A relativistic frequency-transfer model that recovers differences in Earth's gravity potential from an orbiting optical atomic clock. One-way and dual-frequency microwave links between the China Space Station and ground stations are modeled to order c^-4; the dual-frequency combination cancels first-order ionospheric delay, and tropospheric delay and solid-Earth tides are corrected, so the residual gravitational frequency shift yields the gravity-potential (geoid) difference between clock sites at centimeter level for clock stability near 2x10^-15 per root-tau.
Determining differences in Earth's gravity potential from the frequency shift of signals exchanged with an orbiting optical atomic clock (chronometric/relativistic geodesy). Using dual-frequency micr…