ELF-VLF waves

"Why are ELF/VLF Waves Useful for Engineers and Scientists? What Are the Practical Benefits of ELF/VLF Research?"

The responses are provided at this page of the Stanfold ELF/VLF group.

Some additional comments:

Their features include the following:

1. They travel by reflection in the ionosphere globally, around the planet without attenuation.

2. They travel by ground propagation around the planet.

3. They penetrate not just walls and buildings, but also underground and underwater great depths.

4. ELF are in the brainwave range and in the biological ion resonance range.

They are applicable to:

1. Air and missile defense (intercontinental), ground and underwater defense.

2. Global communications, including for defense purposes and including underwater (Navy).

3. Global imaging systems, including Earth tomography e.g., for underground exploration (surface NMR) and underground base detection

4. Biological signaling, including brain function influence, such as with ELF modulation as it has been proven by R. Adey.

Noting an ELF-like signal, The Russian Woodpecker. This signal had ELF-related features.

Also, why had it been alleged that it induced NMR? Is that related to the magnetic resonance frequencies of biological ions?

From the book "The Body Electric" by Robert Becker (Author), Gary Selden (Contributor), p.324 

"He said it acts as a crude over-the-horizon radar that would pick up a massive first strike of U.S. missiles if Soviet spy satellites and other detectors were knocked out. 

Second, the signal's modulations are an ELF medium for communicating with submarines underwater. 

Third, he claimed the signal has a biological by-product".

The WALDO ELF/VLF/LF radio data repository

WALDO is a repository of publicly available ELF/VLF/LF radio data, which is used to study the physics of lightning, the ionosphere, and the magnetosphere. It is a joint effort between Georgia Tech and CU-Denver, using data collected by Stanford University from the 1970s until 2016, and then by both Georgia Tech and CU-Denver starting in 2014. The team notes: "Our hope is for the broader community to think of new ways to analyze these datasets that have not been previously considered."

Cited reference: https://eos.org/science-updates/returning-lightning-data-to-the-cloud

Waldo: https://waldo.world

VLF transmission from Antarctica generates “whistler VLF” (“broadband VLF”) wave received in Canada 

We transmit a one-second pulse of 3 kHz (VLF) from Siple Station, Antarctica (top left image).

What do we receive in Quebec, Canada?

“VLF wave-injection experiments from Siple Station, Antarctica” (1987)

Classic experiments such as this are still being studied.

https://vlfstanford.ku.edu.tr/biblio/vlf-wave-injection-experiments-siple-station-antarctica-1/

It is shown in the lower left image. We receive a signal that starts by being similar to the one we transmitted. We then note that an additional signal has been triggered: a signal of increasing frequency (riser) from 3 kHz to 3.5 kHz. 

The received signal is called a “whistler wave” or “whistler” and constitutes a “broadband” VLF signal as it encompasses a broad band of frequencies. In this case it has a bandwidth of 0.5 kHz (500 Hz).

Why is this VLF waveform called a whistler? 

Humans can hear sounds that have frequencies from 20 Hz to 20 kHz. If the above electromagnetic signal is converted to audio, it will sound like whistling or like a musical tone of ascending pitch.

You can listen to a whistler at this video https://youtu.be/-jpe8EfGg48?t=40 at approximately 40 seconds.

This signal propagation is referred to as “whistler-mode” propagation.

Figure 3: Transmission of a one-second pulse of 3 kHz (VLF) from Siple Station, Antarctica (top left image). Signal reception in Quebec, Canada.