  Polarization maintenance is a key technology for free-space quantum
communication. In this paper, we describe a polarization maintenance design of
a transmitting antenna with an average polarization extinction ratio of 887 : 1
by a local test. We implemented a feasible polarization-compensation scheme for
satellite motions that has a polarization fidelity more than 0.995. Finally, we
distribute entanglement to a satellite from ground for the first time with a
violation of Bell inequality by 2.312+-0.096.
