1D frequency-domain solutions are compared against Leroi [http://www.amirainternational.com/WEB/site.asp?section=news&page=projectpages/p223f_software]
== Frequency-domain closed-loop source ==
[[Image(Leroi_ecomp.png)]][[Image(Leroi_ediff.png)]]
Above, a comparison of Lemma with Leroi for a square closed-loop source transmitting 20 Amps at 50 kHz. Both solutions are in excellent agreement (left). The difference plot shows that the two codes fall within .1% throughout, with minor differences focused near the corners of the loop. Calculations were made at the air-earth interface.
[[Image(Leroi_ecomp_20m.png)]][[Image(Leroi_ediff_20m.png)]]
Same as the above plots, but calculations were made at 20m depth.
[[Image(Leroi_bcomp_20m_real.png)]][[Image(Leroi_bdiff_20m_real.png)]]
In this plot, the horizontal components of the B field are shown at 20 m of depth.
[[Image(Leroi_bcomp_20m_imag.png)]][[Image(Leroi_bdiff_20m_imag.png)]]
In all of these cases Lemma is in excellent agreement with Leroi, the main differences can be seen in fairly low-order effects near the loop corners. This difference can be attributed to the fact that Lemma integrates around a current source, using horizontal electric dipoles (HED). Leroi and most other codes decompose the surface area of the loop and approximate the surface with vertical magnetic dipoles (VMD). The VMD approach will therefore smooth out sharp corners. However, in reality, wires do not make perfectly sharp corners, and either approach is valid.