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Question
Three physical media are defined in the original 802.11 standard: DSSS, FHSS, and ________.A) GFSK
B) UNNI
C) infrared
D) Barker sequence
Answer
This answer is hidden. It contains 1 characters.
Related questions
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A means of transmitting analog signals without regard to their content is ________ transmission.
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The simplest sort of signal is a ________ signal, in which the same signal pattern repeats over time.
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A) Voice
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A(n) ________ signal is a continuously varying electromagnetic wave that may be propagated over a variety of media, depending on spectrum. Examples are wire media and fiber optic cable.
A) digital
B) periodic
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A) multipoint
B) simplex
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Delay distortion occurs because the velocity of propagation of a signal through a guided medium varies with frequency.
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An analog signal can be transmitted only a limited distance before attenuation, noise, and other impairments endanger the integrityof the data.
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A familiar example of analog data is audio, which, in the form of acoustic sound waves, can be perceived directly by human beings.
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A) parallel
B) asynchronous
C) analog
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Q:
A ________ error can occur in the presence of white noise when a slight random deterioration of the signal to noise ratio is sufficient to confuse the receiver's decision of a single bit.
A) burst
B) idle
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Q:
________ is one of the most fundamental requirements in the transmission of a stream of bits from one device to another.
A) Standardization
B) Digitalization
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Q:
The ratio of data bits to total bits is called the code rate .
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In an __________ , there is a cluster of bits in which a number of errors occur, although not necessarily all of the bits in the cluster suffer an error.
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In ________ the phase of the carrier signal is shifted to represent data.
A) MFSK
B) ASK
C) FSK
D) PSK
Q:
Because of their simplicity and relatively low frequency response characteristics, ________ codes are commonly used for digital magnetic recording.
A) NRZ
B) AMI
C) VSES
D) B8ZS