Application of phase-stabilized optical fiber in transmission of reference and IF signals in VLBI observation

High resolution frequency standard dissemination via optical fiber metropolitan network

“…5 In radio astronomy, e.g., in the case of the Atacama Large Millimetric Array ͑ALMA͒ project or for very long base line interferometry ͑VLBI͒, the combination of high frequency and long base lines of the interferometer needs the distribution of a local oscillator with low phase noise and low phase drift through the array. 6,7 For the Deep Space Network ͑DSN͒, the Jet Propulsion Laboratory ͑JPL͒ has developed a fiber link to distribute reference signals from a H maser to synchronize each antenna of the DSN. 8,9 Modern cold atom frequency standards in the microwave domain have already demonstrated an accuracy in the 10 −15 range with the potential to reach the 10 −16 level or better.…”

Phase-coherent frequency comparison of optical clocks using a telecommunication fiber link

“…The stable synchronization afforded by the transmission of an optical carrier frequency will also foster new developments in very long baseline interferometry (VlBI) astronomy like large-aperture VlBI in the near-infrared and optical wavelength range. The combination of high frequencies and long interferometric base lines requires the distribution of a local oscillator with low phase noise and low phase drift through the array [33]. For the deep space 179 schnatz et al: comparison of optical clocks using a telecommunication fiber link Fig.…”

Cancellation of Phase Noise in 1.4 GHz RF Signal Transferred to a Remote Site through 13 km Fiber

“…(VLBI; very long baseline interferometry)을 이용한 전파 망 원경 시스템 [9][10][11][12][13] 이나 입자 물리학 실험을 위한 선형 가속기 의 동기 신호를 제공하는 데에 쓰이고 있다 [14,15] . 이러한 응 용에서는 대체적으로 1000초의 평균시간에서 10 -16 수준의 상대주파수 안정도가 요구되고 있다.…”