PLL-stabilized optical communications in millimeter-wave RoF systems

We demonstrate a stabilization and tuning architecture that enables the transmission of a stable modulation sideband in the presence of high carrier instability. The technique can be used in radio-over-fiber (RoF) systems employing optical intensity modulation, and in links featuring optical carrier generation, which might exhibit considerable phase noise or even frequency drift. The stabilization concept is validated experimentally in two systems based on two different laser structures. The results of this paper represent the first demonstration, to our knowledge, of the technique on a RoF system operating in the millimeter-wave range.