High-frequency Emergency and Rural Multimedia Exchange System

Source - Hermes // rhizomatica

The take form the ham community
NSF/Mozilla contest awards $400K for HF linked EMCOM cell net idea


Money quote:
"The solution, which integrates GSM and HF backhaul technology, can provide connectivity to places struck be natural disasters or populations living in remote areas. As the system does not rely on cables or satellites, it could also be used as a backup system for primary communications systems. ... We have essentially married VoIP, GSM and HF so that users can send a text or voice message from their phone across the world without the need for a satellite."

Also bullet 4 / Resources ("read more" down arrow), Documentation,

HF RADIO PARAMETERS

Transmission mode: Single Side Band
RF signal path: Near Vertical Incidence Skywave (NVIS)
Channel width: 2.5 kHz
Frequencies: between 5 and 7 MHz
Power output: 10 W – 100 W adjustable
Adaptive digital modulation modes: 4FSK, 4PSK, 16QAM, ranging from 1 to 10 carriers and different symbol rates, all with Reed Solomon Forward Error Correction


A pico cell (or a full cell using GSM) linked via a NVIS HF SME system.

Software components from at least two licensed Hams are also referenced here, the ARDOP (Amateur Radio Digital Open Protocol) TNC implementation by John Wiseman (GM8BPQ) and D-RATS is a free, easy to use, multi-platform program for data communications with D-STAR devices by Dan Smith (KK7DS).

Check the links for the full story.

Video w/English subtitles

 

This is a very interesting article! I think I understand most of how it is done; however, details are sketchy. I think the gist is they started they own local cellular network then used HF for the long-haul portion. I don't have time to dig into it now as have a ton of work but hope to do so later to answer such questions as: Must it be GSM? Are the HF links in the amateur band? Could something like this be legally implemented in the US? How does it make the connection into other government and private cellular networks as seems tariffs, gateway costs, lease agreements or etc. would need to be implemented or is it a closed network?

Anyway, really interesting! The video, while also interesting, isn't very helpful to describe exactly how the network is accomplished and what it's strengths and limitations.

 

I'm wondering who the control operators for the HF stations will be...after all, technically they have to be in control of all traffic transmitted from their station....

Nice concept...but not for me. And that's all I'm going to say.

 

is this significantly different from WinLink? I've been meaning to look into that for years.

 

The way i read it is that instead of cell towers, the system uses hf transceivers to link between what would typically be cell sites.