Name the three main transmission-path media used in communication systems.

Metal wire, optic fibre, and electromagnetic waves (radio and microwave).

What is metal wire used for as a transmission medium?

Metal wire is used to carry electrical signals along a physical conductor for communication.

What is optic fibre used for as a transmission medium?

Optic fibre transmits information as pulses of light through thin glass or plastic fibres.

Ground waves are radio waves that travel along the Earth's surface, following the curvature of the ground.

How do sky waves propagate to distant locations on Earth?

Sky waves travel upward and are refracted back toward Earth by the ionosphere.

AQA A-Level Physics 7408

Measurements and Their Errors

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Electronics

Transmission media

4 things to know
Paper 3, section B

Overview

Metal wire, optic fibre and radio, and the trade-offs of bandwidth, attenuation and interference.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Evaluation

What are the advantages and drawbacks of optic fibre against metal wire?

Process

How does wavelength affect diffraction, and how do satellites relay signals?

Evaluation

How do satellites relay signals between ground stations, why do uplinks and downlinks use different frequencies, and what is de-sensing?

Numbers

Compare the cost considerations for metal wire, optic fibre and wireless transmission

Questions from this subtopic

Each one with the model answer underneath.

1
Name the three main transmission-path media used in communication systems.
Model answer
Metal wire, optic fibre, and electromagnetic waves (radio and microwave).
2
What is metal wire used for as a transmission medium?
Model answer
Metal wire is used to carry electrical signals along a physical conductor for communication.
3
What is optic fibre used for as a transmission medium?
Model answer
Optic fibre transmits information as pulses of light through thin glass or plastic fibres.
4
What types of electromagnetic waves are used as wireless transmission media?
Model answer
Radio waves and microwaves.
5
Define ground waves.
Model answer
Ground waves are radio waves that travel along the Earth's surface, following the curvature of the ground.
6
How do sky waves propagate to distant locations on Earth?
Model answer
Sky waves travel upward and are refracted back toward Earth by the ionosphere.

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Measurements and Their Errors

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