Why do we need frequency domain?
Grid
0
Best Answer

@PankajKumarDas,
Converting geophysical data from the space (or time) domain to the frequency domain (via Fast Fourier Transform) is common practice in geophysics, particularly when wanting to apply some sort of filter to that data.
We do this because it is more computationally efficient to filter data in the frequency domain compared to the space domain. For example, applying a filter such as a first vertical derivative to a grid of magnetic data in the space domain requires convolution using a twodimensional filter. Depending on the type of filter, that process can be complex and therefore computationally expensive.
Transforming the data and the filter to the frequency domain allows us to simply multiply the two to get a filtered spectrum, which is then transformed back to a filtered grid in the space domain. This process is far more computationally efficient than convolution.
The following diagram describes the distinction between space and frequency domain filtering. It is taken from Reeves (2005), which you can access here: http://www.geosoft.com/media/uploads/resources/technicalpapers/Aeromagnetic_Survey_Reeves.pdf
I'd urge you to download the document and review Chapter 6, from which the diagram is taken.
Best regards,
6
Answers

Thank you very much Sir.0
This discussion has been closed.
Categories
 627 All Categories
 35 Products & Software
 3 Seequent
 141 Leapfrog
 324 Geosoft
 5 GeoStudio
 1 Developers
 Seequent Evo APIs
 154 GX Developer
 Early Access Programmes
 1 Oasis montaj Field EAP