Submarine Matters strives to bring all manner of submarine topics to you the reader. To that end Anonymous reported on August 22 and Unknown reported August 23, 2023, on submarine reception of signals. Pete has done some English from another language editing and has also attempted more explanations of these highly technical topics, with lots of question marks ? when issues need clarification.
For the last 7 to 10 years NATO standardLink 11 due to a low data rate?deficiency has been upgraded to Link 16 [maybe a tactical version of Link 22 ?]. With Link 22 being a packet, internet protocol (IP) system in the HF and UHF radiofrequency bands. Link 22 operates in the 1 GHZ range to have broader bandwidth for higher bit rates to transmit maps and video, etc.
Link 22 allows for very small antennas (A quarterwave is about 7 cm) but at these frequencies you have to be in the line of sight and to achieve high gain using a small parabolic dish (30/40 cm?) on the surface (searching and tracking automatically the right satellite) is needed.
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France's Barracuda SSNs use Links 11, 16 and 22 via the
Thales DiveSat (see above) antennas. The German Aeromaritme company has specific radio masts probably functionally identical.
This is "passe" (designed 15/20 years
ago) however with the emergence of Phased Array matrix detectors at very low cost
(Starlink internet terminal includes a flat antenna that can scan and track satellites automatically (valued) at US$500.
"A submarine towing a flat plastic black sheet 30 cm in size on the surface..(with electronics and a power source, FO? link for the
data) Detection?..Retrofit likely." [Pete knows not what is meant by this!]
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As for buoyant wire antennas (towed by subs - see above) they are useful in the HF band, at 10/30 Mhz, for traditional radio links over long distances, up to 10,000 miles if the seasons and the ionosphere are ok
There is no need for an (indiscrete) surface wire with VLF [see NEREIDES' artwork above] because in the 3/40 KHz the Electromagnetic (EM) field penetrates down to 20 meters. Although a long surface wire is far better for reception. However the bandwidth at these frequencies is in a fraction of kbits/sec order of magnitude, less than the old traditionalanalog phone using a landline of Thomas Edison in 1890.
Pete Comment
It is always assumed that submarines merely receive messages and "never transmit" to Headquarters for instructions. This is demonstrably false.
It need be remembered that concerning the first and only time a nuclear submarine has torpedoed a ship in battle - HMS Conqueror sinking General Belgrano in 1982 - HistoryNet records:
“…Conqueror duly reported its change of direction to London at 1400 Zulu [time]. Then, despite problems with its communications equipment, at 1710 Zulu the British submarine received and acknowledged the new [Rules of Engagement] ROE and orders to attack. At the same time Cmdr. Chris Wreford-Brown, Conqueror’s captain, transmitted his intention to strike the enemy..."
Presumably HMS Conqueror used an HF, UHF or VLF? radio transmission encrypted and aimed at
a satellite for security? to report to London and to acknowledge London's orders.