P1 - Data transmission Flashcards
1
Q
What are the uses of infrared radiation?
A
- thermal imaging cameras
- security alarms
- remote controls
2
Q
What is a digital signal?
A
A digital signal is a signal with only two values, on or off.
3
Q
What is an analogue signal?
A
An analogue signal is a signal with any value and is continuously variable.
4
Q
What does the height of a wave show?
A
How loud the sound was.
5
Q
What does the distance between waves show?
A
The pitch.
6
Q
What does LED stand for?
A
Light emitting diode.
7
Q
What are the advantages of digital switchover?
A
- improved signal quality
- a greater choice of programmes
- being able to interact with the programme
- information services
8
Q
What is multiplexing?
A
Multiplexing allows many different digital signals to be transmitted simultaneously.
9
Q
What does a demultiplexer do?
A
A demultiplexer separates the signal at the receiving end.
