The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A method of calculation is proposed and total energy losses in one round trip for lower EH1m, TE0m and TM0m modes are obtained numerically for diffraction mirror in the form of a circular diaphragm which placed inside a dielectric circular hollow waveguide. It is shown that the use of diffractive mirrors with large-scale irregularities in a dielectric waveguide resonator is the preferred among intracavity...
The paper describes a numerical technique for calculating transient radiation fields (both near and far zone) of simple conical antennas such as bi-conical, disc-conical, TEM-horn, bow-tie antennas, etc. The method is based on applying mode matching technique to the junction of two conical waveguides one of which is the free space. The problem is considered in time domain, the antenna is excited with...
A new method for waveguide scattering problems analysis is proposed. The method is based on field mode expansion in time domain and mode-matching the fields at a scatter (iris). As an example the problem of diffraction of a pulse wave on an iris in a parallel-plate waveguide is solved and compared against FDTD solution. The main idea is in solving FDTD equations for each mode independently in the...
Periodic structures like gratings or frequency selective surfaces are widely met in antenna design and applications. Some problems require calculating reflectivity in a wide frequency band. Time domain methods like FDTD are beneficial in such problems since they provide the whole spectrum in a single simulation. A periodic structure is modeled as a Floquet waveguide. In FDTD the simulation region...
In order to solve diffraction problems with infinite structures (like waveguides) using FDTD needs some method to bound the numerical solution region with absorbing boundary condition imitating semi-infinite waveguide. In several such techniques are described that use either local conditions (ABC) or absorbing layer (PML), but most of these methods result in unacceptable reflection errors in vicinity...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.