Terahertz broadband third harmonic mixer

Abstract

The invention provides a terahertz broadband third harmonic mixer. The terahertz broadband third harmonic mixer comprises a mixer circuit substrate, a metal cavity and a Schottky diode, wherein the mixer circuit substrate is provided with a waveguide-suspended strip line-microstrip transition structure, a grounding through hole, a suspended strip, an open-circuit line branch knot, a metal ground,an intermediate-frequency low-pass filter, an intermediate-frequency end microstrip line, a fan-shaped probe and a microstrip line, and the metal cavity comprises a radio frequency end waveguide and alocal oscillator end waveguide. The waveguide-suspended strip line-microstrip transition structure is adopted, loss caused by mismatch is reduced, the effective bandwidth is increased, the size is small, machining is easy, and the cost is low.

Description

technical field [0001] The invention belongs to the technical field of terahertz odd-order harmonic mixers, and in particular relates to a terahertz broadband third-order harmonic mixer. Background technique [0002] With the increasing demand for ultra-high-speed data transmission and high-resolution imaging, communication, radar and other application systems have higher and higher requirements for working bandwidth, and the development and utilization of terahertz wave spectrum resources have attracted much attention. In related terahertz application systems, the receiver front end must have broadband and low noise figure characteristics to ensure high sensitivity of the system. However, it is difficult to implement a low-noise amplifier in the terahertz band, so a mixer is usually used as the first stage of a terahertz receiver. [0003] Among the fundamental mixers, the local oscillator signal needs to be provided by a terahertz frequency source, which is difficult and ...

AI Technical Summary

Problems solved by technology

Due to the special structural requirements of the odd-order harmonic mixer, the balanced diode pair is usually located in the waveguide at the RF end or the local oscillator end. Due to the difficulty of matching and high processing technology requirements, the structure of the lower-frequency band odd-order harmonic mixer And the design scheme is difficult to apply to the terahertz frequency band. Currently, the terahertz frequency band usually adopts waveguide gradual change, fin line transition and other methods for impedance matching, but there are usually problems such as large size, insufficient bandwidth, and excessive loss.

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