Ultra-Stable Wideband Signal Dissemination for Distributed Systems

• DOI: 10.1109/jlt.2023.3292134
• Publication Date: 2023-07-04T17:34:33Z
• Authors: Xi Wang; Wei Wei; Baixuanyao Ye; Weilin Xie; Zhongwei Tan; Yi Dong
• Keywords: Wideband; SIGNAL (programming language)

We demonstrate an ultra-stable wideband signal dissemination scheme suitable for distributed systems. By inserting a 26 GHz probe whose round-trip delay variation is precisely measured with double optical mixing, the link length has been accurately detected. Assisted well-designed homodyne phase locked loop, time stability on order of femtosecond hours and fractional frequency 8.3 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−18</sup> at 1000 s averaging time. Experimentally, tunable single-frequency ranging from 8 to 12 disseminated local end 2 remote ends via 20 km fiber links. The root-mean-square jitters are between femtoseconds within hour, indicating exceptional stability. Additionally, X-band 500 Mbps quadrature shift keying also tested as true signal. relative jitter 1.88 picoseconds, which close measurement noise floor. proposed highly desirable systems that require high strict coherence.