What does FDE mean in UNCLASSIFIED

A finite difference eigenmode is a numerical technique used to model electromagnetic wave propagation in waveguides and cavities. It can be used to calculate the modes, frequencies, field patterns, and mode numbers of these electromagnetic structures.

Finite Difference Eigenmode works by discretizing the continuous waves into discrete grid points using the finite difference method. From this grid of data it then uses an eigenvalue/eigenvector approach to determine the frequency and pattern of wave propagation in the structure.

The main advantages of Finite Difference Eigenmode are that it can quickly and easily generate accurate results for wave propagation in complex geometries with minimal computational resources. Additionally, FDE can be used to analyze structures that would otherwise be too complicated for more traditional methods such as boundary element or moment methods.

Finite Difference Eigenmodes can be used to analyze any structure that has a cavity with two or more dimensions such as rectangular waveguide, circular waveguide, microstrip line, helical antennae, circularly polarized antennae and free-space propagating fields.

One potential drawback is that compared to other techniques such as finite element method (FEM), FDE requires more computational resources for certain problems due to its higher discretization requirement. Additionally FDE may not accurately capture certain physical effects such as losses caused through radiative sources.

Before modeling an electromagnetic system using FDE it is important to assume a particular boundary condition such as electric field or magnetic field type at each of the boundaries within the system being modeled. Additionally one should also consider whether there are any external fields present which could influence the overall behavior of the system under study.

No, FDE only allows for linear systems since its underlying principles assume linearity throughout all equations and thus cannot account for non-linear behavior which is present in some systems. To analyze non-linear equations one should use a finite element method (FEM) or another suitable approach for dealing with non-linear equations.

Once a solution has been obtained from a given set of parameters i.e., frequency range or mesh size etc., parameter alterations may be performed by way of re-running simulations from scratch or alternatively by performing parameter sweeps where multiple runs are carried out after changing just one parameter at each step within the sweep range specified by the user beforehand.

Yes, most approaches utilizing FDE require specialized software packages specifically designed for carrying out electromagnetic analyses with this technique although many user friendly versions exist allowing users without specialized knowledge to obtain reasonably accurate results quickly and easily.