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Correct choice is (a) True

To explain I would say: Architecture of local and global memory among processors can contribute to ALGORITHM performance. Balancing high SPEED data flow and bandwidth reduction LEADS to CLUSTERING of memory and processing capacity.

The correct answer is (b) Zero crossing DETECTOR consists of a SAMPLE and HOLD circuit

The EXPLANATION: Sigma-Delta ADC does not require a sample and hold circuit. The zero-crossing detector can be implemented by threshold logic.

Correct option is (d) Diversity

To explain: Gain, NUMBER of antenna channels REQUIRED to SUPPORT multiband multimode operation, number of ADC’s and number of DAC’s are PARAMETERS influenced by antenna characteristics.

Right option is (d) three way

To explain I would say: The three way sectors are functionally DISTINCT. Each sector is assigned with SEPARATE RF CHANNELS to satisfy HIGH subscriber densities.

Correct choice is (c) Deposition of instruction mix to the new processor

The best EXPLANATION: The change INDUCED in MIPS due to re-hosting scenarios is computed by determining the instruction mix of the LIBRARY object, translating the instruction mix to the new processor, and determining DEMAND per processor to manage resource utilization. It is important to determine this parameter to compute the number of new processors required for large scale application.

Correct answer is (B) less than 0.5

Best explanation: Good performance is observed when UTILIZATION is less than 0.5. There is 50% available capacity. The unprecedented performance DEGRADATION GENERALLY causes utilization to fall in the range between 0.5 – 0.75. When utilization is greater than 0.75, the system is regarded as UNSTABLE.

Right answer is (d) QAM

For EXPLANATION: Class C operation is incompatible with amplitude sensitive modulation type such as QAM. However it does not face any COMPLICATION with amplitude insensitive modulation type such as FM.

The correct option is (d) Analog diversity

Explanation: Analog diversity combiner selects the diversity channel with MAXIMUM signal strength whereas DIGITAL diversity combiner uses TIME delay and addition of signal to YIELD signal of better strength and COHERENCE.

The correct option is (a) True

To elaborate: Radio application layer BINDS distributed objects together into waveforms. It constructs PHYSICAL and virtual radio channels from paths provided by INFRASTRUCTURE layer. The interface between radio application layer and infrastructure layer is DEFINED by CORBA IDL.

Right OPTION is (b) Waiting for timer

To explain: A state machine is any device that stores a status for a GIVEN time. The status may change according to the input. Waiting for instantiation, fetching the WAVEFORM, and waiting for response are the three STAGES of a state machine. Conditions for switching from one state to another are a part of the state machine.

The CORRECT option is (d) waveform

The explanation: The channel object may be organized as a set of SOFTWARE objects that carry out the assigned sub-system LEVEL functions of RF control, modem processing, INFOSEC, and internetworking. The channel object obtains system resources for the waveform.

Right choice is (b) Tunneling

Easiest explanation: The integration of APPLICATION Specific Integrated Circuits in SDR necessitates a means for passing control and data INFORMATION. The access of architecture level functions from COMPONENT level BUILDING blocks may be called tunneling. It requires the refinement of layered virtual machine architecture.

Right answer is (a) DATA DICTIONARY

To explain I WOULD say: SYNTAX and semantics of messages are compiled in a data dictionary. The PROPER format (syntax) and meaning (semantics) of messages are necessary for successful integration of software and hardware.

Right option is (C) complex numbers, double

To EXPLAIN: Quadrature sampling uses complex numbers to double the bandwidth AVAILABLE for a particular sampling rate. It is a polyphase filter. Real signals are combined with cosine and sine reference SIGNAL generated by a local oscillator.

The correct option is (B) Density

For explanation: In resonators with nanoscale I-beams suspended over the CAVITY, the MECHANICAL FREQUENCIES of I-beam are determined by size and stiffness of I-beam, and the distance between the beam and bottom of the cavity.

Correct CHOICE is (b) actors

The explanation is: The UML is a general purpose, modeling LANGUAGE INTENDED to PROVIDE a standard way for defining the design of a system. Abstract external objects are called actors in UML terminology. Actors have PROPERTIES and behavior that shape the system design.

The correct answer is (B) Encapsulation

Easiest explanation: The first step in the development of object oriented MODELS is the identification of object classes. This is accomplished by encapsulation. Encapsulation is assembling a cohesive SET of DATA and FUNCTIONS to define an object.

The correct option is (a) KY series

To ELABORATE: KY series in involved in analog voice encryption. KG84 introduced EXTERNALLY invoked modes for AUTHENTICATION and streaming. CYPRIS and VME are advanced INFOSEC modules.

Correct ANSWER is (C) IDENTIFICATION of processing capability

The explanation: The functions of the tunneling facility include the definition of interface points, USE of tunneled components, identification of constraints, and resolution of conflicts. The interfaces to the application objects are described to the radio infrastructure by USING Tunnel() function.

Correct answer is (d) 30 – 400 MHz

The best explanation: SPEAK easy split the operating range into three BANDS: a) 2 – 30 MHz; b) 30 – 400 MHz; and C) 400 – 2000 MHz. BAND b was achieved by SPEAK easy – 1 and band a, b was achieved by SPEAKeasy – 2.

Right answer is (c) Thread activation rate* COMPLEXITY * Sub thread load factor

Explanation: The TOTAL SOFTWARE demand is given by the product of thread activation rate, complexity, and sub thread load factor. The load factor reflects the number of times a sub thread is invoked for an incoming stimulus. The number of instructions per INVOCATION is CALLED the complexity.

Right option is (d) Creation of performance MANAGEMENT spreadsheet

Explanation: The performance management spreadsheet systematizes the description of processing demand. If processing CAPACITY is estimated EARLY in the development cycle, facility utilization can be AUTOMATICALLY estimated.

Right choice is (B) High speed interconnect

To explain: INFRASTRUCTURE layer manages the resources of the distributed MULTIPROCESSOR ENVIRONMENT. It simplifies interfaces and entities for efficient deployment. Synchronization, resource MANAGEMENT, position generation, and signal path packages are some services facilitated by infrastructure layer.

Right option is (a) True

To explain I WOULD say: The proper format (syntax) and meaning (semantics) of messages are necessary for successful integration of software and hardware. Setup and CONTROL, state and state transition, information stream with specific timing constraint, timing and FREQUENCY standard information are examples of useful messages for object INTERFACES.

Right CHOICE is (a) service

Explanation: A SEQUENCE of calls behaves as interface between service layer and radio APPLICATION layers. It sets up radio applications. It creates link for information SERVICES. It is USED for bridging in military applications.

The CORRECT ANSWER is (B) Message passing

Explanation: Message passing permits CONCEPTUAL integration of software components. It also facilitates interconnection across physical boundaries of various devices used for development such as FPGA.

Correct answer is (a) Boolean

The explanation is: Fix, floating point and DOUBLE are few types of data FORMAT extension used for REPRESENTATION of numbers. Boolean is a data type.

Right answer is (d) variance

Easiest explanation: When ZERO crossings are simply counted, a small variance of N zero crossings indicate a SIGNAL to be present. A disadvantage of this technique is the PRESENCE of HIGH speed logic and LACK of equalization.

The CORRECT choice is (C) LO leakage and DC bias

To EXPLAIN: LO leakage and DC bias are a challenge for wide BAND digital SIGNAL processing using direct conversion receiver.

Correct CHOICE is (c) Frequency hopping

To explain: Frequency hopping can provide FADE RESISTANCE for slow-moving mobiles. GSM’s frequency hopping plan improves SNR by averaging deep FADES.

Correct answer is (c) P=Pif+N*(Ps+Pbs+Pbb)+PMO

To explain: P=Pif+N*(Ps+Pbs+Pbb)+Pmo is the expression used to compute PROCESSING demand. Processing demand depends on a first-order approximation on the signal bandwidths. It is also influenced by the intricacy of the OPERATIONS in the IF, baseband, BITSTREAM, and source segments.

Right option is (a) communication services

The EXPLANATION: SEAMLESS access to FACILITIES of other layers, enhanced capability, enhanced interoperability, easy access to off-the-shelf software products and protocols are few tradeoffs seen in the communication services level of the ARCHITECTURE.

Correct option is (d) Low pass filters, MODULATORS, signal paths

Easy EXPLANATION: Low pass filters, modulators,and signal paths must be properly matched for effective representation of input signal in QUADRATURE sampling. AMPLITUDE mismatch, inconsistent time duration in filters MAY lead to degradation of complex signal.

Right OPTION is (B) False

Explanation: The useful dynamic range is given by the ratio of largest processable signal to the SMALLEST detectable signal. It is applicable for ANTENNA, RF/IF conversion, and ADC’s. Dynamic range is one of the controlling parameters in the design of software defined radio.

The correct choice is (d) resonators and capacitors

The explanation: RF INTEGRATED CIRCUITS consist of off-chip resonators, inductors, and capacitors. Each DEVICE INCREASES the production cost which is linear function of number of components.

Correct option is (b) False

Easiest explanation: Cost of production electronics is a linear function of parts count, NUMBER of ANTENNAS and related RF/IF paths.Antenna and RF SYSTEM ACCOUNTS for nearly 60% of the total cost of a radio node.

Correct answer is (d) receiver

The best I can EXPLAIN: Active CANCELLATION is the processing of introducing transmitted signal in the receiver for subtraction from the input signal. It is a PART of interference SUPPRESSION process.

Right answer is (c) Decreased bandwidth

For explanation I WOULD say: Increased instantaneous bandwidth for MULTIPATH RESOLUTION and equalization can mitigate the effect of fading. The reduction of channel symbol rate can reduce intersymbol interference. Diversity TRANSMISSION and reception, and structuring of data provide RESILIENCE against fading.

The correct choice is (a) DIVERSITY

To explain: Diversity TRANSMISSION and reception can reduce the probability of non-recoverable fade depth. It tends to choose the SIGNAL with MAXIMUM strength, improving the error floor. FEC and interleaving are useful for compensating the erasure CAUSED by fading.

Correct answer is (b) False

Easiest explanation: Identification of critical resources, CREATION of performance management SPREADSHEET, ANALYSIS of queuing implications, and analysis of variance are the four STEPS in the performance management process.

The correct answer is (b) Sub THREAD

The explanation: A thread is a complete path from event trigger to RESPONSE. A sub thread is the INTERSECTION of a thread on a processor. It may consist of a single object INVOCATION, or MULTIPLE objects may be invoked.