COMPUTER NETWORKS AND COMMUNICATIONS
WIRELESS COMMUNICATION TECHNOLOGIES
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Coherence time < Symbol period
|
|
|
Coherence time > Symbol period
|
|
|
Coherence time = Symbol period
|
|
|
None of the above
|
Detailed explanation-1: -Slow fading arises when the coherence time of the channel is large relative to the delay requirement of the application. In this regime, the amplitude and phase change imposed by the channel can be considered roughly constant over the period of use.
Detailed explanation-2: -Explanation: Fast fading occurs when the channel coherence time is less than the time duration of a transmission symbol.
Detailed explanation-3: -Explanation: Slow fading channel may be assumed to be static over one or several reciprocal bandwidth intervals. In the frequency domain, this implies that the Doppler spread of the channel is much less than the bandwidth of the baseband signals.
Detailed explanation-4: -Slow fading refers to changes in signal strength between a transmitter and receiver as the distance between the two changes by a larger distance, well in excess of a wavelength.