Extinction Ratio
The ratio of two optical power levels of a digital signal generated by an
optical source. P
1
is the optical power level generated when the light source is
high, and P
2
is the power level generated when the light source is low.
FEC: Forward Error Correction
Additional bits and/or coding added to a data stream to allow for automatic
error detection and correction at the receiving end. These extra bits and/or
coding tend to increase a serial data rate above the original nonFEC data
stream to accommodate the extra information added by the FEC.
Fiber Optics
A method of transmitting information in which light is modulated and
transmitted over high-purity,
fi
laments of glass. The bandwidth of
fi
ber optic
cable is much greater than that of copper wire.
Impedance
The opposition to an AC signal in the wire. Impedance is very much like
resistance to a DC signal in a DC circuit. Impedance is made up of resistance,
inductive, and capacitive reactance.
Initialize
Setting the instrument main instrument to a completely known, default
condition.
Internal Clock
An internally generated trigger source that is synchronized with the Internal
Clock Output signal.
Mode
A stable condition of oscillation in a laser. A laser can operate in one mode
(single mode) or in many modes (multimode).
Modulation
A process whereby a signal is transformed from its original form into a
signal that is more suitable for transmission over the medium between the
transmitter and the receiver.
80C12B Optical Sampling Module User Manual
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