Review of electromagnetic field calculations by digital linear filtering
Article first published online: 7 DEC 2012
Copyright 1982 by the American Geophysical Union.
Volume 17, Issue 5, pages 1067–1085, September-October 1982
How to Cite
1982), Review of electromagnetic field calculations by digital linear filtering, Radio Sci., 17(5), 1067–1085, doi:10.1029/RS017i005p01067.(
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Accepted: 11 JAN 1982
- Manuscript Received: 27 AUG 1981
The determination of electromagnetic fields over layered earth structures involves evaluation of the Hankel transform integrals. The classical method of numerical integration is very tedious, as it involves evaluating infinite integrals containing product functions with Bessel functions that are oscillatory and thus time consuming even on high-speed digital computers. In contrast, the digital linear filter (convolution) method, which avoids Bessel function evaluations, is extremely rapid with regard to the ease with which it can be applied and to speed of calculations, and it provides accurate (five or more decimal accuracy) results. The speed of calculations can be further significantly increased while maintaining the same accuracy using a variable convolution approach. In some cases, the digital linear filter method has proved to be more rapid in calculations than the fast Fourier transform method.