German Ny S4285 Fleet Broadcast

 Last update: 30th June, 2022

German-Ny STANAG-4285 fleet broadcast is compliant to the common NATO standard (600bps/L submode, 7-bit stream and KW-46 encryption) but uses a different "format" in some channels where the 600bps/Sort submode is used. In these channels German-Ny adopts a 7-bit framing consisting of

[5-bit data (encrypted)] + [one parity bit(even parity)] + [one pahsing bit]

Such composed stream is differential encoded and then forwarded to the S4285 modem. Each 773 frames (5411-bit length blocks) a sequence of 588 bit length is inserted into the stream: that sequences have still an obscure meaning to me, probably a kind of CRC block (see the related post).

Fig. 1

 The table below reports frequencies and relative STANAG-4285 submodes:


Freq. (KHz/USB) 600bps/L 600bps/S Notes
1897.20

300bps
2623.20

2658.10

2810.20

3247.20

3805.20

4000.20

4081.20

4203.20

4228.20

4463.20

5816.00

6763.20

6778.20

7454.20

7511.20

10561.20

11578.20

12280.20

18 9 9

The Tx sites of the S4285 600bps/S broadcasts are reported in the figures 2,3 all TDoA checked. 
 
Fig. 7

Fig. 8

It's to notice that "All signals in the STANAG-4285 modulation come from Gluecksburg (DHJ58), which the only (!) CommCen of the German Navy. The well-known TX-sites in Neuharlingersiel, Schortens, Marlow, Rostock - Hohe Duene etc. are remote-controlled from DHJ58. This was already published in relevant specialist media in 2012 and 2014.However, the Gluecksburg location is also in question since 2011, as the Ministry of Defense Germany wants to close the Gluecksburg location. A transfer to the (new) Maritime Command in Rostock is planned by 2030" as my friend Thomas (tiNg) from UDXF group reports.
 

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