The Study Of Lightweight Microwave Circuit Based On 3-D Printing Technology

With the advent of the 5G era,communication technology has developed at a high speed,and communication frequencies will become higher and higher.The RF microwave circuit is the core part of the operation of the communication equipment.However,the loss of the microstrip circuit will become larger and larger with the increase of the frequency.Therefore,the advantage of the low loss microwave cavity device is revealed.However,devices made by conventional machining techniques(Such as Computerized Numerically Controlled(CNC)and EDM)are heavy.The processing costs are proportional to the structure and accuracy of the device,and they cannot process irregularly shaped devices.Since thus the weight reduction and miniaturization of the microwave circuit will be an inevitable trend,so the rapid development of 3D printing technology has enabled them to be used to manufacture high performance and low weight RF components.3D printing technology is an additive manufacturing process.The processing precision of this process can reach sub-millimeter level.For some structures with complex structure and fine size,it has great advantages over CNC technology.In the past decade,there has been a strong interest in the use of 3D printers for additive manufacturing to quickly prototype and manufacture high-geometry complexity components.3D printing additive manufacturing technology has begun to produce high performance and precision RF microwave and terahertz components.In this paper,the lightweight microwave circuit design based on 3D printing is taken as the research topic,and the Ka-band ridge gap waveguide power divider,the 3rd-order slot gap waveguide bandpass filter and the 4th-order slot gap waveguide cross-coupling bandpass filter are designed.Due to the complexity of its structure,it was fabricated by 3D printing technology and tested by professional instruments.The content arrangement of this thesis is mainly divided into five parts.The first chapter mainly introduces the importance of microwave waveguide passive components in engineering and the application of 3D printing technology in RF microwave.The second chapter explains the basic theory and analyzes methods of the gap waveguide,the basic principles of the two-port network and the three-port network,and the related characteristics and technical indicators of the waveguide power divider and the filter.The third chapter introduces the basic principles and classification of 3D printing technology,as well as the application in microwave passive waveguide devices.Meanwhile,this chapter analyzes the difficulties and limitations of current 3D printing technology in processing precision devices.The fourth chapter mainly introduces the process of designing the Ka-band ridge gap waveguide splitter,the 3rd-order slot gap waveguide bandpass filter and the 4th-order slot gap waveguide cross-coupling bandpass filter.The devices designed in this paper are optimized using Ansys HFSS and processed using 3D printing technology.The test and analysis were finally carried out in this chapter.The fifth chapter summarizes the main work of this thesis and looks to the content of the subsequent research work.