Subsection 10 Fibre Optics Flashcards
A ‘ Remote terminal’ on a MIL-STD-1773 fibre optic network is?
The devices being controlled
A ‘ Type A ‘ fibre optic connector would be used for connections?
Not regularly disconnected
A disadvantage of a fibre optic cable is end terminals are?
Susceptible to environmental contamination
A fibre optic coupler is used to distribute the optical signal from one fibre among two or more fibres or to combine the optical signal from two or more fibres into a?
single fibre
A fibre optic ‘ T ‘ coupling is?
2 or more sources into 1 output
A fibre optic cable consists of a silica glass core with a cladding having?
A lower refractive index
A Fibre optic cable that has been fitted with too tight a bend radius will suffer from?
Attenuation and loss of signal
A Fibreoptic data bus used on an aircraft can transmit on?
Several channels at the same time
A fibreoptic cable to the LRU connector should be connected?
Very carefully to ensure alignment and reduce light loss
A fibreoptic lens type coupling with lens and integral LED compared to an end-fibre coupling is?
More efficient
A fibreoptic light source is normally a?
laser or LED
A remote terminal can be connected to a network by ?
Conventional copper cables or fibre optic cables
A remote terminal in a fibre optic network syatem requires?
A microprocessor
A semiconductor which emits photons and releases electrons when stimulated is called?
A Laser diode
A silica glass fibre optic cable is more refractive in the?
Middle
A typical fibre optic connector is?
Coupling type with lens fitted
A typical wavelength of light in an optical fibre is?
1300nm
An advantage of fibreoptic cables over conventional cable is that?
It offers greater security
Common aircraft fibreoptics use?
Modulating intensity on direct read
Continuit of a fibreoptic cable is checked by?
A calibrated light source and an opto-power meter
Fibre optic cables are immune to?
EMI
Fibre optic data is sent by?
A strobe light
Fibre optic cables use?
A refractive outer shell
Fibre optic systems can transmit data in?
Both directions at the same time
Fibreoptics relies on?
Light reflecting off cladding
For a fibroptic cable connector that is not regularly disconnected you would use?
The Butt type
For a fibreoptic to function, then the refractive index of the core must be?
Greater than for the cladding
For a fibreoptic cable system that requires frequent disconnection and reconnection of the cable, one type of connector suitable is a?
Micro lens
For high bandwidth highspeed fibreoptic transmission, what sort of cable would you use?
Singe mode
For total internal reflection to occur, the angle of incidence must be?
Greater than the critical angle
HIRF is prevented from entering a fibre optic cable by using?
An opto-isolator coupling
In fibre optic network systems, what device handles management duties such as operation. administration and maintenance?
Remote control terminal
In a fibreoptic cable, multiple data signals ?
Can be sent down it at one time
In a singe mode fobre optic cable, the diameter of the cable is dependant on?
The wavelength of the light used
In an optical fibre half duplex data transmission, data is transferred?
Both ways, one way at a time
In an optical fibre simplex data transmission, data is transferred?
In one direction only
In an optical fibre, the angle of acceptance is?
Half the cone of acceptance
In a fibreoptic cable, signals are seperated by?
An active optic filter
In fibreoptics the wave length of the light is?
More than visible light
Light transmission in a fibreoptic cable is due to?
Repeated internal reflection
Light travels along a fibre optic by?
Reflection
Most fibroptic connectors are designed so the connections can?
Not be overtightened
Optical coherant transmissions use a single mode laser with?
Send and receive opto-isolators
Optical fibre losses are due to?
Absorption, scattering and reflection
Passive sensors in fibreoptics, process the signal but?
Do not require power
Sensors in a fibroptic flight control system require?
Power for the processors
Some of the advantages of fibroptic cable over copper cables are?
Smaller in size and weight, non-conductive, higher security and higher bandwidth
The speed of light in a fibre optic cable is?
Never greater than the speed of light in free space
Star couplers are used in fibre optic systems for?
Equally distributing signals to equipment
The angle of acceptance for fibre optics is the ?
Maximum angle to accept light into the core for transmission
The angle of incidence of a beam of light in a fibreoptic cable will be?
Approximately half that of the cone
The central controlling terminal of a fibre optic network is the?
Network control terminal
The fibreoptic cable can be identified on aircraft by its jacket colour which is?
Purple
The cone of acceptance is measured between?
The longitudinal axis of the core and the outer angle
The light source used in fibreoptics is?
Lower bandwidth than visible light
The name given to the joining of two fibroptic cables by aligning them carefully and bringing them into close proximity of each other is?
End to End
The power inputs to a star coupler are?
More than two
Two connected fibre optic cable ends are parallel but not quite touching, this is called?
End fire coupling
What does a fibreoptic star connection do?
Provides direct point-to-point services to units on dedicated lines emanating from the central hub
What is the advantage of a laser diode over an LED?
Narrower bandwidth
What is the advantage of a single mode fibreoptic over ordinary wire?
Large bandwidth
What is the advantage of an ILD over an LED when used as a light source in fibre optics?
Lower frequency range
What is the main cause of attenuation in fibreoptics?
Poor termination
What is the main disadvantage of a fibre optic data bus?
Expensive to install
What kind of light is used in a fibre optic system?
Infared
What maintenance problems are associated with fibreoptics?
Kinking and contamination of connectors
When using a TDR ( time delay reflectometer ) the loss of value of the cable is shown by?
The curve on the screen
Which of the following databus specifications is suitable for fibreoptic communications on aircraft?
ARINC 664
Which of the following is an optoelectronic device?
Laser diode.
