中国不久前刚建了一个，有三个纽约那么大
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送交者: HHS 于 2023-02-08 07:48:54
回答: 现在哪还有长波电台？ 由 HHS 于 2023-02-08 07:05:07
中国不久前刚建了一个，有三个纽约那么大
Submarine communications
A ground dipole antenna used for transmitting ELF waves, similar to the U.S. Navy Clam Lake antennas, showing how it works. It functions as a huge loop antenna, with the alternating current I from the transmitter P passing through an overhead transmission line, then deep in the earth from one ground connection G to the other, then through another transmission line back to the transmitter. This creates an alternating magnetic field H which radiates ELF waves. The alternating current is shown flowing in one direction only through the loop for clarity.
Since ELF radio waves can penetrate seawater deeply, to the operating depths of submarines, a few nations have built naval ELF transmitters to communicate with their submarines while submerged. China has recently constructed the world's largest ELF facility roughly the size of New York City in order to communicate with its submarine forces without requiring them to surface.[26] The United States Navy in 1982 built the first ELF submarine communications facility, two coupled ELF transmitters at Clam Lake, Wisconsin and Republic, Michigan.[27] They were shut down in 2004. The Russian Navy operates an ELF transmitter called ZEVS (Zeus) at Murmansk on the Kola Peninsula.[28] The Indian Navy has an ELF communication facility at the INS Kattabomman naval base to communicate with its Arihant class and Akula class submarines.[13][29]
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