Spectrum Sharing MCQs : This section focuses on the "Spectrum Sharing" in Cognitive Radio. These Multiple Choice Questions (MCQs) should be practiced to improve the Cognitive Radio skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
_______________ is a promising technique to enhance spectrum utilization in cognitive radio environments.
A. Spectrum mobility
B. Spectrum sharing
C. Spectrum awareness
D. None of the above
Explanation: Spectrum sharing is a promising technique to enhance spectrum utilization in cognitive radio environments.
The interference power constraint plays an important role in the spectrum sharing environment.
C. Can be true or false
D. Can not say
Explanation: True, the interference power constraint plays an important role in the spectrum sharing environment.
Which among the following is not used as an attribute for classifying spectrum sharing?
A. Spectrum allocation behaviour
C. Spectrum access technique
D. Spectrum sensing behaviour
Explanation: Based on the architecture, the spectrum sharing techniques are categorized as centralized and decentralized. Based on spectrum allocation behaviour, the techniques are categorized as cooperative and non-cooperative. Based on the spectrum access technique, the methods are categorized as overlay and underlay.
What is the basic unit of channel allocation?
A. P frame
B. Q frame
C. R frame
D. S frame
Explanation: A Q frame is the basic unit of channel allocation. When a Q frame is allocated by a base-station, the base-station can use its control and data channels for coordination and data communication between the users.
What is the parameter used to differentiate the overlay and underlay spectrum sharing technique?
A. Delay in unlicensed spectrum
B. Delay in licensed spectrum
C. Degree of interference exhibited towards primary user
D. Degree of interference exhibited towards secondary user
Explanation: The overlay and underlay spectrum sharing techniques are classified based on the amount of interference directed towards the primary users while operating in the licensed spectrum band. Overlay exhibits zero interference while the underlay technique exhibits considerable interference which is regarded as noise by primary users.
DQSDR stands for?
A. Dynamic Quality of Service Dynamic Reservation scheme
B. Distributed Quality of Service Distributed Reservation scheme
C. Distributed Quality of Set Dynamic Reservation scheme
D. Distributed Quality of Service Dynamic Reservation scheme
Explanation: In Distributed Quality of Service Dynamic Reservation scheme, a base-station competes with an interfering base-station to allocate a spectrum band that satisfies the quality of service requirements of the user application.
What type of scheme is non-cooperative intra-network spectrum sharing?
A. Spectrum centric
B. Application centric
C. Device centric
D. Access centric
Explanation: Non-cooperative intra-network spectrum sharing allocates channels depending on observed interference patterns and neighbours. The device is modified so that it can choose the channels for communication. This method exhibits poor performance when compared to cooperative schemes but the communication overhead is reduced.
The ____________ layer particularly the MAC portion is responsible for collision avoidance
B. Data Link
Explanation: The data link layer particularly the MAC portion is responsible for collision avoidance
Which among the following is not a step in spectrum sharing?
A. Spectrum sensing
B. Spectrum mobility
C. Spectrum access
D. Spectrum management
Explanation: Spectrum sharing process is integrated with spectrum sensing, spectrum allocation, spectrum access, handshake mechanism, and spectrum mobility. Thus the selection of best available spectrum, prevention of collision due to the overlapping portion of the spectrum, and seamless connection for communication regardless of the location of the user involves spectrum sharing.
The selection of a common control channel is difficult in distributed cognitive wireless networks
C. Can be true or false
D. Can not say
Explanation: True, The selection of a common control channel is difficult in centralized networks.