Gravitational Redshift Test Using Rb Clocks Of Eccentric GPS Satellites

Abstract

This letter reports a new test of gravitational redshift, which is a consequence of the Einstein equivalence principle, using Rb clocks located on GPS Block IIF satellites. The fractional deviation of the gravitational redshift was measured using 11,144 days' data from Rb clocks from five GPS Block IIF satellites. The systematic effects related to orbital uncertainty, temperature, and magnetic field were conservatively modeled. The fractional deviation of the gravitational redshift from the general relativity prediction was measured with (-21.29 ± 3.95) x 10-5 at one sigma.