Herwin Gunawan Work

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Wireless Communication Technology from Electromagnetism Theory

With the publication of “A Dynamical Theory of Electromagnetic Field" in 1865, Maxwell demonstrated that electric and magnetic fields travel through space as electromagnetic waves moving at the speed of light. James Clerk Maxwell was a Scottish scientist in the field of mathematics and mathematical physics. Maxwell’s theory and equation about Electromagnetic have been called the "second great unification in physics” where the first one had been realized by Isaac Newton.

In 1885, Heinrich Rudolf Hertz, a German physicist was the first one who conclusively proved the existence of the electromagnetic wave which was theorized by James Clerk Maxwell 20 years back. Hertz also well known as the frequency unit (cycles per second) in honoring his work.

After success with his innovation of Alternating Current Power House, Nikola Tesla has a dream that people can communicate in real-time wirelessly from one part of the earth to the opposite part through electromagnetic waves. To realize his dream he built an experimental wireless tower in Shoreham, New York. The test facility was intended to be a transatlantic radiotelegraphy station and wireless power transmitter but was never completed due to funding drying up.

In the year 1900, Tesla claimed that there would be the precise wireless transmission of signals that would be received by devices no larger than a watch.

Tesla's Wardenclyffe wireless station, located in Shoreham, New York, was seen in 1904. Source: Wikimedia

A person who actually succeeds in making an engineering and commercial success of radio by innovating the work of Maxwell’s theory and Hertz experiment is Guglielmo Marconi. This was not a new idea; numerous investigators and inventors had been exploring wireless telegraph technologies and even building systems using electric conduction, electromagnetic induction, and optical (light) signaling for over 50 years, but none had proven technically and commercially successful.

Supported by his father, Marconi continued to read through the literature and picked up on the ideas of physicists who were experimenting with radio waves. Finally, In December 1894, Marconi demonstrated a radio transmitter and receiver to his mother, a set-up that made a bell ring on the other side of the room by pushing a telegraphic button on a bench. The role played by Marconi Co. wireless in maritime rescues raised public awareness of the value of radio and brought fame to Marconi, particularly the sinking of the RMS Titanic on 15 April 1912 and the RMS Lusitania on 7 May 1915.

After many reports began to appear about the success Guglielmo Marconi was having in developing a practical system of transmitting and receiving radio signals, then commonly known as "wireless telegraphy". Reginald Fessenden has no electricity knowledge but has a passion to become an electricity inventor. With help from an ex-assistant tester for Edison Machine Works, began limited radio experimentation and soon came to the conclusion that he could develop a far more efficient system than the spark-gap transmitter and coherer-receiver which had been created by Oliver Lodge and Marconi.

By 1899 he was able to send radiotelegraph messages between Pittsburgh and Allegheny City, using a receiver of his own design. In 1928, as part of a lecture reviewing "The Early History of Radio in the United States", H. P. Davis, commenting on entertainment offerings, asserted that "Reginald Fessenden, probably the first to attempt this, broadcast a program Christmas Eve 1906".

Nowadays, along with the development of audiovisual and digital technology, we know many wireless telecommunication and broadcast systems such as radio, television, and mobile phone. Thanks to James Clerk Maxwell a man who introduced his first theory of electromagnetism.