The Application Gallery features COMSOL Multiphysics tutorial and demo app files pertinent to the electrical, mechanical, fluid, and chemical disciplines. You can download ready-to-use tutorial models and demo apps with step-by-step instructions for how to create them yourself. The examples in the gallery serve as a great starting point for your own simulation work.

Use the Quick Search to find tutorials and apps relevant to your area of expertise. Log in or create a COMSOL Access account that is associated with a valid COMSOL license to download the MPH-files.

Quarter-Wave Transformer

Transmission lines are used when the frequency of the electromagnetic signals is so high that the wave nature of the signals must be taken into account. A consequence of the wave nature is that the signals are reflected if there are abrupt changes of the characteristic impedance along the transmission line. Similarly, the load impedance, Z(L), at the end of the transmission line must match its ...

Rat-Race Coupler

A 180° Ring Hybrid (Rat-Race Coupler) is a four-port network with 180° phase difference between two ports. It is cheaper to manufacture this type of microstrip line component compared to a wave guide 180° hybrid junction, so called magic-T. The objective of this model is to compute the S-parameters and to observe the matching, isolation, and coupling around the operating frequency.

Simulation of an Electromagnetic Sounding Method for Oil Prospecting

The marine controlled source electromagnetics method (CSEM) for oil prospecting has emerged as a promising technique during recent years. This model demonstrates one variant of it. It uses a mobile horizontal 1 Hz electric dipole antenna that is towed 150 m above the sea floor. An array of sea floor receivers measure the electric field at various distances away from the antenna. When measuring ...

Frequency Selective Surface Simulator

Frequency selective surfaces (FSS) are periodic structures that generate a bandpass or a bandstop frequency response. They are used to filter or block RF; microwave; or, in fact, any electromagnetic wave frequency. For example, you see these selective surfaces on the doors of microwave ovens, which allow you to view the food being heated without being heated yourself in the process. The ...

Cascaded Rectangular Cavity Filter

A cascaded cavity filter provides much better bandpass filter performance compared to a single cavity. Out-of-band rejection improves dramatically using a cascaded design. This model uses three rectangular cavity filters coupled via slots. The calculated S-parameters show excellent out-of-band rejection.

Modeling a Biconical Antenna for EMI/EMC Testing

Biconical antennas are popular for very high frequency (VHF) measurement because they support a wide frequency range. They are also useful for electromagnetic compatibility (EMC) testing where the antenna can be used as an RF source in susceptibility or immunity test. This model simulates a biconical antenna made of lightweight hexagonal frames that are preferred over solid cones for ...

Thermal Drift in a Microwave Cavity Filter

Microwave filters are used to eliminate unwanted frequency components in the output from microwave transmitters. They are typically inserted between a power amplifier and an antenna. The amplifiers are nonlinear and produce harmonics that must be eliminated with filters that have a rather narrow passband. Due to high power loads but also possibly from harsh environmental conditions (such as a ...

TM Mode Microwave Plasma

This model shows how to simulate a TM mode microwave plasma by using the Doppler broadening parameter to smooth out the resonance zone, which occurs on the contour of critical electron density. A detailed explanation of the underlying physics of this model can be found in the blog entry "Application Note on Microwave Discharges".

Corrugated Circular Horn Antenna

The excited TE mode from a circular waveguide passes along the corrugated inner surface of a circular horn antenna where a TM mode is also generated. When combined, these two modes give lower cross-polarization at the antenna aperture. By using this application, the antenna radiation characteristics, as well as aperture cross-polarization ratio can be improved by modifying the geometry of the ...

Designing a Waveguide Diplexer for the 5G Mobile Network

A diplexer is a device that combines or splits signals into two different frequency bands, widely used in mobile communication systems. This model simulates splitting properties using a simplified 2D geometry. The computed S-parameters and electric fields at the lower and upper bands will show the diplexer characteristics in the Ka-band.