Ship-to-shore and ship-to-ship communication has changed dramatically over the years, yet new technology still depends on towers close to land.
Becoming common in the 1930s, the Marine Radiotelephone Service or HF ship-to-shore operates on shortwave radio frequencies. Marine radiotelephony was used extensively for communications to ships and aircraft over water. The U.S. Coast Guard still operates coastal radio stations for this purpose, according to Engineering Radio.
Now, pleasure vessels use medium frequency/high frequency Digital Selective Calling radios to communicate with other ships or the coast for safety, navigation, and weather information. Cell towers carry the signal when the boat is close to shore and a mixture of shortwave, GPS and satellite technology feeds the signal to the ship and shore as the boat is further out in the water. DSC is part of the internationally adopted Global Maritime Distress Safety System and by law, DSC functions are required in all newly manufactured VHF radios sold in the United States, according to Blue Seas.
DSC acts like the dial and bell of a telephone, allowing you to “direct dial” and “ring” other radios, or allow others to “ring” you, without having to listen to a speaker, according to the U.S. Coast Guard.
One manufacturer, Icom America, has figured out a way to make the communication addressable, so someone doesn’t need to sit by a radiotelephone; it can target specific ships with messages. The company recently asked the FCC for a waiver in order to manufacture, import, sell, and install one of its medium frequency/high frequency DSC radios. Icom told the Wireless Bureau typical users of its M802 model are smaller recreational ships. The FCC granted Icom certification for its model M802 in 2002; but the certification rules were updated and now the M802 doesn’t comply.
Icom has asked the bureau for a waiver until 2020, when it expects to have an MF/HF DSC radio that complies with the current standard. The FCC is asking for public input by June 8, on Icom’s request to docket 17-122.
May 15, 2017
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