Mixer and method for suppressing output local oscillator harmonic amplitude by canceling

Abstract

A mixer and method for outputting local oscillator harmonic amplitude by canceling and suppressing, using a 0° power dividing bridge to divide the local oscillator signal from an external local oscillator source into two equal-amplitude and in-phase local oscillator signals that enter Two-way mixer, the local oscillator fundamental wave and harmonic signals output by the two-way mixer pass through a 180° coupling bridge, and the two-way local oscillator fundamental wave and harmonic signals of equal amplitude and phase are converted into two equal-amplitude and anti-phase signals , to cancel and suppress the fundamental wave and harmonic signal of the local oscillator, and focus on solving the difficulty of suppressing the fundamental wave and harmonic of the spaceborne receiver during the frequency conversion process. The use of the frequency conversion mixer of the machine and the transmitter reduces the design difficulty of the radio frequency link, improves the harmonic clutter suppression performance of the receiver, and has high safety. It can be well applied in the spaceborne communication system.

Description

technical field [0001] The invention relates to a mixer and a method for suppressing output local oscillator harmonic amplitude through cancellation, and belongs to the field of microwave technology. Background technique [0002] With the continuous development of communication satellite technology and the continuous increase of satellite communication capacity, the system has higher and higher requirements for the design of satellite-borne microwave receivers, mainly reflected in high integration, small size, and high harmonic clutter Inhibition, etc. At present, in the frequency conversion of microwave receivers in communication satellite payload transponders, the fundamental wave or harmonic of the local oscillator is very close to the frequency of the output intermediate frequency, or directly falls within the working frequency band of the intermediate frequency (such as low local oscillator, high-medium frequency Receiver frequency conversion mode), which makes it extr...

AI Technical Summary

Problems solved by technology

[0007] The technical problem solved by the present invention is: to overcome the deficiencies in the prior art, to provide a mixer and method for suppressing the output local oscillator harmonic amplitude by canceling, by adding a 0° power divider, The 180° coupling bridge and 50Ω matching load can well cancel and suppress the common local oscillator fundamental wave and harmonic signals at the output terminal of the intermediate frequency signal in the traditional mixer circuit, and focus on solving the problem of high and medium frequency and low local oscillator in the satellite-borne microwave receiver. In the frequency conversion mode, it is difficult or impossible to suppress the harmonics of the local oscillator, which greatly reduces the difficulty of designing the radio frequency link

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