Ridge Waveguide Directional Coupler Design And Research

Directional coupler is a widely applied microwave component in the microwave system. It can be applied in the signal generator to surveillance the power and in the receiver to be a mixer. In addition, it can also be applied in the automatic gain controller, balance amplifier, reflection, microwave impedance bridge, and so on. Although researches in China and abroad on directional coupler has been long lasted, greatly varied and widely ranged, and it is a mature technology, less concern has been given to ridged waveguide and the reports related are rare. Compared with ridged waveguide and rectangular waveguide with the same section size, ridged waveguide has a wider single mode working bandwidth, so directional coupler which uses ridged waveguide has a wider bandwidth than that uses rectangular waveguide. So it is necessary to take a systematic research on ridged waveguide directional coupler. This dissertation values a lot not only for theory research but also for application.Based on some issues in hand, this dissertation took a deep and systematic research on ridged waveguide directional coupler. Firstly, the simple case, single-hole coupling, was discussed. In this case, the hole was set at the different position on the broad wall of the ridged waveguide. Secondly, on base of single-hole coupling, multi-hole coupling was analyzed. The methods and approaches of these cases were compared, which were equal radius distribution, binomial distribution, Chebyshev distribution, on situations that the space between the holes is equal. The bandwidth on all kinds of conditions was discussed in details. The compare and analysis of different approaches can help us to optimize the design and to get wider application.Research work of this dissertation are as follows:1. The basic theory about ridged waveguide directional coupler was deduced and consummated systematically. The sizes of ridged waveguide directional coupler with two kinds structure and formula of electromagnetic filed were obtained. All of these give us a full design theory for research of ridged waveguide directional coupler. Lots of results by this research provided the theory not only for this field but also for other correlative fields. 2. The theory analysis and numerical values computation of aperture coupling was made, and the aperture coupling was simulated in HFSS. The compared results can show that the theory is reasonable.3. In multi-hole coupling, the results were analyzed with different aperture distribution, which were equal radius distribution, binomial distribution, and Chebyshev distribution. Some useful conclusions were made out.4. The influence on directional coupler's feature parameter by its variable dimension was researched.5. The CAD and simulation program were established.