The emerging growth of higher frequency applications is demanding smaller form factors, higher operating frequencies and thinner printed circuit board (PCB) layouts. Planar filters offer significant size and integration advantages, making them more efficient for compact designs. They can also operate at K-Band and beyond, which is critical for emerging new applications in 5G, satellite communications and automotive radar. With favorable and economical manufacturability on PCBs, planar filters also help reduce costs, have good production yields and offer R&D teams design flexibility, which is important when determining potential performance trade-offs.
To help address these emerging trends and growing design challenges, SynMatrix recently released a product update that features diplexer 3D geometry automation workflows and an end-to-end design workflow to support a variety of different microstrip filters.
The microstrip design suite features a powerful GUI interface to enable users to synthesize and generate their parameterized 3D geometries in Ansys HFSS automatically. They can also optimize their filter designs using AI and computer-aided tuning functions. Here is a quick summary of capabilities available to microstrip filter designers:
Lowpass filter applications: Filter synthesis support for Chebyshev, Butterworth and elliptic filters. Users can select from step impedance, open stub and elliptic design types.
Standard microstrip bandpass filters: Design workflow support for edge-coupled, end-coupled, interdigital and hairpin bandpass filters.
Microstrip open-loop coupled bandpass filters: SynMatrix now provides open-loop resonator modeling to help streamline and automate the coupled bandpass filter design workflow.
AI and computer-aided tuning (CAT) optimization tools: SynMatrix has expanded the optimization functions and workflows to support all the microstrip filters previously mentioned.
LOWPASS MICROSTRIP FILTERS
SynMatrix now offers filter synthesis workflows to support lowpass microstrip filters. Users will enjoy a highly customizable environment featuring easy-to-edit circuit analysis pages and automation workflows to help quickly construct and model parameterized 3D geometries. Figure 1 shows some representative geometries.
Figure 1 SynMatrix customizable tool for representative lowpass microstrip filter layouts.
STANDARD PLANAR MICROSTRIP BANDPASS FILTER
SynMatrix now supports the entire design workflow, including synthesis, 3D modeling automation and optimization for edge-coupled, end-coupled hairpin and interdigital filters. Figure 2 shows an example of this workflow for an edge-coupled bandpass filter. For edge-coupled and end-coupled bandpass filters, the SynMatrix design interface also supports end extension, angled with end via, flipped edge-coupled and end-coupled-line configurations.
Figure 2 Example of edge-coupled bandpass filter design interface.
Figure 3 AI-optimized results for edge-coupled bandpass filter structure.
Additionally, with automatically paired parameters, an AI-powered optimization workflow integrated with Ansys HFSS can be used to realize dramatic time savings. The results of this process for an edge-coupled bandpass filter analysis are shown in Figure 3.
MICROSTRIP OPEN-LOOP COUPLED BANDPASS FILTER
Figure 4 Example of a triangular resonator.
SynMatrix now supports open-loop resonator modeling for coupled microstrip bandpass filters. Users can leverage SynMatrix’s first principles design workflow, starting with single resonator analysis, coupling scheme analysis, input and output structure design and full 3D layout and modeling. Users can choose between rectangular, square, triangle hexagon and U-shape resonators; in addition, SynMatrix will enable users to customize and edit the resonator shapes and parameters, such as the line width and insertion depth, to fit design requests optimally. Figure 4 shows the inputs and outputs for a triangular resonator.
Planar filter performance may not match cavity filter performance in scenarios demanding better insertion loss and power handling characteristics. However, the form factor and cost benefits help provide design alternatives for modern RF microwave systems. As planar technology evolves and improves and diplexer design volume and complexity demands continue to grow, productivity and advanced design tools will become increasingly important to help designers meet project timelines, engineering specifications and economic goals.
SynMatrix Technologies Inc.
Richmond Hill, Canada
www.SynMatrixtech.com/