Off-axis dual-bias Cassegrain antenna and satellite communication system comprising same

Abstract

The invention discloses an off-axis dual-bias Cassegrain antenna and a satellite communication system comprising the same, and belongs to the technical field of communication equipment. The off-axis dual-bias Cassegrain antenna comprises a fixedly arranged radiation source, a first supporting frame, a first rotary driving device which is fixedly connected with the first supporting frame, an auxiliary reflecting surface, a connecting rod, a fixed connecting sleeve, a second rotary driving device and a main reflecting surface, wherein a first rotary shaft is arranged on the first rotary drivingdevice, the auxiliary reflecting surface is connected with the first rotary shaft, one end of the connecting rod is fixedly connected with the first rotary shaft, the other end forms a free end, the fixed connecting sleeve is fixedly connected with a free end of the connecting rod in a suspended manner, the second rotary driving device is connected with the fixed connecting sleeve, a second rotaryshaft is arranged on the second rotary driving device, the main reflecting surface is connected with the second rotary shaft, when the first rotary shaft rotates, the connecting rod drives the fixedconnecting sleeve and the main reflecting surface to rotate around the central axis of the first rotary shaft, and the auxiliary reflecting surface and the main reflecting surface cooperate to achieveazimuth scanning of antenna beams. The off-axis dual-bias Cassegrain antenna is simple in structure and high in antenna beam scanning reliability.

Description

technical field [0001] The invention relates to the technical field of communication equipment, in particular to an off-axis double-biased Cassegrain antenna and a satellite communication system containing it. Background technique [0002] There are many types of reflector antennas, and they are widely used in satellite communication systems. Among them, the single-bias reflector antenna improves the sidelobe characteristics of the antenna and the return loss of the feed source, but the asymmetry of the structure will lead to the deterioration of the cross-polarization and the tilt of the circularly polarized beam; in order to overcome the single-bias Due to the inherent shortcomings of the reflector antenna, the offset double reflector antenna has been developed. For the offset double reflector antenna, the offset of the secondary reflector and the offset of the main reflector compensate each other, and both can be obtained Good side lobe and standing wave characteristics,...

AI Technical Summary

Problems solved by technology

Among them, the single-bias reflector antenna improves the sidelobe characteristics of the antenna and the return loss of the feed source, but the asymmetry of the structure will lead to the deterioration of the cross-polarization and the tilt of the circularly polarized beam; in order to overcome the single-bias Due to the inherent shortcomings of the reflector antenna, the offset double reflector antenna has been developed. For the offset double reflector antenna, the offset of the secondary reflector and the offset of the main reflector compensate each other, and both can be obtained Good side lobe and standing wave characteristics, but also good polarization characteristics

However, when the existing dual-bias reflector antenna scans the antenna, two-dimensional servos are required to realize scanning in the azimuth and pitch dimensions, and the feed source rotates with the servo, which requires additional devices such as dual-channel rotary joints. These factors will lead to The loss and weight of the feed system increase, and the structure is complex and the reliability is reduced

Images