Resonant cavity special for testing decimeter wave dielectric medium capable of adding DC bias and testing method thereof

Abstract

The invention discloses a decimeter wave dielectric test special resonant cavity capable of applying a DC bias voltage and a test method. It belongs to the open-circuit coaxial line-capacitance gap resonator, and its operating frequency is 0.2-1GHz. There is a tubular insulator between the lower end cover of the coaxial cavity and the inner conductor, which forms a small-capacity ring capacitor to realize the open state of the lower end of the coaxial line; thus, DC bias can be applied to the sample. The upper end cover of the coaxial cavity and the inner conductor form an adjustable capacitance gap of 0-6mm, which can measure dielectric samples with different thicknesses, different diameters and capacitances of 1.5-13.5pF. Different coaxial cable lengths are designed and can be measured at 1 to 4 point frequencies. The resonant frequencies and the corresponding loaded Q factors of the resonant cavity with and without the sample are measured, and the complex permittivity is extracted according to the relevant formula. The system has no parasitic resonance and can measure microwave parameters of materials with a relative permittivity as high as 100 due to the inhomogeneity of the radial electric field of the sample.

Description

technical field [0001] The invention relates to a special resonant cavity for testing dielectric materials and a testing method using the resonant cavity, in particular to a special resonant cavity for testing decimeter wave dielectrics and a test method for dielectric materials in the 200-1000 MHz frequency band and capable of applying a DC bias voltage. method. technical background [0002] At the low end of the microwave frequency, it is the application frequency band of communication, radio, television, warning radar, etc. No matter on the ground or on the satellite, a large number of microwave devices such as high-power filters, dual (multi) power devices, power splitters, directional couplers, etc. made of ceramic dielectrics are needed. For example, the base station of cellular mobile communication operates in a high-power state, and only a medium with a small dielectric constant to electric field strength can produce a duplexer with a low cross-modulation distortion...

AI Technical Summary

Problems solved by technology

However, there are few reports on microwave dielectric parameter testing devices that can apply DC bias

Images