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Communication system and block diagram

Short answer

A communication system transfers information from a source to a destination through a channel. The input transducer converts the message to an electrical signal; the transmitter modulates and amplifies it; the channel is the physical medium with added noise; the receiver demodulates and amplifies; and the output transducer converts it back to the original form.

Define communication system. Draw and explain the block diagram of a communication system (explain each block briefly).

A communication system is a system that transfers information (voice, data, video) from one point (source) to another point (destination) through a medium called a channel.

Block diagram

 +--------+  +--------+  +-----------+  +---------+
 |Informa-|->| Input  |->|Transmitter|->| Channel |
 |tion src|  |transd. |  |(modulator)|  |(medium) |
 +--------+  +--------+  +-----------+  +----+----+
                                    noise ->|
 +--------+  +--------+  +-----------+       v
 |Destina-|<-|Output  |<-|  Receiver |<-------+
 |tion    |  |transd. |  |(demodul.) |
 +--------+  +--------+  +-----------+

Function of each block

  1. Information source: produces the message, such as voice, music, picture or data.
  2. Input transducer: converts the message into an electrical signal, for example a microphone converts sound to a voltage.
  3. Transmitter: processes the signal for sending. It includes amplification, filtering and modulation, which shifts the signal to a high carrier frequency. The signal is then fed to the antenna or line.
  4. Channel: the physical path between transmitter and receiver. It may be wired (twisted pair, coaxial cable, optical fiber) or wireless (free space). The signal is weakened and distorted here.
  5. Noise: unwanted signals added in the channel and the equipment, which reduce the signal quality.
  6. Receiver: receives the weak signal, amplifies it, selects the wanted channel (tuning), and recovers the original message by demodulation.
  7. Output transducer: converts the electrical signal back to the original form, for example a loudspeaker.
  8. Destination: the user who receives the message.

✓ Answer checked by Claude Opus 5.5 (high effort)

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