Radio frequency receiving and transmitting front end for millimeter wave holographic imaging security check system

Abstract

The invention relates to a radio frequency receiving and transmitting front end for a millimeter wave holographic imaging security check system, which comprises a millimeter wave voltage-controlled oscillator, a millimeter wave low-nose amplifier and a millimeter wave quadrature mixer, wherein the millimeter wave voltage-controlled oscillator is connected with the millimeter wave quadrature mixer; the millimeter wave low-nose amplifier is connected with the millimeter wave quadrature mixer; the millimeter wave voltage-controlled oscillator is used for generating a millimeter wave radio frequency signal to be transmitted to a target and a local oscillation signal to be fed back to the millimeter wave quadrature mixer directly; the millimeter wave low-nose amplifier is used for receiving the radio frequency signal carrying the scatter amplitude and phase information of the target to perform low-noise amplification; and the millimeter wave quadrature mixer is used for performing the quadrature mixing of the millimeter wave local oscillation signal directly fed back by the millimeter wave voltage-controlled oscillator and the radio frequency signal amplified by the millimeter wave low-nose amplifier. In the invention, after necessary preamplification and digital sampling treatment of the output signal, the millimeter wave holographic image of the target can be restored by using a millimeter wave holographic algorithm.

Description

technical field [0001] The invention relates to the fields of security inspection technology and millimeter-wave holographic imaging technology, in particular to a radio frequency transceiver front-end used in a millimeter-wave holographic imaging security inspection system. Background technique [0002] The current millimeter-wave holographic imaging security inspection system is mainly based on the years of research on millimeter-wave holographic imaging technology by scholars such as David M.Sheen and Douglas L.McMakin of the Pacific Northwest National Laboratory (PNNL), and is held by L-3 Communications in the United States. Manufactured by the company, it has been put into partial use in some sensitive airports in the United States. The millimeter-wave holographic imaging security inspection system has the technical characteristics of broadband, real-time, and three-dimensional holography. In the application of airport security inspection, it can penetrate human clothin...

AI Technical Summary

Problems solved by technology

The front-end uses an additional voltage-controlled oscillator and mixer to down-convert the RF signal to the intermediate frequency band, then performs quadrature mixing in the intermediate frequency band, and outputs I / Q signals. Therefore, the voltage-controlled oscillation used in the front-end There are more than one mixer and mixer, and the number of components is large; at the same time, the system is based on the waveguide structure, so the volume is large, the weight is heavy, the cost is high, and the product consistency is not good enough

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