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The CORRECT answer is (a) True

Easiest explanation: Cohesion is the relationship among elements within a module. In incidental cohesion, functions share LITTLE relationship with each other. It is the LOOSEST form of COUPLING. FUNCTIONAL cohesion is the tightest form of coupling.

Right option is (c) Python

Explanation: GNU RADIO is a Python BASED architecture. It is designed to RUN on computers with Linux operating system. It can be used as external RF hardware to DEVELOP software radios and has SEVERAL signal processing components.

Right option is (b) synthesizes

Explanation: The circuits of TRANSMIT MODE in RF front END synthesizes RF signal. The generated signal MUST not introduce disturbance at any other frequencies and affect other users of the spectrum.

The correct OPTION is (a) True

For explanation: A PARTITION should ENSURE clear matching of functions to COMPONENTS. The physical interfaces among components must correspond to logical interfaces among functions.

The correct option is (C) USE CASE view

For explanation: The logical view defines object, classes, and interfaces. The component view is responsible for partitioning functionality. Use case view describes the BEHAVIOUR of a system in terms of relationship with external factors. The deployment view defines the relationship of components with physical ENTITIES.

Correct choice is (C) heterogeneous, distributed

Easy explanation: SOFTWARE COMMUNICATION architecture is a COMPLEX architecture that provides support for secure SIGNAL processing applications that run on heterogeneous and distributed hardware. It was developed under Joint Tactical Radio System program.

The CORRECT option is (a) True

The best I can explain: In ad-hoc networking, the reception and re-transmission of signal at each NODE introduces an overall non-uniform delay. THUS ad hoc network introduces jitter in packet delivery and is compensated by USING jitter BUFFER.

The CORRECT option is (c) discrete-time point operation

Explanation: Digital translation of a BASEBAND signal into an IF is an example for Discrete-time point operation. Discrete-time point operation involves the multiplication of discrete time-domain baseband WAVEFORM by a discrete reference CARRIER to GIVE sampled in-phase IF waveform.

Right answer is (a) channel state machine

Explanation: Network OPERATOR can identify PROBLEM areas by monitoring the progress of channel state machine. For example, when the number of HANDOFF failures increases in a cell site, it indicates the need for a gap filter or improved handoff TECHNIQUES.

Correct choice is (a) set, subsets

For explanation: A process may not have a VECTOR space that maps control STATE to a software process. Such a process has a point set topology. The subset includes process over which the software operations are VALID.

Right choice is (b) MAINTAIN consistent interfaces

Easiest explanation: Common Object REQUEST Broker Architecture is used to maintain consistent interfaces. Remote procedure calls can be MADE as if the data resides on local memory even if the data actually resides on a remote COMPUTER.

Correct option is (c) Management of thread

Explanation: Software communication architecture is a component BASED management architecture. The infrastructure provides the facility to create, INSTALL, manage, and de-install WAVEFORMS for a component. It provides control of hardware and supports communication with EXTERNAL services via interfaces.

Correct answer is (c) COMPONENT based programming

To explain: Component based programming is an extension of OBJECT oriented programming. Component based programming is preferred for SDR design as the FUNCTIONAL blocks of RADIO system can be easily represented USING separate components.

Right option is (d) IP addressing

For explanation: Media ACCESS Control processing includes FRAMING INFORMATION, frame synchronization, error detection, MAC addressing, link management, and payload ENCAPSULATION. The output of this stage is in the form of bits.

The correct choice is (b) Surface acoustic WAVE

The best EXPLANATION: Full duplex means TRANSMISSION and reception will be carried out SIMULTANEOUSLY. Bulk acoustic wave filters, Surface acoustic wave filters, Yttrium-Iron-Garnet circulators are COMPLEX structures used to aid full duplex communication.

The correct choice is (C) Power AMPLIFIER

For EXPLANATION: The RF front-end section in receive mode consists of antenna-matching unit, low noise amplifiers, filters, local OSCILLATORS, and analog to digital converters. The power amplifier is a PART of RF front-end section in transmit mode.

Right choice is (b) RF Access

The best explanation: Efficiency of spatial use is estimated by link budget. The efficiency of spectrum usage can be computed from frequency band, modulation TYPE, and bandwidth of air interface mode. NOISE FIGURE and RANGE variations are also included in the computation of link budget.

The correct choice is (d) 2^2^x-2

The best I can explain: The number of possible subsets of a power set ORIGINATING from a set with X number of element is given by the expression 2^2^x-2. This expressed is referred as double EXPONENTIAL. It is not possible for all CANDIDATE topologies to be closed under union and finite INTERSECTION. It is necessary to define finite interface topologies more compactly.

Correct option is (C) four

To explain I WOULD say: The software communication architecture is partitioned into four parts NAMELY the framework, the profiles, the API, and the waveforms. The framework is further partitioned into three parts namely base COMPONENTS, framework control, and services.

The correct answer is (B) Source authentication

For explanation: Integrity authentication verifies the reliability of DATA. Source authentication is USED to identify the creator of INFORMATION. Digital signature and key agreement techniques are examples of authentication services.

The correct CHOICE is (a) DSP

Easiest explanation: The application processer usually runs voice coder, video coder, data coder, and web browser FUNCTIONS. Speech and video applications run on DSP processor. Text and web browsing run on GPP processor.

The CORRECT choice is (B) Air interface modes

Easy explanation: System analysis, re-hosting EXISTING software on new hardware, and ADVANCED signal PROCESSING are properties of offline software support. It is achieved by prototyping and linking with channel processing streams. It also allows debugging of algorithms.

Correct answer is (c) Network SUPPORT

For explanation: The sources, which are physically REMOTE from the radio node, are CONNECTED VIA Synchronous Digital Hierarchy, Local Area Network or other networks to the radio node by service and network support.

Right answer is (a) COMPOSITION

For explanation: Composition is the point wise APPLICATION of one function to the result of another to PRODUCE a THIRD function. A set is closed under composition of functions.

The CORRECT option is (a) True

To EXPLAIN I would say: Partial FUNCTION does not require EVERY element of X to be mapped to some element of y. An example for partial function is the mapping of natural logarithm function to real numbers.

Right OPTION is (d) Common terminology

For EXPLANATION: Design patterns are programming METHODOLOGIES. Code reuse and common terminology are the major advantages of using design pattern. The use of common terminology creates better UNDERSTANDING among TEAM members.

The correct answer is (c) digital interfaces

Easiest EXPLANATION: The EXTERNAL RF components must be provided with digital interfaces for effective CONTROL of tuning FREQUENCY, transmit/receive MODE, VSWR, transmit power level sensing and gain control.

Correct option is (c) end-to-end

The explanation is: The network PROCESSING LAYER is preceded by medium access control. The input to network processing layer is in the form of bits. The network processing layer is designed with end-to-end CONNECTIVITY SUPPORT and its OUTPUT is transferred to the application layer.

Right option is (b) SYMBOLS, bits, symbol

The explanation is: The symbols, obtained from down CONVERSION process, are converted to bits by symbol detector/demodulation combination. Matched filter is an EXAMPLE for a detector.

The CORRECT choice is (a) INFOSEC

The best explanation: Information security OPERATIONS such as authentication and stream ENCIPHERING ensure DATA integrity. Further, authentication reduces fraud and stream enciphering assures privacy.

Correct choice is (b) Module composition

Easiest explanation: Module composition must preserve radio service-defining properties of the SYSTEM. It prevents erroneous RESULTS from being generated on control commands. It ALSO ENSURES proper consumption of computational resources.

The correct option is (b) QUALITY of service contracts

Explanation: Quality of service contracts were FORMALIZED in asynchronous transfer mode networks. The ATM access PROTOCOLS determine the quality of end to end connections to be offered by a network. These networks add bit errors and delay packets to accomplish their service.

Correct answer is (d) baud RATE

To explain I WOULD say: Baud rate gives the rate at which information is SENT in a communication channel. The number of TIMES an electronic signal changes state is MEASURED by baud rate.

Right option is (a) True

The best I can explain: Each time the transceiver changes frequency, the ANTENNA tuner will need to be informed of the new frequency. The antenna tunermay SENSE VSWR and adjust the tuning ELEMENTS to minimize VSWR.

The correct answer is (b) False

To explain: DIGITAL-ACCESS bandwidth is APPROXIMATELY half of the sampling RATE of the ADC in the isochronous subscriber signal-processing path. Digital access bandwidth and degree of flexibility are two important parameters of a software defined radio.

Correct CHOICE is (d) Evolution support

Explanation: Evolution support is essential to ensure that the required resources do not exceed the AVAILABLE resources of a radio platform. It monitors the definition and download process of waveform personalities. It also VERIFIES WHETHER a personality is SAFE for activation.

The correct answer is (d) query

Easy explanation: The Property Set class facilitates other class to CONFIGURE and query the RESOURCE class values by PROVIDING a set of interfaces. During run time, QUERYING can be performed by query() INTERFACE and reconfiguration can be performed by configure() interface.

Right choice is (C) Class variables

To elaborate: Class variables belong to a class and EXIST as a single copy. Instance variables belong to INDIVIDUAL objects. Instance variables exists as many copies. Each copy is paired with a separate OBJECT. Member variables INCLUDE class variables and instance variables.

Correct choice is (B) False

Explanation: GNU radio does not support distributed COMPUTING. The implementations are LIMITED to a SINGLE processor and therefore do not support high BANDWIDTH protocols.

The correct option is (C) radiated power, antenna gain

To EXPLAIN I would say: TRANSMITTER determines radiated power and antenna gain. Receiver determines receiver antenna gain and receiver sensitivity. These PARAMETERS determine the quality of received signal as PER link budget equation.

Right choice is (d) multiplication and accumulation

The explanation: The DSP INTERNAL ARCHITECTURE is optimized to PERFORM multiplication and accumulation quickly. This is done with the help of one or more multiplier and one or more accumulators. The memory structure is designed to fetch operands and INSTRUCTIONS in parallel.

Right option is (b) BOUNDED

Explanation: Software defined radio has two constraints to CONSIDER during execution namely bounded usage of resources WITHIN a module or acceptable usage of COMPUTATIONAL resources and TIMING constraints.

Right option is (a) General Purpose Processor

To EXPLAIN I would say: PowerPC is a general purpose processor. It is GENERALLY programmed using STANDARD C or C++. It provides different types of ADDRESSING modes, floating point and integration computation, large MEMORY, and on and off chip cache memory.

Right answer is (c) REUSE of design modules

For explanation I WOULD say: Increased flexibility and interoperability, reduction of supportability and OPERATION cost and easy technology insertion are some of the goals of Joint Tactical Radio System. Reuse of design modules is an optimization technique adapted to ACHIEVE the GOAL of JTRS.

Correct CHOICE is (c) Resource

Easy explanation: Resource class has only two member methods NAMELY start() and stop() and one attribute namely the identifier. It inherits from Property Set class, Lifecycle class, Port SUPPLIER class, and Testable OBJECT class to offer FUNCTIONALITIES such as initialization of a component into the framework.