A Miniaturized Tunable Substrate Integrated Waveguide Filter

Abstract

The invention provides a miniaturized adjustable substrate integrated waveguide filter, comprising a- dielectric substrate, a waveguide unit, a signal input terminal, a signal output terminal, a grounding unit and a harmonic oscillation unit which are electrically connected;- The resonant unit is arranged on the upper surface of the dielectric substrate. The resonant unit comprises a metal layer and a resonant cavity etched on the metal layer. The side wall of the dielectric substrate is provided with a signal input terminal, a signal output terminal and a waveguide unit, wherein the signal input terminal and the signal output terminal are electrically connected with the resonant unit, and the resonant unit is connected with the grounding unit through the waveguide unit. This kind of filter has smaller size, which is advantageous for system integration and miniaturization design, and provides more flexible frequency tuning method.

Description

technical field [0001] The invention relates to the communication field, in particular to a miniaturized adjustable substrate integrated waveguide filter. Background technique [0002] With the comprehensive advancement of wireless communication technologies represented by 5G and the Internet of Things, the requirements for communication equipment are getting higher and higher. Microwave filter is one of the main units in the wireless communication system, its performance and quality play a very important role in the communication system. [0003] The commonly used microwave filters are roughly divided into lumped circuit filters, microstrip filters and substrate integrated waveguide filters. The lumped circuit filter mainly uses lumped electronic components to implement the filter circuit according to the filter principle topology to complete the filtering goal of the electromagnetic signal. The microstrip filter mainly uses the distributed parameters of the transmission ...

AI Technical Summary

Problems solved by technology

[0004] As far as the commonly used microwave filter technology is concerned, the lumped circuit filter is limited by the fact that the lumped element is no longer a simple linear element but a distributed parameter network when it works at high frequency, so there is a frequency limit in use, only Can be used for low-frequency filtering; microstrip filter, the physical size of the microstrip equivalent component structure is comparable to the wavelength, the physical size is large at low frequencies, it is difficult to miniaturize and integrate applications, and there is a large loss at high frequencies and other shortcomings; the traditional substrate-integrated waveguide filter, because the resonant frequency of the cavity mode is used to form the transmission passband, the resonant frequency of the cavity mode depends on the size of the substrate-integrated waveguide cavity, which also has large physical size and inflexible design and other shortcomings

[0005] As far as the currently commonly used tunable substrate integrated waveguide filter is concerned, the adjustable screw screw scheme is used, because the hole position of the screw screw is fixed and the grounding angle of the screw screw needs to be manually adjusted, so the tuning is not flexible and the tunable range is small and other disadvantages; the use of piezoelectric converters requires an external dedicated piezoelectric converter system and mechanical clamping and fixing structure, so there are disadvantages such as complex external implementation, high cost and large volume; using RF-MEMS or PIN diodes solution, it is necessary to build a switch circuit to control the position of the short-circuit nail in the cavity or the length of the coupling gap between the cavities, etc., the size of the filter is large, the tuning range is limited, and the price of RF-MEMS is relatively expensive, which is not conducive to large-scale application and other shortcomings

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