Monday, November 07, 2016

USCG Transmitting DRM Data on 5200 kHz

Courtesy of RadioMagOnline

Token, a longtime member of the UDXF HF utility group, has posted on their newsgroup that he is receiving DRM transmission from the US Coast Guard from his Mohave Desert, California listening post.

From his post: " couple of times now I have caught DRM like short transmissions on 5200 kHz, but I don’t really do DRM, and when I see it I assume it is broadcast oriented.  Last night I saw it again and since it was on no BC schedule I could find I looked closer.
"At about 0110 UTC on 6 November, 2016, on 5200 kHz the DRM signal was not strong, but the waterfall showed it had been on for at least 20 minutes.  I looked at the signal using the DRM decoder built into the Elad SW2 (the only DRM decoder I have).  No audio was demodulated, I have no idea if tis is because of incorrect settings, low SNR, or if there indeed was no audio.  However, the ID Tag said “USCG Journaline”, could USCG mean US Coast Guard?

 "I posted the log to HFUnderground and kilokat7-MI informed me that Journaline is a text data mode of DRM.

"Further research shows the following links:

 "I believe there is a good possibility what I heard was US Coast Guard usage of DRM.

 "I noticed the transmission at about 0110 UTC, and it was up for at least 20 minutes before that.  It apparently continued all night and it eventually faded out with propagation at about 1600 UTC.  Antenna bearings and propagation were consistent with the source possibly being Kodiak Alaska."

From his 7 Nov 2016 post to UDXF he had a bit more information on the 5200 kHz broadcast:

"This USCG DRM signal on 5200 kHz was up before 0100z today, 7 November, 2016. I have a couple of DRM programs running now.  I see that the signal contains at least 4 data channels, they are labeled:

1 USCG Journaline | Data: Journaline (11.04 kbps)
2 USCG AIS DATA | Data: (11.04 kbps)
3 Binary File Pool | Data: (11.04 kbps)
4 Quality Test | Data: Unknown Service (0.60 kbps)
"No audio heard so far, I don’t know if I have incorrect settings or if there is indeed no data on the signal.
"Selecting the Journaline data line you find multiple lines of information, from safety bulletins, weather reports, etc, to ESPN sports results. Here is a video of the signal at my location, with decodes and the data currently being shown."
From the link listed above it appears the transmitter sites are located in New London, CT and Kodiak, AK according to the following document:

"Background The U.S. Coast Guard (USCG) Research and Development Center (RDC) has an ongoing project titled: Next Generation Arctic Navigational Safety Information System (ANSIS). There is considerable concern over the increasing maritime activity in the Arctic, along with the potential for maritime accidents and serious environmental harm to the fragile Arctic environment, warranting the need to implement enhanced maritime safety measures. One challenge is that the dynamic, constantly changing environmental and safety information, which mariners need to identify, assess, and mitigate the risks of operating in the Arctic, is not presently available due to the lack of infrastructure and suitable communications capability. A Cooperative Research and Development Agreement (CRADA) between the U.S. Coast Guard (USCG) RDC and Marine Exchange Alaska (MXAK) was established to promote a public-private analysis and eventual solution to this problem.

"The USCG RDC's objective for this project (CRADA) is to define, develop, demonstrate, and evaluate, in an operational setting, at least one promising technology approach to the "Next Generation Arctic Maritime Navigational Safety Information System," which provides important, time-critical, information to mariners in order that they may better access and manage their voyage risks as they transit the remote and hostile waters of the US Arctic Exclusive Economic Zone (EEZ). MXAK has expressed their agreement to support this objective.

"The project is currently using AIS transmit capabilities in Alaska to transmit Maritime Safety Information (MSI) information using mobile maritime VHF frequencies AIS1 and AIS2. The range of this transmission is limited to line of site between the shore station and the ship off shore. This is typically twenty (20) nautical miles (nm). This system would require spacing transmit sites along the Alaskan coast line closely together where no infrastructure exists.

"The USCG RDC is interested in testing the RF propagation characteristics of using Digital Radio Mondiale (DRM) with High Frequency (HF) as a means to broadcast digital data. This capability will allow transmission of detailed weather information, ice edge information, notice to mariner information, and electronic chart updates. If successful, the USCG will investigate using the system to enhance existing means of disseminating digital maritime safety information."

This is a pretty interesting development and one that we will definitely follow here on the Milcom MP blog. If you have one of the RTL-SDR dongles or the Airspy/Spyverter receive packages be sure to check out the RTL-SDR website at how to receive DRM transmissions via those receivers.