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Right choice is (b) size of DATA blocks

Explanation: Interconnect efficiency is a FUNCTION of size of data blocks being transferred. Most BUSES exhibit low throughput for smaller block size. In addition to block size, features such as Direct Memory Access overhead, handshaking mechanism AFFECT the overall throughput.

The CORRECT answer is (a) DSP

Best EXPLANATION: Dedicated interconnect, wideband bus and shared MEMORY are different types of available digital-interconnect. In dedicated interconnect, the VENDOR of a board provides a SUITABLE interconnect. Shared memory reserves a block of memory for communication. The performance of shared memory can be enhanced by operating with programmable Direct Memory Access (DMA) or equivalent hardware.

Right OPTION is (a) True

To elaborate: It can be observed from the expression SNR=6.02*B+1.76+10log\((\frac{f_s}{2f_{MAX}})\), as the sampling FREQUENCY INCREASES, SNR increases. This is the principle behind Sigma-Delta ADC. The amount of oversampling is given by the RATIO of sampling frequency to Nyquist frequency.

Right option is (a) half of the LSB

To EXPLAIN: The effect of aliasing, SPURIOUS response in IF/RF PROCESSING and other noise must be less than half of the LEAST SIGNIFICANT bit of the ADC. If this condition is satisfied, then all the bits of ADC give only the useful signal power.

Right option is (b) RF MEMS

The best explanation: RF MEMS can IMPROVE the performance of the ANTENNA by INTRODUCING re-configurability. Multiband antenna, co-site INTERFERENCE, and programmability are challenges POSED by antenna.

The correct option is (a) Surface-wave

The best I can EXPLAIN: The Yagi antenna is a surface-wave antenna operating at 1 – 6 GHz range. It is used as radar feed and array. The setup of a Yagi antenna CONSISTS of a DRIVEN element, a reflector, and ONE or more DIRECTORS.

Correct option is (b) INSTRUCTION, data FORMAT

Explanation: Early DSP devices contained instruction extension and data format extension. These EXTENSIONS increase the THROUGHPUT by saving instruction CYCLES.

Correct choice is (c) Linearity, DYNAMIC range

The EXPLANATION is: Linearity and Dynamic range are the parameters that DEFINE software defined radio applications. SNR is measured to determine the dynamic range. The SNR and DNR value is computed from the ANTENNA to end user.

The correct option is (a) Pipelining

Explanation: Pipelining is a technique where MULTIPLE INSTRUCTIONS are overlapped during execution. Pipeline CONSISTS of many stages that vary from processor to processor. Pipelining increases the overall throughput of INSTRUCTION execution.

Right option is (b) twice the maximum frequency

The best explanation: The Nyquist CRITERION states that the sampling frequency of a BAND limited ANALOG waveform must be at least twice the maximum frequency component to properly reconstruct the SIGNAL. Aliasing can be overcome by meeting Nyquist criterion and USING filters.

The CORRECT CHOICE is (a) True

To explain I would SAY: The modulation of the subscriber signal and BANDWIDTH of the passband interference determine number and CHARACTERISTICS of roofing filter. The use of roofing filter establishes a noise floor and prevents dropped calls.

Correct CHOICE is (b) the difference

For explanation: The amount of active cancellation to be provided is equal to the difference between the maximum NON distorting input SIGNAL and the radiation level at the antenna. It is also given by the ratio of peak energy at the output of the RECEIVER antenna terminal to the maximum linear energy.

Correct choice is (c) roofing

To EXPLAIN: A roofing filter establishes the maximum (ROOF) and minimum (floor) linearly possible LEVEL for processing. It is ALSO REFERRED to as co-site filter.

The correct CHOICE is (c) Step ATTENUATOR

The EXPLANATION is: Each conversion stage of super heterodyne receiver has one LO, additional filters and amplifiers. Step attenuator is present after the pre-selector filters. It confines the total power at the input of first conversion stage WITHIN its linear range.

Correct answer is (b) Log-periodic and Equiangular Spiral

To elaborate: Log-periodic and Equiangular spiral antennas are FREQUENCY INDEPENDENT antennas. Log – periodic antenna operates over the range 10 MHZ – 12 GHz. Equiangular spiral operates over the range 100 MHz – 35 GHz.

The correct answer is (d) RF MEMS

To explain I WOULD say: RF access, antenna calibration, phase noise are some parameters which influence antenna TRADEOFFS. The antenna establishes the available RF band and is RESPONSIBLE for the directional PROPERTIES of the system.

The correct answer is (c) RATIO of LOWEST RF to highest RF

Best explanation: Bandwidth can be expressed as a PERCENTAGE of carrier FREQUENCY. An alternate METHOD is to take the ratio of lowest RF to highest RF over which the parameters such as VSWR are operable.

Correct option is (d) MIGRATION

Easiest explanation: Enterprise architecture promotes STANDARD classes and facilitates reusable OBJECTS. Enterprise architectures should promote migration paths among object representations. Enterprise architecture is open for alternatives to PREVENT inappropriate suppression of software definition approach.

Correct ANSWER is (c) Finite state machine

For explanation: A state machine is any device that STORES a status for a given time. It consists of a finite SET of distinct states, a set of inputs, a set of outputs, a NEXT state map and an OUTPUT map. Finite state machine can be in exactly one of a finite number of states at any given time.

Right option is (d) High dynamic range

Best explanation: SNR is AFFECTED by small signals in an environment of strong interference in spread spectrum TECHNIQUE. WIDE band channelized receiver affect SNR in Mobile Cellular applications. In spectrum analysis, SNR is INFLUENCED by high-fidelity instrumentation

The correct option is (a) input-referenced third-order intercept point

To elaborate: The increase in the third-order intermodulation product eventually results in the intersection of fundamental SIGNAL with the POWER of third-order intermodulation product. This is REFERRED as input-reference third-order intercept point (IP3). The OUTPUT power of the fundamental signal saturates before IP3.

Correct option is (c) Gate Array ASIC

To EXPLAIN: Electronically PROGRAMMABLE Analog COMPONENTS (EPACs) are also called as Field Programmable Analog Array (FPAAs). FPAAs COMBINE conventional analog circuit such as filter, amplifier with programmable interconnect.

The correct answer is (B) False

The BEST I can explain: The direct conversion RECEIVER is a HOMODYNE receiver which may use non-zero baseband center frequency.

The correct OPTION is (d) excess of bandwidth and PROGRAMMABILITY

The explanation is: Military application resort to channelized ARCHITECTURES DUE to excess of bandwidth and programmability. The channelized architectures have dedicated ANTENNA and RF conversion subsystem for each subbandof resonant antenna.

Right answer is (b) time of arrival

To EXPLAIN I would say: Time Difference of Arrival (TDOA) and CODE Division MULTIPLE Access (CDMA) continuously COMPUTE time of arrival in order to recover the direct sequence and spread spectrum waveform.

Correct answer is (a) Symbol integration

The explanation: Carrier tracking is ACHIEVED by tracker. Viterbi decoder is a maximum likelihood majority decoder. Blind EQUALIZATION is implemented by weighted TAPPED delay line filter. These functionalities are accomplished using software. Although symbol integration is REQUIRED by CDMA, it is implemented using ASIC.

Right option is (C) By including a push-down STACK with Pop() function

The EXPLANATION is: A finite state machine be converted into a push down automata by including a push-down stack with Push() and Pop() function. Push-down automata supports unlimited number of STATES. The availability of stack SPACE and time taken to reach certain states are challenges for push-down automata.

Correct option is (d) STEL-2000

The explanation: DSP cores are processors produced to be a PART of DSP ASIC device. Motorola DSP56300 is a 24 – BIT processor. TI TMS320/C54x and Motorola 56300 have 16 – bit processors.

The correct option is (d) Third-order intermodulation PRODUCT

Easy explanation: The point at which the OUTPUT noise level is tangential to the power of the third-order intermodulation product of ADC determines the spurious FREE dynamic range of ADC.

The correct option is (b) Pm=-174dBm+10log(WA)+NF

To EXPLAIN: If Wa is the receiver bandwidth and NF is the noise figure, the noise power of a noise limited receiver is given by the expression Pm=-174dBm+10log(Wa)+NF. The noise power of the noise limited receiver MUST be matched to power of the LEAST significant bit of ADC.

Right answer is (a) True

The best I can EXPLAIN: Superconducting ANALOG filters can reduce NOISE and interference introduced by wide bandwidth of SDR architecture. The combined use of superconducting filter and regular anti-aliasing filter can offer BETTER spectral purity.

The correct OPTION is (c) class C

Explanation: RF amplifiers operate in saturated MODE (class C). It non-linearly DISTORTS the waveform. Class A, class B, and class AB are linear amplifiers. The output SIGNALS are linearly related to input signals.

Right option is (b) off, INACTIVE

The best explanation: In ACTIVE blanking, COMMUNICATION between RF stage and rest of the communication SYSTEM is off while the control line is inactive. This is an EXAMPLE for active cancellation.

Right OPTION is (d) Phase interferometry

For explanation: Time-difference of arrival and angle of arrival are determined by phase interferometry. These parameters PLAY an important ROLE in network-based emitter LOCATION techniques.

The correct choice is (d) SUSPENSION

To explain I would say: Interference generates false messages and masks legitimate messages. The PERMANENT suspension of a FALSELY masked message can be prevented by techniques such as POSITIVE ACKNOWLEDGEMENT and timeout.

The CORRECT option is (d) WIRELESS Access Protocol

Easy explanation: Wireless Access Protocol is a technical standard for accessing information over a MOBILE wireless network. It is interoperable with different network technologies such as CDMA and GSM. It translates laptop level DISPLAY information to a level suitable for handheld device.

Correct choice is (a) a memory

For EXPLANATION: State machines consist of a memory that represents the number of STATES. It detects INPUT andgenerates OUTPUT as a function of state transition.

The correct option is (a) INPUT bitstream SYNCHRONIZATION

The best I can explain: The FIRST step in FEC decoding is input bitstream synchronization. It is followed by reversing the effect of SYMBOL puncturing and estimation of transmitted bits. Then the resulting signal is DECODED and descrambled.

The CORRECT OPTION is (a) TURBO codes

The explanation: Turbo codes interleave two systematic concatenated codes. It improves error PROTECTION. Turbo codes exhibit high performance with low complexity encoding and decoding ALGORITHMS.