Planewave Excitation Defined as a Port

1. Workbench 4 High Frequency Electromagnetics Planewave Excitation Defined as a Port

2. Defining planewave radiation before release 9.0 • Prior to release 9.0, planewave excitation was prescribed with the PLWAVE command • Not compatible with the periodic problems that can now be set up with the CPCYC command. • No calculations of transmission and reflection coefficients were possible. • Example: planewave propagating through free space • Incoming planewave: (E = {1,0,0}V,  = 90,  = 45) as shown below. • An animation of the resulting field appears at right. z PML 45 The incoming planewave is not defined at any particular location. PLWAVE,1,0,0,90,45 PML is required on all 6 faces of the computational domain. This procedure is not compatible with periodicity and no calculations of transmission and reflection coefficients are possible. x y 90

3. Defining planewave radiation at release 9.0 • Now, at release 9.0, planewave excitation is prescribed with the HFPORT command • Compatible with the periodicity defined with the CPCYC command. • May calculate transmission and reflection coefficients with FSSPARM and HFPOWER. • Example: planewave propagating through free space • Incoming planewave: (E = {1,0,0}V,  = 90,  = 45) as shown below. • An animation of the resulting field appears at right. z PML 45 Incoming planewave is now defined as a soft port on a plane of nodes (the nodes may not be on the boundary between the computational domain and the PML). The soft port allows for calculations of reflection and transmission coefficients. HFPORT,1,PLAN,,,SOFT,1,0,0,90,45 The port sends radiation in opposite directions as shown in the animation above. y x 90

4. Example: Scattering off of a 20 X 20 array of a periodic structure • Objectives: • Read in file to automatically create model shown below • Determine variation of x component of electric field at 0.1m for  = 90, -90 <  < 0 • Calculate RF power parameters with HFPOWER. z Incoming planewave: 10GHz E = {1,0,0}V  = 90,  = 45 45 • Lossy substrate: • r = 7.5 • = 4.5e-2 Ω-m Bottom surface grounded. y x 90 PML Equivalent source flags for far field calculations. Pattern of nodes on top surface are constrained in AX (“perfectly electric conductor”) air Substrate

5. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 1: • Create model by reading in input file hf_prdc.inp. • Command line: /input,hf_prdc,inp • GUI: File=>Read input from=>choose hf_prdc.inp=>ok • Note predefined components and assemblies in the plot at right. You will apply boundary conditions and excitation on these. Apply PEC to top surface of PML mesh Soft excitation planewave and reflection coefficient extraction port Equivalent source flags to enable far field calculations. Apply PEC to bottom of substrate and conductive strip patterned on top

6. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 2: • Apply PEC conditions to components PML_A, GROUND_A, and DIPOLE_A. Note that these are area components. Consider using box selection as shown at right. 2 3 1 4

7. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 3a: • Use the component manager to select component assembly EQV_SRC. 3 1 2

8. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 3b: • Set equivalent source “flags” on component assembly EQV_SRC. This will allow calculations of far field quantities (beyond the boundaries of the modeled domain). 1 2

9. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 4: • Establish periodic boundary conditions • Select the entire model • Specify periodicity of “prd” (a predefined parameter) in the x direction as shown at right. • Repeat the procedure for the y direction. 2 3 1

10. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 5a: • Define soft interior planewave port • Use the component manager to select component PORT_A. 3 1 2

11. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 5b: • Continue defining soft interior planewave port • Define port #1 (interior port excitation on areas”) to be a planar wave source. 1 3 2 4 5

12. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 5c: • Continue defining soft interior planewave port • Define port field polarization and propagation direction as shown at right. 1 2

13. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 6: • Declare that this will be a harmonic response analysis. 2 1 3

14. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 7: • Set the frequency of the incoming wave to 10 GHz. 1 2 3

15. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 8: • Solve. 1 2

16. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 9: • Read in real part of results • Command line: set • GUI: General Postproc => Read Results => First Set • Plot electric field vectors as shown at right. 2 1 3

17. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 10a: • Plot the x component of the electric field for a 20 X 20 array of cells having x and y dimensions equal to predefined parameter “prd”. 2 3 1 4

18. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 10b: • Plot the far field for =90, with -90<<0 in 1 increments at a distance of 0.1m. 2 1 3

19. Example: Scattering off of a 20 X 20 array of a periodic structure • Step 11: • Calculate the power parameters (input and reflected power and dielectric loss). 2 3 1