HISTORICAL PERSPECTIVE THE EVOLUTION OF MODERN ELECTRONIC COMMUNICATION
The electronic communication has undergone through a chain of dramatic developments even since the first electronic communication invented by Morse in 1838. However, it may be noted that this development became possible due to the parallel development in the field of electronic devices, circuits etc. To provide historical perspective, the important developments in the field of electronic communication are listed ahead:
Table 1.2. A Chronology of Electronic Communication
| Year | Development |
| 1800-1837 1838 1845 1864 1876 1887 1904 1920 1923 1927 1931 1934 1936 1937 1938 1948 1950 1953 1956 1958 1960 1961 1962 1962-1966 1963 1964 1965 1966-1975 1979 1988 |
Preliminary developments The invention of telegraphy The Kirchhoff’s circuit laws enunciated Maxwell’s equations predict electromagnetic radiation The invention of telephony The invention of wireless telegraphy Communication Electronics Transmission theory Invention of television Federal communications commission established Teletypewriter service initiated H.S. Black develops the negative-feedback amplifier Armstrong’s paper states the case for FM radio Pulse code modulation Radar and microwave communication Information theory and coding Time-division multiplexing applied to telephony Colour TV Standards established in United States First transoceanic states telephone cable (36 voice channels) Long-distance data transmission system developed for military purposes Maiman demonstrated the first Laser Integrated circuits go into commercial production Satellite communication begins with Telestar I High-speed digital communication Solid-state microwave oscillators Full electronic telephone switching system goes into service Mariner 1V transmits pictures from Mars to earth Wideband communication systems Intercity optical links Under sea fiber optical link |
In the field of communication engineering, we need to analyze a given signal. To do so, we have to express the signal in its frequency domain. The translation of a signal from time domain to frequency domain is obtained by using the tools such as Fourier series and Fourier transform.