Millimeter wave array radiometer front end capable of realizing analog beamforming

Abstract

The invention relates to a millimeter wave array radiometer front end capable of realizing analog beamforming. The millimeter wave array radiometer front end comprises a radio frequency receiving circuit, a local oscillator driving phase shift circuit, an intermediate frequency combination gain adjustable circuit and a direct current power supply and digital control circuit. The radio frequency receiving circuit is arranged in an array mode and comprises eight mutually independent receiving channels, and signals are input through waveguide ports and transmitted to a millimeter wave circuit through waveguide micro-strip conversion to be amplified and mixed; a local oscillator driving signal is input through a port and is divided into eight paths in the module, and the local oscillator signal of each path passes through an analog phase shifter to realize 360-degree high-precision continuous adjustment of the phase; and intermediate frequency signals after down-conversion of each channelcan realize gain adjustment, and finally combined output is realized. The millimeter wave array radiometer front end with multiple channels, high integration level, high sensitivity, low cost and independently adjustable gain phase is realized, and the millimeter wave array radiometer front end has important practical significance for realizing real-time tracking, automatic zooming and rapid imaging of a pass-type millimeter wave human body security inspection instrument.

Description

technical field [0001] The invention relates to a front end of a millimeter wave array radiometer for passive millimeter wave imaging, which adopts multi-channel simultaneous reception, adjustable phase amplitude of each channel, combined single-port output, and is suitable for measuring electromagnetic energy radiated or reflected by objects or scenes . Background technique [0002] Millimeter-wave imaging technology has become a recognized and irreplaceable means of implementing human body security due to its harmlessness to the human body. The system can not only detect metal objects hidden under clothing, but also detect ceramic knives, Hazardous explosives such as plastic pistols, powder and liquid explosives, etc., have the advantages of long-distance detection, real-time imaging, and real-time focusing. [0003] The radiometer is a passive receiver that can receive natural radiation from objects. It detects targets by passively receiving the radiation energy of the t...

AI Technical Summary

Problems solved by technology

Although it includes four superheterodyne receiving channels, the bandwidth is narrow and the noise figure is high

In summary, the radiometer front-ends developed at home and abroad cannot meet the needs of multi-channel, high integration, high sensitivity, low cost, high-precision independent adjustable gain and phase

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