Research On New 3-D Print Millimeter Wave Waveguide Filter

In recent years,wireless communication has received more and more attention due to the development and application of 5G.The filters are important electronic components to wireless communication,which have been favored by more researchers.As the increase of radio frequency,finding methods of designing filters which have small size,light weight and short processing cycle has become an urgent problem to be solved.The gradual maturity of 3D printing technology has enabled researchers to find ways to solve these problems.In fact,3D printing has been increasingly invested in microwave and millimeter wave devices in recent years.Microwave millimeter wave devices based on 3D printing have appeared on the market.Taking the historical background of 3-D printing filters as an entry point,this paper focuses on the principle of filters and 3-D printing technology.In the introduction of the filter theory part,the microwave network of the filter design idea is analyzed firstly.Secondly,the comprehensive theory of the filter is expounded.Finally,the theory of Chebyshev filter and initial coupling matrix is ??explained.These introductions lay the theoretical foundation for the design of the filters in the following.In the introduction of the theoretical part of 3-D printing technology,especially the application analysis of 3-D printing technology in microwave and millimeter wave devices and the main processing technology of 3-D printing are introduced.The filter processing technique selected herein is a photo-curing(SLA)printing technique.The main work of this paper is to design three different Ka-band filters to verify this new process.Their structures are: ellipsoid structure,CQ(Cascaded Quadruplet)structure and dual mode filter.Finally,theoretical analysis of each filter,single cavity simulation and overall simulation and optimization have been carried out in this thesis.Regardless of the necessary errors caused by processing and testing,it is also in line with expectations.In addition,the processing cycle is significantly shortened and the quality is lighter.The final simulation results for the three filters are as follows: maximum return loss of is approximately 20 dB and insertion loss of is less than 0.4 dB.The test results of the ellipsoid filter: the maximum return loss is about 5dB and the insertion loss is less than 2dB.The results of the CQ structure filter: the maximum return loss is about 10 dBand the in-band insertion loss is less than 2 dB.Test results of dual-mode structure filter:maximum return loss is about 14 dB and in-band insertion loss is less than 1.6dB.