Compact linear polarization tracker

Abstract

The invention discloses a compact linear polarization tracker, and relates to the technical field of satellite communication antennas. The tracker comprises an equiphase orthogonal mode coupler, a rotating orthogonal mode coupler, an L-shaped waveguide rotating joint and a stepping motor drive assembly; the L-shaped waveguide rotating joint comprises a moving waveguide with a gear arranged at one end and a waveguide with a base, and a miniature bearing cavity is machined on one corner of a mounting flange of the waveguide with the seat; the stepping motor drive assembly comprises two pinions and a transmission rod, the pinions are installed on the two sides of the miniature bearing cavity respectively through the transmission rod, one of the pinions is meshed with a drive gear, and the other one of the pinions is meshed with the gear of the moving waveguide of the L-shaped waveguide rotating joint. According to the compact linear polarization tracker, the stepping motor drive assembly drives the rotating orthogonal mode coupler to rotate around the axis of the rotating orthogonal mode coupler by 360 degrees, it is guaranteed that the electric field direction of a straight-through port of the rotating orthogonal mode coupler is matched with the electric field direction in a public port of the equiphase orthogonal mode coupler at a certain angle, and therefore the linear polarization tracking capacity is achieved.

Description

technical field [0001] The invention relates to a compact linear polarization tracker in the technical field of satellite communication antennas, in particular to a waveguide polarization tracker with compact structure for realizing passive linear polarization tracking of mobile carrier satellite communication antennas. Background technique [0002] With the development of satellite communication technology, the application of mobile carrier satellite communication antennas such as vehicle, airborne or shipborne is becoming more and more extensive. The satellite communication antenna moves with the mobile carrier all the time. Since the satellite antenna line polarization angle is fixed, in order to ensure that the satellite communication antenna line polarization transmits and receives signals, the antenna polarization angle always matches the satellite antenna’s polarization angle to avoid Because of the energy loss caused by polarization adaptation, it is required that th...

AI Technical Summary

Problems solved by technology

Active linear polarization tracking has a simple principle and short tracking time, but it can only track the linear polarization signal in the receiving frequency band, and key indicators such as system standing wave and isolation cannot be directly tested by the instrument. Passive linear polarization tracking , especially the waveguide polarization tracking device gradually replaces the active line polarization tracking and becomes the mainstream because of its universality for receiving and transmitting frequency bands, low loss, high power, and testability.

[0005] The Chinese patent application number is 201510549806.0, the name is "A New Type of Polarization Tracker", and a new type of polarization tracker is announced, which "solves the problem that the two output arms of the current polarization tracker are not parallel to the output"

However, the polarization tracker described in this invention has the following problems: 1. The working bandwidth is narrow, and the polarization tracking capability is only realized in the 14GHz~14.5GHz frequency band, and it is extended to the current broadband Ku frequency band satellite communication frequency band (receiving : 10.95GHz ~ 12.75GHz, launch: 13.75GHz ~ 14.5GHz), the standing wave, phase consistency and other performance indicators deteriorate significantly

The most deadly problem is that in practical engineering applications, even if the phase difference between the two output ports of the above-mentioned quadrature mode coupler is very good, if the phase difference between the two ports of the flat panel array antenna connected to it is large , the anti-polarization signal will also be excited in the cavity of the polarization tracker. Although the energy is very weak, if the anti-polarization signal cannot be absorbed, the impact is that in the process of polarization tracking, different frequency points The rotation angle of the polarization tracker is different, and for a certain satellite transponder antenna, the polarization angles of all frequency points in the entire working frequency band are fixed, which will greatly increase the servo system of the polarization tracker. Design difficulty and affect communication effect

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