signals system

A common format for encoding different kinds of message signals (e.g., speech signal, video signal, computer data, etc.) for the purpose of transmissio..

Advantages - The advantages associate with digital communication systems include (i) A common format for encoding different kinds of message signals (e.g., speech signal, video signal, computer data, etc.) for the purpose of transmission. (ii) An improved sec..

The input transducer converts the message to an electrical signal say a voltage or current. Another transducer at the destination converts the output signal to the desired message for..

In earlier times, the most widely used form of communication was a system based on the transmission of a continuous-wave (CW) signal. With this system, the signal was interrupted periodically (Morse code) to produce a coded message. The CW systems r..

is contamination by extraneous signals from human sources, other transmitters, power lines and machinery, switching circuits, etc. Interference occurs most often in radio systems whose receiving antennas usually intercept several signals at the same time. Radio-freque..

refers to random and unpredictable electrical signals produced by natural processes both internal and external to the system. When such random variations are superimposed on an information-bearing signal, the message may by partially corrupted or totally obliterated. ..

It translates the sampled amplitude data into a code. The code is transmitted as a succession of pulses and spaces. The system enjoys greater freedom from noise and interfering signals than is possible with most other pulse systems. This freedom arises from the fact t..

There are digital circuits which either allow a signal to pass through or stop it. The circuits other wise called as gate allows the signal to pass only when some logical condition are satisfied. Under such condition the circuits are called logic gates. They are building b..

The ratio of change of amplitude of carrier wave to the amplitude of normal carrier wave is called the modulation factor ..