Investigation Of The Transmission Characteristics And The Applications Of Inset Dielectric Guide

With the development of microwave technology, microwave engineering more and more focuses on the millimeter/sub-millimeter wave band. As the working frequency increases, the transmission loss caused by the skin effect and the surface roughness becomes intolerable. Meanwhile, the problems of dispersion and the high-order modes must be considered. In view of the fact that conductor loss of the rectangular waveguide increases rapidly, and the manufacturing technique can't meet the needs of the fin line and the microstrip line, the dielectric guide has been widely used to overcome these fatal defects. In particular, with merits low loss, large cross-section, and easy integration, the inset dielectric guide (IDG) is very suitable for transmitting millimeter/sub-millimeter wave.It is well known that the rapid development of modern microwave and millimeter-wave circuits requires small-size, reliable, multifunctional and low-cost system. In other word, low-cost, high-performance and high-yield microwave and millimeter-wave technologies are crucial for successfully developing the commercial broadband microwave and millimeter-wave systems at low price. As the integrated circuit appeared, the whole system can be fabricated in the same package, which reduces the volume, lowers the cost, increases the function of system, and improves the reliability of manufacture. Because of market demand, the substrate integrated technique is the hotspot in nowadays international society of microwave and millimeter-wave.This dissertation focuses on the transmission characteristics and integration applications of the IDG. The main contributions are given as follows:1. Based on equivalent circuit approach, the transmission and attenuation characteristics of the two dominant modes of IDG are schematically analyzed. Compared with some traditional transmission lines, the LSM mode IDG has merits low-loss, large cross-section, easy integration, and is very suitable for transmitting high-frequency electromagnetic wave.2. Based on artificial neural network in conjugation with numerical analysis, a method for extracting the equivalent lumped parameters of discontinuities of waveguide was proposed, which needs not to analyze field distribution and can be widely used. Furthermore, the proposed method is of much practical value for designing devices.3. We fed the LSE and LSM mode IDGs by using microstrip line and rectangular waveguide, which operate at low-frequency band and high-frequency band, respectively. In addition, we manufactured and measured microstrip-IDG transition.4. We improved the structure of traditional IDG, decreased the radiation loss of IDG, designed the inset dielectric guide bandpass filters operating at two different dominant modes, and manufactured the LSE mode filter.5. The transmission characteristics of LSE and LSM mode coupled IDGs are analyzed by the Even-Odd-Mode method. To testify the validity of the method, we manufactured and measured LSE mode IDG coupler.6. We proposed substrate integrated inset dielectric guide (SI-IDG), by using the substrate integrated technique. Moreover, we proposed the experiential equation for SI-IDG, and constructed the SI-IDG bandpass filter.