Measuring Height Difference Using Two-Way Satellite Time and Frequency Transfer

According to general relativity theory (GRT), the clock at a position with lower geopotential ticks slower than an identical one higher geopotential. Here, we provide comparison using non-transportable hydrogen and transportable for altitude transmission based on two-way satellite time frequency transfer (TWSTFT) technique. First, set fifth floor another ground floor, their height difference of 22.8 m measured by tape, compared between these two clocks TWSTFT 13 days. Then, both seven days zero-baseline calibration (synchronization). Based different floors, obtained 28.0 ± 5.4 m, which coincides well tape-measured result. This experiment provides method propagation precise