detection

n. discovery, act of detecting, finding out; fact of being detected; demodulation, act or process of separating a modulated message from the carrier signal (Computers, Telecommunications)

In general, detection is the extraction of intelligence from a carrier signal in a communication system. Note that this may be either an overt signal, as in a conventional radio broadcast, or a covert signal, as in steganography.In opto-electronic systems, the generation of an electrical signal in response to a received optical input. For example, the optical signal received from an optical fiber is converted to an electrical signal in a detector, often by a photodiode.In radio systems, the extraction of an AM signal from its carrier frequency.
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Noun
1. the perception that something has occurred or some state exists; "early detection can often lead to a cure"
(synonym) sensing
(hypernym) perception
2. the act of detecting something; catching sight of something
(synonym) catching, espial, spying, spotting
(hypernym) discovery, find, uncovering
(derivation) detect, observe, find, discover, notice
3. the detection that a signal is being received
(synonym) signal detection
(hypernym) reception
4. a police investigation to determine the perpetrator; "detection is hard on the feet"
(synonym) detecting, detective work, sleuthing
(hypernym) police work, police investigation

n. detection

(n.)
The act of detecting; the laying open what was concealed or hidden; discovery; as, the detection of a thief; the detection of fraud, forgery, or a plot.