P13.3 Communications Flashcards
What are carrier waves?
Waves used to carry any type of signal
Why are radio waves used instead of microwaves?
Can travel much further and do not dissipate to the surroundings as much
What are some problems of mobile phones?
It may affect your brain
Children have thinner skulls than adults
Radiation passes more easily
Therefore the brain is more exposed
How is a signal is transmitted and detected?H
The oscillator supplies carrier waves to the
transmitter in the form of an alternating current
Audio signals are supplied to the transmitter where it’s used to modulate the carrier wave
The alternating current supplied to the ariel causes it to emit radio waves that carry the audio signal
When the radio waves are absorbed by the receiver they induce an alternating current in the receiver ariel which causes oscillations
The Retriever circuit separates the audio signal from the carrier wave
The audio signal is supplied to a loudspeaker which sends out sound waves
How are carrier waves used to carry information?
By varying the amplitude
What is the advantage of using optical fibers?
More secure than radio waves and microwaves
Optical fibers carry much more information as light has a much shorter wavelength
