data transmission Flashcards
complete this sentence… infrared signals carry information that allows…
electronic and electrical devices to be controlled
how does a remote connect to the TV?
a coded signal is sent to a light emitted diode or LED at the front of the remote
what does a remote control signal include?
a start command, the instruction command, a device code and a stop command
name 3 benefits of digital signal…
- improved signal quality
- greater choice of programmes
- being able to interact with the programme
complete this sentence… optical fibres allow data to be
transmitted very quickly using pulses of light
complete this sentence… before an analogue signal is transmitted…
it is added to a carrier wave
how do remote controls work?
by emitting an infrared signal
what are infrared sensors used for?
security alarms and thermal imaging cameras
what do infrared sensors do?
detect low levels of infrared radiation from the body of an animal
what is the signal emmited by a remote control called?`
a digital signal
what does a height of a wave indicate?
loudness
what does the distance between waves indicate?
pitch. High pitched sounds have closer together waves
what does the information carried by infrared signals allow?
electronic and electrical devices to be controlled
how do they do this?
by sending a coded digital signal from a remote controller to the device. Because digital signals have only two values, any small difference in the signal value will not be noticed and can easily be removed
