  Light wave-packets propagating from the Earth to satellites will be deformed
by the curved background spacetime of the Earth, thus influencing the quantum
state of light. We show that Gaussian coherence of photon pairs, which are
initially prepared in a two-mode squeezed state, is affected by the curved
spacetime background of the Earth. We demonstrate that quantum coherence of the
state increases for a specific range of height h and then gradually approaches
a finite value with further increasing height of the satellite's orbit in Kerr
spacetime, because special relativistic effect are involved. Meanwhile, we find
that Gaussian coherence increases with the increase of Gaussian bandwidth
parameter, but the Gaussian coherence decreases with the growth of the peak
frequency. In addition, we also find that total gravitational frequency shift
causes changes of Gaussian coherence less than $%1$ and different initial peak
frequencies also can effect rate of change with the satellite height in
geostationary Earth orbits.
