[A-DX] SWRG#325 preview

Roger Thauer
Donnerstag, 05. Oktober 2023, 22:23 Uhr

Welcome to program 325 of Shortwave Radiogram.
...
Here is the lineup for today's program, in MFSK modes as noted:

  1:40  MFSK32: Program preview
  2:48  MFSK32: NASA craft to continue exploring deep space
  6:31  MFSK64: Underground wireless communication may be possible    <==
11:02  MFSK64: This week's images
28:01  MFSK32: Closing announcements

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==> 
https://techxplore.com/news/2023-09-possibility-wireless-communication-40m-underground.html

The team explained that they used a very narrow low-frequency band of 
20kHz, rather than the MHz or GHz range commonly used in general 
wireless communication. This frequency band was chosen to minimize 
material loss in the subterranean or underwater environment, and to suit 
the size of the antennas. The data transmission rate for voice signals 
was maintained at around 4kbps, sufficient for basic two-way communication.

So wie sich das liest:
- Datenübertragung mit einem Sprachcodec  von 4kbps
- gesendet und empfangen wird die magnetische Feld-Komponente (ähnlich 
Ferrit- oder Rahmenantenne)
- verwendeter Frequenzbereich bei 20 kHz Längstwelle, ähnlich SAQ 17,2 kHz.



roger