A Polarization Control System for Satellite Communications with Multiple Uplinks

Several groups have designed polarization control systems to solve the rain-crosspolarization problem in satellite communications. However, the multiple-uplink problem still exists, i.e., one system cannot receive signals from different uplink stations with different rain conditions simultaneously. In order to solve this problem, a new scheme is developed in this paper based on the assumption that an obtainable correlation exists between the uplink and downlink crosspolarizations and the concept that uplink and downlink can be compensated separately. The currently designed systems can be used directly in this scheme; only the addition of similar devices is necessary. The feasibility is checked by a practical example, and satisfactory performance is observed.