WorksheetsEC8071_CR_MODEL EXAM_QUIZ_V_(15.10.2020)-MORNING-PART-A
Total questions: 30
Worksheet time: 30mins
Name
Class
Date
1.
1.This function detects spectrum holes and senses the presence of the LU when the CU operates on a licensed band. Name the spectrum function?
a)
Spectrum Sharing
b)
Spectrum Sensing
c)
Spectrum Management
d)
Parameter Adjustment
2.
2.This Function is used to coordinate channel access with other users, which involves multi-user multi-address and resource allocation. <br />
a)
Spectrum Sharing
b)
Spectrum Sensing
c)
Spectrum Management
d)
Parameter Adjustment
3.
3.A cognitive radio should be designed to be aware of and sensitive to the changes in its surroundings time to time.True/False?
a)
true
b)
false
4.
4.The _______________________ is the optimal linear filter for maximizing the signal-to-noise ratio (SNR) in the presence of additive stochastic noise. <br />
a)
High pass filter
b)
Low pass filter
c)
Matched filter
d)
Mechanical Filter
5.
5.OFDM-based CR networks are known to be excellent fit for the physical architecture of CR networks. TRUE/FALSE?<br />
a)
true
b)
false
6.
6.The main issues covered in spectrum sharing include coexistence of Cognitive Users and Licensed Users and management of available non-continual bandwidths.<br />
a)
true
b)
false
7.
7.An efficient ________________ must address the sensing, access and mobility of the spectrum, which are the main functions of the cognitive cycle.<br />
a)
MAC protocol
b)
Routing Protocol
c)
Link Control Protocol
d)
Traffic Control Protocol
8.
8.Each station is represented by a ______________________temporarily storing arriving customers, while customers arrive at each station following a random process.<br />
a)
List
b)
Tree
c)
Queue
d)
Stack
9.
9. The server continuously serves a station until either the station is empty or a predetermined number of customers have been served.This type of Polling Service policy is
a)
Limited Service Polling System
b)
Exhaustive Service Polling System
c)
Gated Service Polling System
d)
Limited-1 Polling System
10.
10.In ___________________Polling Service policy,the server serves all customers in a station continuously and leaves the station only when the station buffer is empty.<br />
a)
Limited Service Polling System
b)
Exhaustive Service Polling System
c)
Gated Service Polling System
d)
Limited-1 Polling System
11.
11.With pure ALOHA, a station transmits a packet whenever it wants to. TRUE/FALSE?<br />
a)
false
b)
true
12.
12.If no acknowledgment is received by the sender in an ALOHA method, it indicates a ___________________, the frame is sent again. <br />
a)
Packet Loss
b)
Collision
c)
Packet Damage
d)
Delayed packet reception
13.
13. In ALOHA Method, the packet arrival rate at a particular station is assumed to follow ________________ distribution.
a)
erlang
b)
Gaussian
c)
Poisson
d)
Bernouli
14.
14.In Slotted ALOHA If a node sends a packet in time slot 't' and there is no other transmission during the same time slot (with duration τ ), then the________________________. <br />
a)
packet will be successfully received
b)
packet will not be successfully received
c)
packet will be received after several collision
d)
packet will be received only after a long delay
15.
15.In ____________ Multiple Access method , to avoid collision, If the channel is sensed busy, the user holds its packets until the medium is free.<br />
a)
CSMA
b)
Polling
c)
Pure ALOHA
d)
Slotted ALOHA
16.
16.InCSMA-CA,During the backoff time, the backoff timer is decreased only when the channel is idle. To ensure stability, _________________ is used for handling heavy loads. <br />
a)
Binary Exponential Backoff times
b)
Linear Backoff times
c)
Uniform Backoff times
d)
Random Backoff times
17.
17.In _________routing rotocol, route discovery is done by broadcasting a Route Request (RREQ) message on common control channel and being identified by sender and receiver IP addresses. <br />
a)
SPEAR
b)
SAMER
c)
SORP
d)
MSCRP
18.
18.__________________ is an on demand routing protocol that is neither based on centralized spectrum allocation nor multi-channel. The nature of this protocol is due to lack of shared information.
a)
SPEAR
b)
SAMER
c)
SORP
d)
MSCRP
19.
19.The successful deployment of CR networks and the realization of their benefits depend on the placement of __________________________.<br />
a)
essential security mechanisms in sufficiently robust form
b)
simple access methods
c)
easy and compatible hardware support
d)
potential breakthrough to licenced networks
20.
20. __________________, is an important attribute of CR networks which raises security issues.
a)
Spectrum Sensing
b)
Spectrum Management
c)
Parameter adjustment
d)
Coexistence
21.
21.coexistence between primary and secondary networks is known as ________________________ coexistence
a)
Incumbent Coexistence
b)
Self coexistence
c)
Intrusion Coexistence
d)
immediate Coexistence
22.
22.Secondary users are permitted to operate in licensed bands even if it creates much more interference to the incumbent users in a OSS Paradigm. TRUE/FALSE?<br />
a)
true
b)
false
23.
23.A rogue secondary user attempts to gain priority over other secondary users by transmitting signals that emulate the characteristics of the incumbent’s signals. This type of attack to CR network is known as_________________
a)
Eavesdrooping
b)
Jamming
c)
Hacking
d)
Primary User Emulation
24.
24.In the context of DSS, Byzantine failures may be caused by either malfunctioning sensing nodes or malicious nodes launching_______________ attacks
a)
Spectrum Sensing Data Falsification
b)
Primary User Emulation
c)
Intruding through Mallicious code
d)
Self Jamming
25.
25.The investigation of DSS Byzantine failures involves not only the study of data fusion techniques, but also the interplay between the data fusion techniques and the spectrum sensing techniques. VALIDATE this statement.
a)
true
b)
false
26.
26.In 802.22, the self-coexistence problem is exacerbated by having_________________________
a)
very small BS coverage area
b)
very large BS coverage range
c)
WRAN optimized to User's requirements
d)
Timing synchronisation
27.
27.An 802.22WRAN needs to acquire spectrum resources through exclusive spectrum sharing methods such as the ___________________________.
a)
On demand spectrum contention (ODSC) protocol
b)
Fixed Spectrum Occupancy protocol
c)
Leased Spectrum contention Method
d)
Limited Utilisation Methods
28.
28.Auctions are among the best-known market-based allocation mechanisms due to__________________________<br />
a)
their perceived fairness and allocation efficiency.
b)
their reliability and continued support
c)
their exclusivity and luxuriness
d)
None of the above
29.
29.In On demand Spectrum Auctions, a compact bidding language is needed to allow buyers to conveniently express their desire and do it so compactly.TRUE/FALSE?
a)
true
b)
false
30.
30.______________________ is the ability of a system to avoid total failure despite unforeseen conditions or partial damage.
a)
Reliability
b)
Robustness
c)
Reusability
d)
Security
100 %
