This set of Cognitive Radio Multiple Choice Questions & Answers (MCQs) focuses on “Adaptive Radio”.
1. Which among the following is an operating parameter which cannot be adapted?
b) Instantaneous bandwidth
c) Modulation schemes
Explanation: An adaptive radio oversees its own performance and is open for modification of operating parameters. Frequency, instantaneous bandwidth, modulation schemes, error correction coding, equalizers, data rate, and transmission power are few examples of operating parameters that can be adapted.
2. ____ spread spectrum is ____ when ___ is programmed.
a) Frequency hopped, adaptive, hop
b) Frequency hopped, not adaptive, hop
c) Direct sequence, not adaptive, sequence
d) Direct sequence, adaptive, hop
Explanation: Frequency hopped spread spectrum is not adaptive when hop is programmed. However when the hop pattern is modified to mitigate collision, the frequency hopping radio can be considered as adaptive.
3. A radio that supports ____ channel bandwidths is ____
a) joint, adaptive
b) joint, not adaptive
c) multiple, not adaptive
d) multiple, adaptive
Explanation: A radio that changes instantaneous bandwidth and system timing as per the network load may be considered as adaptive. However a radio that simply supports multiple channel bandwidths is not adaptive.
4. An adaptive radio changes its intermediate frequency characteristics in accordance to ____
a) encryption method
b) enciphering method
c) network load
d) channel characteristics
Explanation: An adaptive radio is changes the operating parameters in accordance to sensor input for effective communication. Thus an adaptive radio changes its intermediate frequency characteristics in accordance to channel characteristics.
5. Which among the following exhibit some amount of adaptive quality?
a) Digital European Cordless Telephone
b) Racal 25
c) Digital Modular Radio
d) Position Location Reporting System
Explanation: Digital European Cordless Telephone finds the noise floor and interference of all available channels. The carrier frequencies are then selected based on the information obtained from sensing such that there is reduction in the amount of interference.
6. TVWS stands for ____
a) Telephone Variable White Space
b) Telephone Variable White Space
c) Television Wide Space
d) Television White Space
Explanation: Television White Space refers to the unused space found between channels actively used in UHF and VHF spectrum. The major regulatory agencies such as FCC of the US, Ofcom of the UK, and the ECC of CEPT in Europe are developing rules for unlicensed use of TV Whitespace.
7. The ECC studied the operational requirements of cognitive radio in the range ____
a) 460 – 560 MHz
b) 470 – 650 MHz
c) 470 – 790 MHz
d) 460 – 690 MHz
Explanation: The Electronics Communication Committee studied the technical and operational requirements of cognitive radio in white space of the ultra-high frequency band in the range 470-790 MHz. It acts as a foundation for regulatory activities in ECC.
8. Which among the following is not a challenge imposed by decision making in cognitive radio?
d) Wrong choices
Explanation: The first challenge for decision making is where and how the decision should be taken. The second challenge is whether the implementation must be centralized or distributed. The third challenge is the selection of decision algorithm.
9. The concrete ____ of learning process is a challenge imposed by learning in cognitive radio.
Explanation: The concrete definition of learning process, its objectives and contributions, is a challenge imposed by learning in cognitive radio. The learning mechanisms employed may be supervised or unsupervised.
10. In dynamic security implementation, there is an increase in the number of potential interaction that can lead to a violation.
Explanation: In dynamic security implementation, there is an increase in the number of potential interaction that can lead to a violation. This leads to a decrease in time and special scales of these interactions. These conditions amplify the challenges.
Sanfoundry Global Education & Learning Series – Cognitive Radio.
To practice all areas of Cognitive Radio, here is complete set of 1000+ Multiple Choice Questions and Answers.