Read the forum code of contact
By: - 13th January 2005 at 10:56 Permalink - Edited 1st January 1970 at 01:00
The Short answer to this is they don't - mainly as any efficient communication involves surfacing and potentialy giving your position away. However Very Low Frequency Radio can penetrate water but is very ineffecient for information transfer (75 Baud TG at best) I beleive that for short range contact (Sub-Ship-Sub) they can use some kind of phone which (I think) works on an inductive loop ( A bit like phones for the hard of hearing) but don't quote me on it.
By: - 13th January 2005 at 11:20 Permalink - Edited 1st January 1970 at 01:00
Yes I understand that using extremely low frequency (ELF) they can "communicate" upto depths of 40 meters, however - as you also have said - the data rate is so low that it can only be used for passing launching codes etc...
I wanted to know if there was any "high-speed" communication channel available, whilst being underwater.
By: - 13th January 2005 at 11:22 Permalink - Edited 1st January 1970 at 01:00
there's a brief description of underwater submarine communication in Clancy's Red Storm Rising, when captain Dan McCafferty in the USS Chicago talks to the USS Providence's skipper. unfortunately i dont have that book anymore :( . all i remember is that it involves some kind of phone...
By: - 13th January 2005 at 12:20 Permalink - Edited 1st January 1970 at 01:00
Ok i just found one page from my Red Storm Rising book where Chicago and Boston are communicating underwater.It just mentions that they talked and that their gertrude phones were on a very low power setting.
By: - 13th January 2005 at 18:30 Permalink - Edited 1st January 1970 at 01:00
couldnt they have some sort of towed floating communication array? that would give it some sort of satellite link?
By: - 13th January 2005 at 18:53 Permalink - Edited 1st January 1970 at 01:00
Yes, they could.
A small towed floating communication array could give them GPS coordinates, satellite com, launching codes, controls for drones, missiles, UCAV-N etc..
But I would have the same negative aspect like a periscope or a snorkel.
Even if you make it stealthy, it could be seen by ships, aircrafts and satellite.
fightingirish
By: - 14th January 2005 at 13:15 Permalink - Edited 1st January 1970 at 01:00
Search for underwater telephones and read it.
By: - 14th January 2005 at 15:48 Permalink - Edited 1st January 1970 at 01:00
They have that kind of communications buoy, at least the Russia subs have it, don't have time to get you more information
By: - 14th January 2005 at 17:36 Permalink - Edited 1st January 1970 at 01:00
there's a brief description of underwater submarine communication in Clancy's Red Storm Rising, when captain Dan McCafferty ...
Clancy huh? Is he really considered to be a reliable source these days? When I read SSN during my days in Navy I had the greatest laugh of my time. What that man is producing is either propaganda or wishful thinking regarding US submarines capabilities.
regards,
Castor
By: - 16th January 2005 at 19:46 Permalink - Edited 1st January 1970 at 01:00
well not everyone has the Sea Dragon avionics suite installed on their aircraft ;)
but even then, a periscope is pretty big, but this would be some sort of tiny camoflauged thing...
By: - 16th January 2005 at 22:00 Permalink - Edited 1st January 1970 at 01:00
Since electromagnetics waves are quickly attenuated in water, how do submarines communicate when underwater, furthermore, till which depth communication with external world is possible (a few millimeters or meters).
Those guys listen for broadcasts from both shore stations and aircraft. Only generally in an emergency will they break radio silence.
Radio amateurs intercept these signals on a regular basis.
Worldwide Utility News (WUN) is an electronic club for sharing news, information and loggings about Utility (non-broadcast) transmissions on the radio spectrum.
This is the WUN clubs guid to ELF-VLF:
http://www.wunclub.com/archive/files/ELF-VLF-GUIDE-v1.0.rtf
This website should give you all the info you need. The website creator is a Norwegian radio amateur who monitors Russian naval signals:
http://www.vlf.it/zevs/zevs.htm
http://www.cvni.net/radio/nsnl/nsnl60mil.html
"Russian/CIS military stations
Flash message copied on 18.1 kHz:
"XXX XXX RDL 66983 47202 KARATAL 3250 2051 K"
http://www.cvni.net/radio/nsnl/nsnl47ms.html
"Our LF specialist, Trond, caught a number of flash messages on 18.1 kHz, 21.1 kHz, and 13852 kHz:
UUU XXX XXX M8H8 M8H8 WRNU WRNU SVQZ SVQZ 10193 KORKONT 8503 3052 K
XXX XXX RKS RKS 90250 WORSOWANIE 7967 8801 WERWEY 4647 4739 K
XXX XXX RDL RDL 02428 59742 OBSAD 5308 4731 K
UUU UUU XXX XXX RJD52 RJD52 59993 TARNOBOJKA 4712 7237 UUU XXX XXX RJD52 RJD52 59993 TARNOBOJKA 4712 7237 K"
The above intercepted messages are sent in Morse Code. The Russians are still big users of Morse. Cheap, efficient, well tried and tested. Those who have been seen images (or been inside) of Bears and Coots etc will notice the Morse Key. The Bear Js with their trailing wire antennas are also a very active part in the Russian communications structure.
TJ
By: - 24th January 2005 at 17:15 Permalink - Edited 1st January 1970 at 01:00
hmmz, still, a small buoy would work well i think..
Posts: 291
By: fft - 13th January 2005 at 07:43
Since electromagnetics waves are quickly attenuated in water, how do submarines communicate when underwater, furthermore, till which depth communication with external world is possible (a few millimeters or meters).