Monolithic integration technology based terahertz frequency mixing circuit

Abstract

The invention discloses a monolithic integration technology based terahertz frequency mixing circuit. The monolithic integration technology based terahertz frequency mixing circuit comprises a radio frequency 3dB branch waveguide directional coupler, a local oscillation 135-degree phase shift 3dB branch waveguide directional coupler, a coaxial probe, an intermediate coupling ring, an intermediate frequency signal and two terahertz sub-harmonic mixers; each terahertz sub-harmonic mixer comprises radio frequency waveguide-microstrip transition, a monolithic integration Schottky diode pair, a local oscillation waveguide-microstrip transition, an intermediate frequency filter and a local oscillation low-pass filter; and the monolithic integration Schottky diode pair is a diode pair in inverse parallel connection. The harmonic mixers in the erahertz frequency mixing circuit are obtained by adopting a semiconductor technology; the position of diodes and the size of a micro-strip circuit can be controlled precisely; the error is far less than that of manual configuration; the influence from the configuration error to the performance of the frequency mixing circuit is reduced greatly; meanwhile, the frequency mixing circuit can remove local oscillation noise efficiently and improves the noise performance and the efficiency of a system.

Description

technical field [0001] The invention relates to a terahertz frequency mixing circuit based on monolithic integration technology. Background technique [0002] Terahertz (THz) waves refer to electromagnetic waves with frequencies in the range of 0.1 THz to 10 THz (wavelengths of 0.03 mm to 3 mm). It is an important member of the electromagnetic spectrum family, between infrared light waves and microwaves, the long wave band coincides with millimeter waves and submillimeter waves, and the short wave band coincides with infrared light. Its basic theory, research methods and technologies are also related to microwave, The two disciplines of light and wave are connected and compatible with each other. It is a comprehensive discipline formed by the rapid development at the end of the last century and the beginning of this century. The unique location of terahertz waves in the electromagnetic spectrum makes it transient, broadband, coherent, and low-energy, and it has important re...

AI Technical Summary

Problems solved by technology

However, there is no solution to eliminate the noise introduced by the local oscillator port in the current terahertz radiometer front end

On the other hand, due to the limitation of processing conditions, the existing receiver circuit usually adopts multi-level circuit arrangement when there are multiple input and output ports. The overall circuit requires multiple substrates and cavities, and requires Connect waveguide or probe, complex processing, high cost, large transmission loss

In addition, as the core of the nonlinear effect of the mixer, the performance and assembly of the diode directly affect the performance of the mixer. When processing and assembling in the low frequency band, the circuit size is relatively large, and the "flip-chip" method is often used to use conductive glue to The diode is attached upside down on the microstrip of the circuit, but when it rises to the terahertz frequency band, the size of the circuit decreases sharply, and the manual assembly method can no longer ensure its accuracy

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