EM wave biological by-products Electromagnetic precursors
The Woodpecker signal has allegedly biological by-products according to the corresponding website section. Could these be related to the so-called electromagnetic precursors? (Reference: Electromagnetic Precursors in Complex Layered Media") Below is described how electromagnetic waves of a certain frequency can be "fractionated" to other frequencies, when they transverse a medium. Health studies of electromagnetic waves should predict those. The PAVE PAWS study by the NASEM has referred to these.
Electromagnetic waves, including ultrawide waves, propagating in a medium like the atmosphere or the human body may be refracted and dispersed.
Different frequencies may appear ahead of the main (bulk) signal. These are called precursors or forerunners and are of two kinds: Sommerfeld and Brillouin precursors.
Health studies should predict those frequencies and their role.
A related analysis has been included in the report of the U.S. National Academies of Science for the signal of the RADAR "PAVE Phased-Array-Warning System" (covering the entire U.S.).
***********************************************************************
Refraction and dispersion
A straw immersed in a glass of water may appear distorted or "refracted" (fractioned). A certain segment may appear as it has "deviated" by a certain angle.
That is because when the light enters the water, it may be refracted: it changes direction or it is deviated by a specific angle.
When a light beam, which is an electromagnetic wave consisting of seven frequencies, enters a prism, it is refracted, that is, it is deviated, with each of the seven frequencies being deviated by a different angle.
As a result, the fine light beam is dispersed into a sum of different frequency beams. The larger the deviation angles the larger the dispersion.
When an ultrawide electromagnetic signal composed of different frequencies, low and high, propagates in a medium like the atmosphere or the human body, it may be refracted and dispersed. Those media may be called dispersive.
We may note that before the main (bulk) signal arrives, some high frequencies may appear (first precursor) followed by some low frequencies (second precursor). Both of these have a lower amplitude than the main signal as shown in "Figure 1b" and are called respectively the Sommerfeld and Brillouin precursors.
The mentioned figure is adapted from Brillouin's book in the reference "On the Nature of the Sommerfeld-Brillouin Forerunners (or Precursors)" https://arxiv.org/abs/1911.03590
Reference for Refraction and Dispersion:
