1. MWO – APPLICATION IN FILTER DESIGN Soh Ping Jack Sabarina Ismail

2. 2 1.0FILTER DESIGN PROCESS Filter Specification Low-pass Prototype Design Scaling & Conversion Filter Implementation Optimization & Tuning Done using MWO

3. 3 1.1FILTER DESIGN PROCESS Filter Specification Low-pass Prototype Design

4. 4 1.2GENERAL STEPS IN FILTER DESIGN A. Know your filter specifications 1. Max Flat/Equal Ripple, 2. LPF/HPF/BPF/BSF 3. Desired freq of operation 4. Passband & stopband range 5. Max allowed attenuation (for Equal Ripple) B. Design your LPF Prototype 1. Min Insertion Loss level, No of Filter Order/Elements 2. Determine whether shunt cap model or series inductance model to use 3. Determine elements’ values from Prototype Table

5. 5 1.3FILTER DESIGN PROCESS Scaling & Conversion

6. 6 1.4GENERAL STEPS IN FILTER DESIGN C. Scaling & Conversion 1. Draw LPF filter prototype 2. Determine if there are any conversion to HPF/BPF/BSF required 3. If yes, convert the LPF to the desired HPF/BPF/BSF filter prototype. If no, move on to step 4. 4. Use equations to de-normalize cap & inductance values 5. Re-draw de-normalized filter prototype

7. 7 1.5FILTER DESIGN PROCESS Filter Implementation Optimization & Tuning Done using MWO

8. 8 1.4GENERAL STEPS IN FILTER DESIGN D. Filter Implementation & Optimization 1. Draw de-normalized LPF filter prototype with elements’ values 2. Implement filter prototype on software 3. Optimize & tune filter to get best response To do this you have to be familiar with MWO

9. 9 2.0KNOW YOUR SOFTWARE - BASIC 2.1Working in the Circuit Schematic Environment 2.2Selecting & placing elements 2.3Setting project frequency range 2.4Changing elements’ values 2.5Adding result Graphs & Charts

10. 10 2.0KNOW YOUR SOFTWARE - BASIC

11. 11 2.0KNOW YOUR SOFTWARE - BASIC 2.1Working in the Circuit Schematic Environment To add a new Schematic, right- click on “Circuit Schematic” icon and select “New Schematic”

12. 12 2.0KNOW YOUR SOFTWARE - BASIC 2.1Working in the Circuit Schematic Environment A pop-up window like this will appear after clicking “New Schematic”, click on “OK” button after entering the desired name

13. 13 2.0KNOW YOUR SOFTWARE - BASIC 2.1Working in the Circuit Schematic Environment A blank schematic like this will appear. It is used for the placement of components/elements

14. 14 2.0KNOW YOUR SOFTWARE - BASIC

15. 15 2.0KNOW YOUR SOFTWARE - BASIC 2.2Selecting and Placing Elements To select a specific element, ensure that the “Elem” tab is selected. Elements are sorted into categories as shown in the box above

16. 16 2.0KNOW YOUR SOFTWARE - BASIC 2.2Selecting and Placing Elements For example, to select a capacitor, select “Capacitor” categories on the top box. A specific capacitor then can be selected from the box at the bottom

17. 17 2.0KNOW YOUR SOFTWARE - BASIC 2.2Selecting and Placing Elements To insert the desired element into the schematic, click on the specific element in the bottom box and drag till an outline of the element appear as shown. Click again to place the element

18. 18 2.0KNOW YOUR SOFTWARE - BASIC

19. 19 2.0KNOW YOUR SOFTWARE - BASIC 2.3Setting project frequency range To edit simulation freq sweep/range, double-click on the “Project Options” icon

20. 20 2.0KNOW YOUR SOFTWARE - BASIC 2.3Setting project frequency range Define desired “Start Freq”, “Stop Freq” & “Freq Step”. It should not be too refined in an initial simulation List of the simulated freq points will be listed down when “Apply” button is clicked

21. 21 2.0KNOW YOUR SOFTWARE - BASIC

22. 22 2.0KNOW YOUR SOFTWARE - BASIC 2.4Changing elements’ values To add edit an element’s value, double-click on the element’s default value and enter a desired value

23. 23 2.0KNOW YOUR SOFTWARE - BASIC 2.4Changing elements’ values – Add Port To add a port on a specific section of a line, click on the “Ports” icon and select “PORT” Place the port on the schematic section by clicking once on the desired location Adding a port can be also done by clicking on the “Ports” icon from the top toolbar

24. 24 2.0KNOW YOUR SOFTWARE - BASIC 2.4Changing elements’ values – Add Ground To add a ground, click on the “Ground” icon and select it. Click once and an outline of it will appear Place the ground on the schematic section by clicking once on the desired location

25. 25 2.0KNOW YOUR SOFTWARE - BASIC

26. 26 2.0KNOW YOUR SOFTWARE - BASIC 2.5Adding result Graphs & Charts – Add Graph To add a result graph, right-click on the “Graph” icon on the left window and select “Add Graph”. A pop-up window will appear Ensure that the “Proj” tab is selected before adding in any graphs

27. 27 2.0KNOW YOUR SOFTWARE - BASIC 2.5Adding result Graphs & Charts – Graph Types When a pop-up window like this will appear, select the appropriate type of graph Rename the graph as preferred

28. 28 2.0KNOW YOUR SOFTWARE - BASIC 2.5Adding result Graphs & Charts – Add Meas After inserting the appropriate graph type, it still does not know what type of parameters that is to be plotted on it. To define this, right click on the “Graph’s Name” and click on “Add Measurement”

29. 29 2.0KNOW YOUR SOFTWARE - BASIC 2.5Adding result Graphs & Charts – Select Meas A pop-up window like this will appear, select the correct EM Structure’s result to be plotted by selecting the correct Data Source Name Check on the correct parameter. In this case, it is S 21. Ensure that the “dB” checkbox is checked

30. 30 2.0KNOW YOUR SOFTWARE - BASIC 2.5Adding result Graphs & Charts – Simulate To start simulation, click on the Analyze button on the tool bar at the top

31. 31 2.0KNOW YOUR SOFTWARE - BASIC 2.5Adding result Graphs & Charts – Results Filter Design Criteria A good S 11 will have a response at the desired design freq with < -10dB value in pass band A good S 21 will have almost 0dB response in pass band, & infinite response in stop band

32. 32 3.0D.I.Y No. 1 Simulate the following design in MWO. Save the file.

33. 33 3.1KNOW YOUR SOFTWARE - INTERMEDIATE 3.1.1 Selecting & Setting Variables 3.1.2 Analyzing & Tuning

34. 34 3.1KNOW YOUR SOFTWARE - INTERMEDIATE Re-open the file that was saved earlier in DIY No 1.

35. 35 3.1KNOW YOUR SOFTWARE - INTERMEDIATE 3.1.1 Selecting & Setting Variables To start manual tuning of certain parameters in a schematic, the “Tune Tool” in the schematic should be selected

36. 36 3.1KNOW YOUR SOFTWARE - INTERMEDIATE 3.1.1 Selecting & Setting Variables Using the tune tool, select the desired parameter in the schematic to be tuned. When selected its value will turn blue

37. 37 3.1KNOW YOUR SOFTWARE - INTERMEDIATE 3.1.1 Selecting & Setting Variables Invoke the variable tuning toolbar by clicking on the “Tune” button at the top tool bar

38. 38 3.1KNOW YOUR SOFTWARE - INTERMEDIATE 3.1.1 Selecting & Setting Variables A variable tuning toolbar like this will appear before you. The nominal, max and min tunable values/range can be set here by users

39. 39 3.1KNOW YOUR SOFTWARE - INTERMEDIATE 3.1.2 Analyzing & Tuning Click on “Analyze” button and click on the Graph so that the results may be shown. Ensure that the variable tuner tool bar is also easily accessible.

40. 40 3.1KNOW YOUR SOFTWARE - INTERMEDIATE 3.1.2 Analyzing & Tuning Move the variable tuner up and down (to change the L value) and observe the changes in the S 11 and S 21 values in the freq range

41. 41 4.0KNOW YOUR SOFTWARE - ADV 4.1Selecting & Setting Variables 4.2Adding & Setting Optimization Goals 4.3Running an Optimization

42. 42 4.0KNOW YOUR SOFTWARE - ADV

43. 43 4.0KNOW YOUR SOFTWARE - ADV 4.1Selecting & Setting Variables To edit the property of variables for optimization purposes, click on “Simulate” button at the top of window. Select “Optimize” option, OR press “F7” button

44. 44 4.0KNOW YOUR SOFTWARE - ADV 4.1Selecting & Setting Variables A window like this will appear. Click on the “Variables” tab at the bottom of the window to enable variable selection

45. 45 4.0KNOW YOUR SOFTWARE - ADV 4.1Selecting & Setting Variables A window like this will appear. Select all the elements in the schematic and enable both options for tuning and optimization

46. 46 4.0KNOW YOUR SOFTWARE - ADV 4.1Selecting & Setting Variables A pop-up window like this will appear. Select the element’s Value (only) for optimization and tuning. In this case, inductance “L” is selected for tuning & optimization

47. 47 4.0KNOW YOUR SOFTWARE - ADV 4.1Selecting & Setting Variables Another way of having a clearer view when selecting a certain (not all) elements to be tuned and optimized is to double-click on the element in the schematic

48. 48 4.0KNOW YOUR SOFTWARE - ADV

49. 49 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals To set optimization goals, right-click on the “Optimization Goals” icon on the right and select “Add Opt Goal”

50. 50 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals To add a goal so that S 11 less than -10 dB in pass band, ensure that the S 11 measurement is selected here Since this is an LPF with pass band < 2GHz, the range of the goal should start from MIN and stops at 2GHz Click on “OK” button when done setting an optimization goal

51. 51 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals An optimization goal will appear under the “Optimizer Goals” icon when setting is done

52. 52 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals An optimization goal line will also appear in the graph where the optimized measurement is plotted.

53. 53 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals Continue to add on another two more optimization goals, which are both for S 21 ; 1. S 21 is at least -3 dB in pass band 2. S 21 is less than – 10 db in stop band

54. 54 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals Goal 1: S 21 is at least -3 dB in pass band

55. 55 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals Goal 2: S 21 is less than – 10 db in stop band

56. 56 4.0KNOW YOUR SOFTWARE - ADV 4.2Adding & Setting Optimization Goals Optimization goal lines will also appear in the graph where the optimized measurement is plotted. Colors of the lines are according to the measurement types, different measurement has different goal line colors

57. 57 4.0KNOW YOUR SOFTWARE - ADV

58. 58 4.0KNOW YOUR SOFTWARE - ADV 4.3Running an Optimization To start running an optimization, click on “Simulate” and “Optimize” option at the top of the window. User can also press “F7” button

59. 59 4.0KNOW YOUR SOFTWARE - ADV 4.3Running an Optimization Once a window as shown appears, click on the “Start” button. Please also ensure that the “Maximum Iterations” option is set to “5000”

60. 60 4.0KNOW YOUR SOFTWARE - ADV 4.3Running an Optimization When the “Show all iterations” check box is selected, no of iterations during optimization run will be shown here.

61. 61 4.0KNOW YOUR SOFTWARE - ADV 4.3Running an Optimization Final S 11 and S 21 response of the optimized filter is shown in the graph. The optimizer tries to fit curves towards the goal targets, but might not achieve it 100% due to the property of the filter itself

62. 62 4.0KNOW YOUR SOFTWARE - ADV 4.3Running an Optimization Optimized circuit element’s value is shown in this figure

63. 63 5.0 CONCLUSION What you have learnt today?? Revised on design theories learnt in class Applied a theory based design using a simulation software Learnt how to use a software which is capable of simulating various microwave components

64. 64 5.0 REFERENCES Pozar, D.M. (2005) Microwave Engineering 3 rd Ed. John Wiley & Sons, N.J, USA Pozar, D.M. (2001) Microwave and RF Design for Wireless Systems, John Wiley & Sons, N.J, USA

65. 65 6.0 REVISION HISTORY VersionDateCommentsAuthor R01.0022-08-2006Initial DraftP.J Soh R01.0129-08-2006Added Manual Tuning Proc (Section 3.1) P.J Soh