28 November 2013

History of Telecommunications

By Teresa Meek

When did telecommunications begin?

It depends on what you mean by tele, the Greek word for long distance, and communications, which can take many forms.

The ancient Greeks used signal fires in their armies and sent out carrier pigeons to transmit the results of their Olympics.

Much later, in 1791, Claude and Ignace Chappe, a pair of French brothers attending separate schools close enough to be visible to each other, created a large mechanical device with arm-like rods that they manipulated to communicate with each other. Somehow, they were not expelled, and went on to help France develop over 500 of these semaphore message-relay systems, which Napoleon used to coordinate his military campaigns.

Semaphore systems, many of them using flags instead of metal arms, developed all over Europe and parts of the U.S. and were a major form of government communications systems.

When we think of modern telecommunications, however, most of us think of electricity.

People noticed early on that metals were magnetic. In the 1700’s, Henry Cavendish and others discovered that this meant they carried an electrical charge.

Electrical impulses were very interesting to scientists because of their lightning speed. (In fact, Benjamin Franklin later demonstrated in his famous kite experiment that lightning is electricity.)

Intrigued by the transmission possibilities, a French scientist in 1746 somehow talked 200 monks into standing in a very large circle, connected together by pieces of iron wire. He then used leyden jars—early forms of capacitors, which store and release current—to send out a current and measure its speed. He was pleased to note that all the monks reacted at the same time to the electric shock that resulted.

Proving that electricity does indeed travel fast—and perhaps also that monks are indeed protected by God, as none of them are reported to have died.

In the 1800s, electricity was used to create the electric telegraph, developed most successfully in the U.S. by Samuel Morse, famous for inventing the code that went along with it. With a telegraph, an operator sets up an electrical contact using a telegraph key, producing a signal that is heard at the receiving end, where another operator decodes it.

It worked great until 1876, when Alexander Graham Bell supplanted it with the telephone, which lets you hear the message voice-to-voice, with no coding and decoding involved.

Telegraph companies, however, were not impressed. The Telegraph Company had its investigators look into the new technology and write up a report, which said: We found that the voice is very weak and indistinct, and grows even weaker when long wires are used between the transmitter and receiver. Technically, we do not see that this device will be ever capable of sending recognizable speech over a distance of several miles.

Messer Hubbard and Bell want to install one of their "telephone devices" in every city. The idea is idiotic on the face of it.

But voice transmission grew stronger and better, eventually retiring the telegraph to the world’s museums.

Businesses became big users of the telephone, and some of them wondered if it could be possible to connect more than two users and exchange information without holding a physical meeting.

To attempt to meet that need, Bell Labs invented the first conference call system in 1956, and from its research, AT&T developed the Picturephone, introduced at the New York World’s Fair in 1964.

The Picturephone sent both visual and audio information across three phone lines. It was very advanced for its time, but complicated and expensive. And only three people could participate. AT&T eventually abandoned the product, after sinking a billion dollars into its investment.

Later, other businesses entered the field. Conference Calls Unlimited, formed in 1998, was one of the first to become widely successful, and is still in business today.

The next big milestone was the internet, which began as a project of the U.S. Army’s Advanced Projects Research Agency (ARPA). Then Leonard Kleinrock at MIT published papers and books pointing the way toward computer networking.

Internet protocol was standardized in 1982, and computers began to spread at universities and colleges. In 1995, the internet was allowed to be commercialized, and began its journey to becoming the behemoth it is today.