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Correct OPTION is (c) Fingerprint

The best I can explain: Behavioural biometrics is a SUBCLASS of biometrics involving the measurement of unique, distinctive and measurable pattern in INDIVIDUALS. Software is required for analysis. It is cost effective means to improve security.

Correct ANSWER is (d) SPATIALLY variant

For EXPLANATION: Policy driven approach allows temporal and spatially variant regulation. For example, a RADIO can automatically adapt to varying jurisdictions imposed by different countries by modifying or uploading a policy.

The correct answer is (a) definition

To elaborate: 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.

The correct answer is (d) inference capability

Best EXPLANATION: A VARIETY of policies EXISTS to accommodate and regulate various modes and environment. It is not possible to code every possibility in a radio and it becomes necessary for the radio to UNDERSTAND the POLICY. Cognitive radio must infer from policies provided they are defined using well known language framework.

Right choice is (b) False

To explain: Spectrum awareness is affected by hidden node problem. A receiver might experience interference but may be INCAPABLE of informing the cognitive radio. A cooperative approach may be USED to MITIGATE the problem but it is not a complete solution.

Right answer is (b) Biometrics

The EXPLANATION is: Biometrics involves the measurement of distinctive features to LABEL and DESCRIBE individuals. These features are EITHER physiological or behavioural. Different aspects of human PHYSIOLOGY, chemistry, and behaviour can be used for biometric authentication.

Correct ANSWER is (b) Networking capability

To elaborate: FREQUENCY hopping, link establishment, and programmable CRYPTOGRAPHY are the features available in software capable RADIO. Each higher level radio possesses these basic capabilities with additional qualities. Networking capability and multi-waveform INTEROPERABILITY are additional features exhibited by software programmable radio.

Correct option is (b) False

For explanation I would say: Radios that perceive all or part of their surrounding are CONSIDERED aware systems. For examples, a VOICE radio CAPABLE of sensing audio frequencies. Awareness extends from simple PROTOCOL decisions to controlling network for maintaining the state of awareness.

Right choice is (d) 10^-11

Explanation: ATOMIC clocks have a STABILITY of10^-11 . However they consume high power and are large in SIZE. Local oscillators have a stability of10^-6. Local oscillators drift over TIME and may RESULT in inaccuracy of about 90 ns.

Correct answer is (d) FOUR

The best explanation: GPS receiver monitors SEVERAL satellites to precisely compute the location and clock deviation. It REQUIRES at least four satellites to be present in its field of view. Three position coordinates and clock deviation from satellite time are the unknown ENTITIES to be computed.

Right option is (c) propagation delay

To elaborate: Kalman FILTER provides high resolution estimation of propagation delay from each satellite irrespective of their position. Kalman filter uses input from ground monitoring stations, space weather information, ETC. The GPS receivers can estimate time with APPROXIMATELY 340 NANOSECONDS of jitter.

Correct option is (b) Advanced SYSTEM Improvement Program

To elaborate: SINCGARS ASIP radios are software PROGRAMMABLE. They provide improved data capability. They also offer better FEC for low-speed data modes, a GPS INTERFACE, and an Internet controller. They reduce size and weight.

Correct choice is (c) policy interpretation engine

To explain I would say: A policy MAY be written by regulatory agencies or by a third PARTY which is later approved by regulatory agencies. A policy is a LEGAL operating requirement and therefore must be verified by policy EXAMINATION engine for certification.

The correct choice is (d) Frequency division multiplexing

Best explanation: Time awareness is ESSENTIAL for a radio to learn and behave. Time of the day information is used in time division multiplexing and for gating policies in and out. It is used to COMPENSATE PROPAGATION delay from satellites to GPS receiver such that there is only 340 ns jitter.

Correct answer is (a) True

Easiest explanation: An AWARE radio uses VARIOUS SENSORS to GATHER information on the environment. An RF spectrum may be SENSED to gain information on interference, channel and signals.

Correct OPTION is (c) Kalman

The best explanation: Kalman filter uses observed values and provides ACCURATE estimates of unknown variables using joint probability distribution over the variables for each TIME frame. GPS receivers INCLUDE a one pulse per SECOND signal that is Kalman filtered.

The correct answer is (d) AWARE radio

Easiest explanation: An aware radio provides quality of service measurement and channel state information in addition to the services provided by software DEFINED radio. HOWEVER it cannot modify the radio PARAMETERS according to sensor input.

The correct choice is (c) 470 – 790 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.

Right answer is (d) machine LEARNING

Best explanation: The cognition level six to eight require machine learning. It INVOLVES incorporatingfluency, adapting established plans and PROTOCOLS. Learning in cognitive radios allows autonomous UNDERSTANDING of RADIO environment.

The CORRECT choice is (d) MANAGEMENT of conflicting plans

To elaborate: NEGOTIATION capability requires the management of conflicting plans and conduction of negotiations. It is a cognition level five capability. The expected level of competency INCLUDES ONTOLOGY such as KQML and formalized knowledge.

Right OPTION is (c) Spectrum Policy Task Force

The explanation: The Spectrum Policy Task Force operates under Federal Communication Commission. Its primary goal is to evaluate policies and PROMOTE EFFECTIVE use of spectrum. It is also responsible for USING the spectrum in such a way the PUBLIC benefit is improved.

Correct answer is (B) False

The best I can explain: Continuous SPECTRUM granting beacon is a technique employed during SUBLEASING. It supports shut-down-on-command feature, and is carried out within a bounded response time. Time based granting of spectrum, and RTS-CTS inhibit send are other techniques USED for subleasing.

Right choice is (b) time difference of arrival

Explanation: Global Positioning System is a satellite BASED radio NAVIGATION system. It offers a resolution of 100m and requires unobstructed LINE of SIGHT from satellites. It uses time difference of arrival to determine geo-location of receiver.

Right choice is (c) try out

For EXPLANATION: MACHINE readable policy controlled radio allows a policy to be implemented on few RADIOS to assess the impact of the policy. If the results are undesirable, then policy can simply be eliminated. This enables quick decision MAKING.

The correct CHOICE is (d) Television WHITE Space

To explain I WOULD SAY: 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.

Right option is (c) multiple, not 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.

Right answer is (d) Radio Open Shortest PATH First

The best explanation: Clustering labels a network into cluster heads and cluster members. Radio Open Shortest Path First is used by ROUTERS of Near Term Digital Radio. ROSPF adjacencies are introduced and eliminated in ACCORDANCE to MOBILE ad-hoc network INFORMATION provided by NTDR routers.

Correct answer is (B) an administrative

The explanation is: Demand Assign Multiple ACCESS (DAMA) is related to channel and resource ALLOCATION. It can be classified based on switching technique or control schemes. It is employed in AN/WSC – 3.

The correct choice is (b) very high frequency (VHF)

For explanation: Single-Channel Ground and Airborne Radio System CONSISTS of a FAMILY of radios that operate in the very high frequency band. They use frequency modulation. The radio is MEANT for command and control signals of voice and tactical data.

Correct answer is (a) Code DIVISION Multiple Access

The explanation: Code Division Multiple Access is a CHANNEL access METHOD. It allows a USER to occupy the ALLOCATED bandwidth for an entire period. This is accomplished by spread spectrum technology where each user is provided with a spreading code for transmission.

Correct option is (c) Direct Sequence SPREAD Spectrum (DSSS)

To explain I WOULD say: The direct sequence spread spectrum is used to spread the TRANSMITTED SIGNAL over a bandwidth wider than the information bandwidth. It offers secure COMMUNICATION with reduce interference.