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modulation, in communications

(Encyclopedia)CE5 Modulation modulation, in communications, process in which some characteristic of a wave (the carrier wave) is made to vary in accordance with an information-bearing signal wave (the modulatin...

modulation, in music

(Encyclopedia)modulation, in music, shift in the key center of a composition. For its accomplishment use is made of the fact that each chord figures in the harmonic relationships of several keys. In modulating from...

code, in communications

(Encyclopedia)code, in communications, set of symbols and rules for their manipulation by which the symbols can be made to carry information. By this extended definition all written and spoken languages are codes. ...

communications industry

(Encyclopedia)communications industry, broadly defined, the business of conveying information. Although communication by means of symbols and gestures dates to the beginning of human history, the term generally ref...

communications satellite

(Encyclopedia)communications satellite artificial satellite that functions as part of a global radio-communications network. Echo 1, the first communications satellite, launched in 1960, was an instrumented inflat...

data communications

(Encyclopedia)data communications, application of telecommunications technology to the problem of transmitting data, especially to, from, or between computers. In popular usage, it is said that data communications ...

frequency modulation

(Encyclopedia)frequency modulation: see modulation; radio. ...

amplitude modulation

(Encyclopedia)amplitude modulation: see modulation; radio. ...

phase modulation

(Encyclopedia)phase modulation: see modulation. ...

Communications Satellite Corporation

(Encyclopedia)Communications Satellite Corporation (Comsat), organization incorporated (1962) by an act of Congress to establish a commercial system of international communications using artificial satellites. Alth...