The Application Gallery features COMSOL Multiphysics® tutorial and demo app files pertinent to the electrical, structural, acoustics, fluid, heat, and chemical disciplines. You can use these examples as a starting point for your own simulation work by downloading the tutorial model or demo app file and its accompanying instructions.
Search for tutorials and apps relevant to your area of expertise via the Quick Search feature. Note that many of the examples featured here can also be accessed via the Application Libraries that are built into the COMSOL Multiphysics® software and available from the File menu.
One way to generate circular polarization from a microstrip patch antenna is to truncate the patch radiator. This model is tuned around the GPS frequency range. The axial ratios are calculated to show the degree of circular polarization. Read More
Microstrip filters can be fabricated directly on a printed circuit board (PCB) with a microstrip line going from the input to the output. Along the microstrip line there are a number of stubs of certain lengths and widths. The design of the filter involves choosing the impedance of the ... Read More
It is possible to engineer the structure of materials such that both the permittivity and permeability are negative. Such materials are realized by engineering a periodic structure with features comparable in scale to the wavelength. It is possible to model both the individual unit cells ... Read More
A fractal is a mathematical form showing self-repeating patterns. By virtue of its geometrical properties, a fractal structure can generate multiple resonances in RF applications. This antenna model uses a 3rd order Sierpinski triangle and the calculated S-parameters shows good input ... Read More
The model utilizes a dedicated mesh refinement study, Frequency Domain RF Adaptive Mesh, which dynamically refines the mesh in the region of interest. For the Application Library model Microstrip Patch Antenna, it increases the mesh resolution around areas with high field variations. The ... Read More
One way to design a filter is to use the element values of well-known filter prototypes, such as maximally flat or equal-ripple low-pass filters. It is easier to fabricate a distributed element filter on a microwave substrate than a lumped element filter, since it is cumbersome to find ... Read More
This model uses the Semiconductor and RF modules to describe a photoconductive antenna (PCA). A laser pulse is applied on the surface of undoped LT-GaAs to generate electron-hole-pairs, which move under the influence of an external E-field creating a transient electric current pulse. ... Read More
Some conventional three-port power dividers are resistive power dividers and T-junction power dividers. Such dividers are either lossy or not matched to the system reference impedance at all ports. In addition, isolation between two coupled ports is not guaranteed. The Wilkinson power ... Read More
Multiscale modeling is a challenging issue in modern simulation. This occurs when there are vastly different scales in the same model. For example, your cell phone is approximately 10 cm, yet it receives GPS information from satellites 20,000 km away. In these models we examine several ... Read More
Feeding antennas with proper signals can be difficult. The signal is often described as a voltage, and voltages are not well defined in electromagnetic wave formulations. There are several tricks to model voltage generators in such situations, and one is the magnetic frill. This model ... Read More