Filters and Stubs
R2026bUse the filter and stub objects and functions to create and visualize filters and stubs used in a printed circuit board (PCB).
RF and microwave filters are used to select or reject a particular band of frequencies in receivers, transmitters, and frequency synthesizers.
Radial stubs are used in antenna impedance matching circuits, frequency selective filters, and resonant circuits for UHF electronic oscillators and RF amplifiers.
Objects
Functions
show | Display PCB component structure or PCB shape |
info | Display information about PCB component structure |
pcbcascade | Create new component using cascade operation |
shapes | Extract all metal layer shapes of PCB component |
residue | Extract lowpass admittance residues and poles of a measuredFilter
object (Since R2024a) |
transversalMat | Calculate the transversal matrix of a measuredFilter
object (Since R2024a) |
canonicalCouplingMat | Perform canonical matrix rotation (Since R2024a) |
optimize | Isospectral optimization of a measuredFilter object (Since R2024a) |
qualityfactor | Calculates the unloaded quality factor of a measuredFilter
object (Since R2024a) |
design | Design stepped impedance low pass filter around desired cut-off frequency |
design | Design hairpin filter around specified frequency |
resweep | Center frequency and bandwidth scaling of measured filter (Since R2026b) |
Featured Examples
Filter in Shielded Enclosure
Design and analyze a filter with a shielded enclosure. PCBs often experience unwanted problems such as electromagnetic interference (EMI) leading to performance degradation and failure. It may also affect other sensitive electronics due to outgoing EMI. In an ideal world, a shield would completely block off these EMI and it ensures that strong signals cannot escape. A single-stub filter enclosed in a Faraday shield is analyzed using Finite Element Method (FEM).
Model and Analyze Microstrip Diplexer Using Open Loop Resonator
Model and analyze a microstrip diplexer with the open loop resonator using RF PCB Toolbox™.
Miniaturization and Bandstop Region Improvement of Stub Filter Using Double Spurline
Introduce a double spurline into a conventional open stub filter for filter circuit size miniaturization and bandstop region improvement using RF PCB Toolbox™.
Microstrip Ultra-Wideband Bandpass Filter with Cascaded Broadband Bandpass and Bandstop Filters
Create a compact ultra-wideband filter by connecting a broadband bandstop filter with a broadband bandpass filter.
UWB Bandpass Filter Using Open and Short-Circuited Stubs
Create an open or short circuited stub filter using the filterStub catalog and analyze the filter using RF PCB Toolbox™.
Comparison of Lumped and Distributed EM Models for Low Pass Filters
Compare lumped and distributed electromagnetic (EM) model for low pass filters.
Variations of Open and Short Stub Filters
Analyze the open and short stub filters using RF PCB Toolbox™.
Microstrip Composite Bandpass Filters for Ultra-Wideband (UWB) Wireless Communications
Design and analyze a Low Pass Filter (LPF), High Pass Filter (HPF), and cascade responses of the LPF and HPF as well as two variations of a composite filter as shown in the paper[1].
Stepped Impedance Maximally Flat Lowpass Filter for Microwave Applications
Comparison of S-parameters of simulated and lumped element stepped impedance low pass filter for X-band applications.
Bandstop and Bandpass Filters with Open Microstrip Line Stubs Using Behavioral and EM Simulation
Use behavioral and EM simulation for bandstop and bandpass filters.
Design and Analysis of Hairpin Micro-Strip Line Bandpass Filter
Design and analyze a hairpin microstrip filter.
Optimize Enclosure for Edge-Coupled Filter Using SADEA Optimizer
Optimize the enclosure for an edge-coupled filter using the SADEA optimizer. The goal is to minimize enclosure-induced resonances that degrade filter performance. SADEA is a surrogate-assisted optimization method that uses mathematical models to approximate expensive electromagnetic (EM) simulations, significantly improving computational efficiency. It is particularly effective when the design space contains a small number of variables.
