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RF Electronics Chapter 7: RF Filters Page 266 2022, C. J. Kikkert, James Cook University, ISBN 978-0-6486803-9-0. This technique of using extraction ports on the PCB border was used for including the PCB border shown in figure 7.46 in the EM simulations shown in figures 7.51 and 7.52. Since the layouts for each of the EM simulations are different, a different extraction name needs to be used for each of the EM simulations. To produce the circuit schematic for circuit 4, the schematic for circuit 3 (3_Hairpin EM PCBRing) was duplicated and renamed "hairpin EM Box_PCBRing". The extraction Group Name of each of the elements then needs to be changed from: EM_Extract to EM_Exctract_Box. This is done by viewing the layout of circuit 5, selecting all and then selecting Element Properties and in the Model Options, change the Group Name to EM_Extract_Box. That will change all the elements at once. Before any EM simulation is carried out check that all the elements are linked to the EXTRACT element in the schematic, by left clicking on it. All the linked elements show up in red. While keeping the EXTRACT element selected, select View View Layout. All the elements to be included in the EM simulation, should be shown in red and should all be joined correctly. All the 5 circuits can then be simulated. If the EM simulation fails, some Extraction Control Block Properties may need to be changed. Firstly ensure the values are set to their default values, as V13 has different simulation settings to earlier versions. This is done by right clicking on the "extract element". Then selecting properties and in the Extraction Control Block Properties window, select AXIEM and click reset defaults. If this fails to resolve the problem, change the parameters that caused the simulation failure as shown in the status window. Figure 7.91. 3D Layout of hairpin filter of figure 7.89 with mesh shown. AXIEM produces a mesh for the circuit layouts and uses those meshed elements to perform the EM analysis. To see the mesh, select the relevant structure in EM Structures such as: EM_Box_Hairpin_SRing of figure 7.91, right click on that structure and select Mesh. Selecting View and View EM Layout, will show the 2D mesh, as shown in figure 7.92. Note the way that the meshing is performed in the bends of the hairpin filter. Figure 7.93 shows a close-up of the meshing applied to the bends of the hairpin filters for the AXIEM simulation (left) and the EMSight simulation (right). It can be seen that RF Electronics: Design and Simulation 266 www.cadence.com/go/awr

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