1. Joint Institute for Measurement Science, Tsinghua University, Beijing 100084, China;
2. State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084, China
3. Department of Physics, Tsinghua University, Beijing 100084, China;
4. National Institute of Metrology, Beijing 100029, China
Abstract:According to the requirements of the square kilometer array (SKA) for reference frequency synchronization, a fibre-based frequency synchronization scheme with the phase noise compensation function placed at the client site is demonstrated. One transmitting module hence can be linked with multiple client sites, thus forming a star-shaped topology. As a performance test, using two separate 50 km fibre spools, the 100 MHz disseminated reference frequencies at two remote sites are separately recovered. Relative frequency stabilities between two recovered frequency signals of 2.8×10-14/s and 2.5×10-17/d are obtained.
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