[S-GD01] [EE] Geodetic Technologies, Networks and Strategies for Global Geodetic Observing System (GGOS)

[SGD01-P10] On-site Frequency Measurements of a Rubidium Oscillator for Gravimeters

*Kazuma Mochizuki^1,3, Kazunari Nawa¹, Tomonari Suzuyama² (1.GSJ, AIST, 2.NMIJ, AIST, 3.Shizuoka Univ.)

It is important for precise gravity measurement to calibrate the frequency of a rubidium oscillator as a time frequency standard. We demonstrate simple on-site frequency measurement by using a time frequency calibration tool (FT-001A) with a GPS common view method. We equipped one at F-net IGK station, Ishigaki, Japan and measured frequency variation of the internal rubidium oscillator of gPhone gravimeter (S/N 133). As a result, we could measure its frequency with uncertainty of approximately 10^-12 (0.01 mHz) on the gravity station 2,000 km apart from AIST Tsukuba where UTC(NMIJ) is maintained.