title: Stable radio-frequency phase distribution over optical fiber by phase-drift auto-cancellation.
abstract: We report a new radio-frequency (RF) phase stabilization approach for long-haul optical fiber distribution. The phase drift of an RF signal induced by fiber-length variations can be canceled out automatically via RF mixing without using active phase discrimination and dynamic phase tracking. A key significance of our approach is that no assistant local oscillator (LO) signal is needed. Consequently, frequency estimation of the received RF signal, as well as frequency locking between the LO and the received RF signal, is no longer required, which simplifies the system. A proof-of-concept experiment shows that the phase drift of the received RF signal at 9.6 GHz is significantly reduced using the proposed method. The root mean square (RMS) timing jitter is 0.76 ps when a tunable optical delay line (TODL) inserted between the remote antenna unit (RAU) and local station is changed from 0 to 300 ps.
authors: Wei
authors: W
authors: Li
authors: Wen Ting
authors: WT
authors: Wang
authors: Wen Hui
authors: WH
authors: Sun
authors: Wei Yu
authors: WY
authors: Wang
authors: Ning Hua
authors: NH
authors: Zhu