How do submerged submarines communicate?

Using frequencies from very high to extremely low, submarines can communicate by radio when submerged if certain conditions are met, and depending on whether or not detection is important. Submarines seldom transmit on long-range high-radio frequencies if detection is important, as in war. However, Super (SHF), Ultra (UHF), or Very High Frequency (VHF) two-way links with cooperating aircraft, surface ships, via satellite, or with the shore are fairly safe with high data rate, though they all require that the boat show an antenna above the water or send a buoy to the surface.

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