Information Theory
The "Mathematical Theory of Communications" written by Claude Shannon nearly 50 years ago in the Bell System Technical Journal has pioneered the way to Information Theory. Shannon identified problems that could be solved with a different communications system than the world was used to. Communication methods have come along way. In Eygptian times, stories and history were painted on rocks in hidden temples. As communication methods grew more sophisticated, the written and spoken languages were the sole methods of communicating. Today, there is a much more greater form of communication that involves digital signals at rates faster than the speed of light.The innovation of transmission of signals at billions of bits per second was invented by Bell Labs mathematician Claude Shannon. This innovative breakthrough led to the notion of his large contribution to the "Information Age". Shannon identified Information as "critical relationships among the elements of a communication system". The communication system involves power at the source of the signal, bandwidth/frequency range of an information channel which the signal travels, and noise of the channel.Channels can have different means of communication paths. For instance, in telecommunications the channel is represented by a wire or fiber. The new generation of wireless represents a channel through the radiospectrum used to transmit data in "free space". Shannon sought out a efficient way to communicate with these systems. Math and engineering are two major components that are represented in these information theory equations. In his findings, Shannon explains the characteristics of data compression and proved how errors in transmission of information could be controlled.
Capacity in these communication systems have also grown over time. In 1948 the largest communications cables carried 1800 voice coversations. Today, an optical fiber, which is about as thin as a human hair, can carry over 6.4 million conversations. Another example of today's growth in communication systems is that transmission of 90,000 encyclopedias can be done in just one second. Surprisingly, these rates can grow even more. The theoretical limits that Shannon laid a foundation for might transmit up to 100 quadrillion conversations, each encoded at 64,000 bits per second. The first process of encoding require symbols to be put in place for a word or phrase so that the symbol can be represented by some mathematical number, such as bits. Once the source information is compressed, transmission must take place through a defined channel with a certain capacity. Noise and interference have to be computed through the transmission state. Repetition is used to combat noise to get a smaller probability of error.
Understanding the works of Shannon's information theory is quite challenging. The elements for this theory contain source--encoder--channel--decoder--destination model. Shannon's theory takes each of these elements and replaces them with a highly mathematical model that describes its behavior within the system. From the beginning of this new found interpretation of communication, every known scientist, engineer, and information technologist has used Shannon’s theory for expanding the realms of information technology by using the theory’s template to apply to their own interest. The inventions and finding that have come from people who have used this theory are astounding. There are minimal limits to what one can do with the information theory. Each day that capacity of information is improved is another day of thanks to Shannon’s contribution to information and communication theories.