What is the fundamental purpose of a communication system?

To transfer information from a source to a destination.

What defines a real-time communication system?

A system that processes and transmits information with minimal delay, so the output occurs essentially simultaneously with the input.

What would happen if a communication system introduced significant processing delays?

It would no longer be considered a real-time system, as the output would not occur simultaneously with the input.

AQA A-Level Physics 7408

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Electronics

Principles of communication systems

3 things to know
Paper 3, section B

Overview

The block diagram of a real-time system, and the role of the transmitter and channel.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Process

What is a communication system for, and what makes one real-time?

Key term

What does the transmitter do, and what is the transmission channel for?

Key term

What is the role of the destination in a communication system?

Questions from this subtopic

Each one with the model answer underneath.

1
What is the fundamental purpose of a communication system?
Model answer
To transfer information from a source to a destination.
2
What defines a real-time communication system?
Model answer
A system that processes and transmits information with minimal delay, so the output occurs essentially simultaneously with the input.
3
What would happen if a communication system introduced significant processing delays?
Model answer
It would no longer be considered a real-time system, as the output would not occur simultaneously with the input.
4
In the block diagram of a real-time communication system, what is the first stage?
Model answer
The information source.
5
In the block diagram of a real-time communication system, what stage follows the information source?
Model answer
The transmitter.
6
In the block diagram of a real-time communication system, what is the central stage that connects the transmitter to the receiver?
Model answer
The transmission channel.

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