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According to general relativity theory (GRT), by comparing the frequenciesbetween two precise clocks at two different stations, the gravity potential(geopotential) difference between the two stations can be determined due to thegravity frequency shift effect. Here, we provide experimental results ofgeopotential difference determination based on frequency comparisons betweentwo remote hydrogen atomic clocks, with the help of common-view satellite timetransfer (CVSTT) technique. For the first time we apply the ensemble empiricalmode decomposition (EEMD) technique to the CVSTT observations for effectivelydetermining the geopotential-related signals. Based on the net frequency shiftbetween the two clocks in two different periods, the geopotential differencebetween stations of the Beijing 203 Institute Laboratory (BIL) and LuojiashanTime--Frequency Station (LTS) is determined. Comparisons show that theorthometric height (OH) of LTS determined by the clock comparison is deviatedfrom that determined by the Earth gravity model EGM2008 by (38.5$\pm$45.7)~m.The results are consistent with the frequency stabilities of the hydrogenclocks (at the level of $10^{-15}$~day$^{-1}$) used in the experiment. Usingmore precise atomic or optical clocks, the CVSTT method for geopotentialdetermination could be applied effectively and extensively in geodesy in thefuture.

Determining the gravity potential with the CVSTT technique using two hydrogen clocks