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Loggings => Utility => Topic started by: jFarley on November 27, 2015, 2247 UTC

Title: LINK-11 6928 USB 2245 UTC 27Nov15
Post by: jFarley on November 27, 2015, 2247 UTC
The presumed LINK-11 which occasionally shows up here around local SS being noted at weak to fair level
Title: Re: LINK-11 6928 USB 2245 UTC 27Nov15
Post by: Token on November 28, 2015, 1622 UTC
I believe this is a 6928.5 kHz ISB transmission of Link 11 out of Europe or that general region.

T!
Title: Re: LINK-11 6928 USB 2245 UTC 27Nov15
Post by: jFarley on November 28, 2015, 2134 UTC
Thanks T!
Title: Re: LINK-11 6928 USB 2245 UTC 27Nov15
Post by: Normz on August 02, 2020, 0750 UTC
I believe this is a 6928.5 kHz ISB transmission of Link 11 out of Europe or that general region.

T!
what is link 11 is it military or general com's, also what is ISB' I dont understand.

Nova
Title: Re: LINK-11 6928 USB 2245 UTC 27Nov15
Post by: Token on August 02, 2020, 1451 UTC
I believe this is a 6928.5 kHz ISB transmission of Link 11 out of Europe or that general region.

T!
what is link 11 is it military or general com's, also what is ISB' I dont understand.

Nova

Link-11 is military.  Link-11 is a tactical data link that allows one platform (ship, aircraft, submarine, etc) to share its tactical picture with any other platforms in the network.  If one ship in a task group sees a target on its radar (sonar, passive sensors, etc) that track data is passed out to everyone, so everyone can see that track, even if their radar or other sensors cannot actually see the target.  There are many advantages to such a system, but one might be that of 12 ships in a task group only one has its radar turned on, providing a radar picture to everyone while the other 11 ships do not give away their position or condition by their radar emissions.

Link-11 was developed for the US Navy, but it has become a NATO forces standard.  It is in the process of being replaced by Link-22.  As Link-22 is backwards compatible to Link-11, this signal might actually be Link-22 in a Link-11 mode.

ISB is Independent SideBand.  This is sending both USB and LSB at the same time, but potentially with different data in each sideband, doubling the data rate.  Or,  alternately, a single frequency can support two different Link-11 networks, with some platforms in both networks, and some in either or.

T!
Title: Re: LINK-11 6928 USB 2245 UTC 27Nov15
Post by: kris on August 04, 2020, 2230 UTC
To Token - - also thank you for the clarification!
I saw SSB transmissions where the lower band was different from the upper one and it surprised me, because the propagation conditions could not change the spectrum image anyway.