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Although development of the first radio wave communication system is attributed to Guglielmo Marconi, his was just the practical application of 80 years of scientific advancement in the field including the predictions of Michael Faraday, the theoretical work of James Clerk Maxwell, and the experimental demonstrations of Heinrich Rudolf Hertz. [1]
The Evolution of Media, 2007, Rowman & Littlefield; Poe, Marshall T. A History of Communications: Media and Society From the Evolution of Speech to the Internet (Cambridge University Press; 2011) 352 pages; Documents how successive forms of communication are embraced and, in turn, foment change in social institutions. Wheen, Andrew.
Human communication was initiated with the origin of speech approximately 100,000 BCE. [1] Symbols were developed about 30,000 years ago. The imperfection of speech allowed easier dissemination of ideas and eventually resulted in the creation of new forms of communication, improving both the range at which people could communicate and the longevity of the information.
The word radio is derived from the Latin word radius, meaning "spoke of a wheel, beam of light, ray".It was first applied to communications in 1881 when, at the suggestion of French scientist Ernest Mercadier [], Alexander Graham Bell adopted radiophone (meaning "radiated sound") as an alternate name for his photophone optical transmission system.
To ensure safety, the Wireless Ship Act of 1910 marks the first time the U.S. government implies regulations on radio systems on ships. [87] This act requires ships to have a radio system with a professional operator if they want to travel more than 200 miles offshore or have more than 50 people on board.
Before the discovery of electromagnetic waves and the development of radio communication, there were many wireless telegraph systems proposed and tested. [4] In April 1872 William Henry Ward received U.S. patent 126,356 for a wireless telegraphy system where he theorized that convection currents in the atmosphere could carry signals like a telegraph wire. [5]
Having heard the signal, it is easy to identify the sonar equipment used (usually with its frequency) and its position (with the sound wave's energy). Active sonar is similar to radar in that, while it allows detection of targets at a certain range, it also enables the emitter to be detected at a far greater range, which is undesirable.
Within 10 years, the device was used in radio transmitters and receivers as well as systems for long distance telephone calls. The invention of the triode amplifier, generator, and detector made audio communication by radio practical. (Reginald Fessenden's 1906 transmissions used an electro-mechanical alternator.)