Gravitational redshift is an important prediction of General Relativity (GR). We propose a novel dual one-way frequency comparison scheme for gravitational redshift tests in satellite-ground clock experiments. Unlike conventional triple-link Doppler cancellation methods, our approach requires only two optical links, an uplink and a downlink, with Doppler data recorded independently at the satellite and ground station, respectively. Crucially, coherent combination of these measurements suppresses first-order Doppler frequency shift to second order while doubling the gravitational redshift signal. This scheme reduced engineering complexity (50% fewer links) and amplified redshift sensitivity with a factor of 2 for satellite-ground clock comparison. The scheme's viability hinges on high-precision clock synchronization (≤ 0.1 ns for 10−18 clock comparison), which is potentially achievable via state-of-the-art time-transfer techniques. Systematic error analysis confirms residual Doppler, atmospheric, and Shapiro shifts remain below 10−17 for optimized orbits, establishing this scheme as a useful tool for probing fundamental physics beyond GR.
@article{arxiv.2508.19886,
title = {A Dual One-way Doppler Cancellation Scheme for Enhanced Gravitational Redshift Tests},
author = {Cheng-Gang Qin and Tong Liu and Yang Li and Qi-Long Gong and Qin Li and Zhi-Yu Ma},
journal= {arXiv preprint arXiv:2508.19886},
year = {2025}
}