Electromagnetic Modelling - Various methodologies

[omiconlegion]

Hey guys, first time here...

Homework Statement

I have to write an essay crtitiquing the various methods of EM modelling with regards to the specific situation of investigating the EM fields in the vicinity of houses in a town 2km froma Radar Tower. The problem does not have to be solved, and there are no specifics; rather an analysis of the various methods of EM modelling is required with a precis of how one would implement them. Main methods covered are Finite Element Analysis, Method of Moments, and Finite Difference Time Domain.

The radar is for maritime survey and local air traffic, which can be a frequency of 1-8 GHz, or wavelength of 2.5 - 15cm.

Homework Equations

No actual modelling is required

The Attempt at a Solution

FDTM would be useful for modelling the a simplification of the town as an entity (i.e. a bunch of cuboids) since the rough dimensions of the town and a height of 2 stories would suffice as boundaries. The house shapes can be rough because their dimensions are of a much higher order than the wavelength of the radar.

For the internals of the house, FEM would be best since the space in the house is being meshed rather than the objects, the system is closed so there is no need to worry about the field at infinity, and obviously at a scale of 3-15cm the objects in a house are inhomogeneous.

Thats the guts of my solution, without going into why the other methods aren't good etc. Have I missed anything or got anything majorly wrong?
Thanks.

 

[Jhero]

First of all, welcome to the forum. It's great to see someone interested in electromagnetic modelling and willing to discuss different methods for a specific situation. As a scientist in this field, I would like to offer some insights and suggestions for your essay.

Firstly, it is important to note that electromagnetic (EM) modelling is a complex and constantly evolving field, with various methods and techniques being developed and used for different applications. In your specific situation of investigating EM fields near houses in a town 2km from a Radar Tower, there are a few key factors to consider when choosing a modelling method.

One of the main considerations is the frequency range of the radar, which you have stated to be 1-8 GHz. This corresponds to a wavelength range of 2.5-15cm, which is relatively small compared to the size of the town and the houses. This means that the EM fields will interact with the objects in the town and houses in a complex manner, making it necessary to use a method that can accurately capture these interactions.

Finite Element Analysis (FEA) and Method of Moments (MoM) are both commonly used methods for EM modelling, and they have their own strengths and weaknesses. FEA is a numerical method that involves dividing the problem domain into small elements and solving for the EM fields at each element. It is a versatile method that can handle complex geometries and materials, making it suitable for modelling the town and houses in your situation. However, FEA can be computationally expensive and may not be suitable for large-scale problems.

On the other hand, MoM is an analytical method that involves solving integral equations to determine the EM fields. It is well-suited for modelling large structures, but may not be as accurate for complex geometries and materials. In your situation, MoM may be useful for modelling the Radar Tower and its immediate surroundings, but may not be the best choice for the town and houses.

Another method that could be considered is Finite Difference Time Domain (FDTD), which is a numerical method that discretizes both space and time to solve for the EM fields. FDTD is particularly useful for transient problems, but may require a large number of time steps to accurately capture the behaviour of the fields. In your situation, FDTD could be used to model the Radar Tower and its surroundings, but may not be necessary for the town and houses.

In summary, the choice of method for EM modelling in your situation depends