This set of Wireless & Mobile Communications Multiple Choice Questions & Answers (MCQs) focuses on “Spread Spectrum Multiple Access”.
1. PN sequence converts _______ signal to ______ signal.
a) Narrowband, wideband
b) Wideband, narrowband
c) Unmodulated, modulated
d) Low frequency, high frequency
2. SSMA is bandwidth efficient when used with a single user.
3. SSMA uses signals which have a transmission bandwidth that is smaller than the minimum required RF bandwidth.
4. ___________ is a digital multiple access system in which carrier frequencies are varied in pseudorandom order.
5. A frequency hopped system does not provide security.
6. If the rate of change of the carrier frequency is greater than the symbol rate, then the system is referred as ___________
a) Fast frequency hopping system
b) Slow frequency hopping system
c) Time division frequency hopping system
d) Code division multiple access system
7. All users in CDMA system uses __________ carrier frequency.
8. In CDMA, symbol duration is ___________ than channel delay spread.
c) Slightly greater
d) Much less
9. ___________ problem occurs when many mobile users share the same channel.
c) Line of sight
10. ____________ arises from the fact that the spreading sequences of different users are not orthogonal.
a) Near-far problem
b) Line of sight
d) Self jamming
11. ____________ is used to improve reception by collecting time delayed versions of the required signal.
a) RAKE receiver
c) Frequency modulator
d) High pass filter