Parameterized Design  DDRW 


Parameterized Design  Double Ridge Rectangular Waveguide
Contents
Introduction
Abstract:A double ridge rectangular waveguide is parameterized in EMPro.A double ridge rectangular waveguide is commonly used waveguide structure for applications with higher bandwidth, low impedance, and lower cutoff frequency requirements in many microwave and antenna applications. Since different dimension or size produce a different waveguide characteristic, a parameterized 3D DDRW will make it easier for designers to characterize, optimize, and analyze the design.
Figure 1: Double Ridge Rectangular Waveguide
Design Challenges
Creating a completely parameterized 3D model in conventional EM tools is not an easy task. Sometimes it may require writing a custom code to perform specific operations such as applying constraints, or even require lots of Boolean operations. With constraints and advanced solid modeling capabilities in EMPro, it can be done easily in EMPro environment. Also ports in EMPro can be anchored to any object's vertex, edge, or faces, so that the port locations can be automatically adjusted along with the change of parameters.
In this example, a double ridge rectangular waveguide structure is shown as an example how to parameterize a 3D model with constraints such as "distance", "equal length", and "equal distance".
Figure 2 shows the dimension of DDRW and parameters.
Figure 2: Double Ridge Rectangular Waveguide Dimension and Parameters
Figure 3 shows the parameter definitions for WRD180 in EMPro parameter window.
Figure 3: WRD180 design dimensions and parameter table in EMPro
Figure 4 shows the constraints for distance, length, and equal distance.
Figure 4: Constraints menu in EMPro
Figure 5 shows the 2D sketch window with line segments applied with various constraints.
Figure 5: Constraints menu in EMPro
Results
The WRD180 double ridge rectangular wavegudie was analyzed using the FEM simulator in EMPro. The results below indicate good performance over 18GHz ~ 40GHz band.
Figure 4: S11 plot for 18~40GHz
Figure 5: S21 plot for 18~40GHz
Conclusion
With constraints and advanced solid modeling capabilities in EMPro, the double ridge rectangular waveguide can be completely parameterized, that helps designers easily characterize, optimize, and analyze the design.