 2672-2675 (2014)