Investigations On Microwave Circuits And Devices Based On The PCB Version Of SINRD Waveguide

With the development of informatization, microwave spectrum has become more and more crowded and millimeter wave due to its short wavelength and high bandwidth gradually gains in popularity. As a result, the nonradiative dielectric waveguide(NRD waveguide), which is the transmission line with the lowest conduct loss in very high frequency, is an attactive candidate related to the millimeter-wave technique.Starting from the basic theory of NRD waveguide, the thesis introduces a technique on fabricating the substrate integrated nonradiative dielectric(SINRD) waveguide directly on printed circuit board(PCB) or metallized dielectric layers. With the aid of 3-d electromagnetic simulation software, the paper verifies that the SINRD waveguide has the similar performance with traditional NRD waveguide. The PCB version of SINRD guides is considered to be one of the most advanced devices in low-cost and high-performance millimeter-wave hybrid integrated circuit system, because there is no need extra metal plate cover, moreover it has higher machining precision and is easy to be integrated with other planar circuits. According to the above all, the thesis proposes a new feed structure from microstrip to the PCB version of SINRD guides. The simulation and measurement results have verified the feasibility and superiority of the feeder structure.By means of the same principle of designing the NRD guide bandpass filter, the thesis has designed a novel bandpass filter of PCB version SINRD waveguide. The novel bandpass filter has a center frequency of 22.7GHz with a fractional bandwidth of 1.9%. The return loss is better than 15 dB and the insertion loss is generally smaller than 3dB in the pass band. Two kinds of 3-D electromagnetic simulation software based on different algorithm-FEM and FDTD- have been used to analyze and design the filter and the relevant results have proved the reliability of the design.