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Correct option is (b) THREAD complexity

The explanation: The number of instructions per INVOCATION is CALLED the execution complexity, thread complexity, sub thread complexity, or just the complexity. The PRODUCT of processor MIPS and processor fraction divided by invocation rate yields equivalent instructions per invocation.

Correct choice is (a) Isochronous

To elaborate: Signal flow is an isochronous stream. Isochronous thread must be completed within a short window. Isochronous threads tend to be CLASSES with timing CONSTRAINTS especially in MULTIPLE INHERITANCE object oriented environment.

Right choice is (d) THREAD

For explanation: Each EVENT might invoke more than one system response. A comprehensive COLLECTION of events is called an event-response list. A trace of the path created by stimulus-response event pair is called thread. For example, if caller and respondent are objects, then a trace would CONTAIN the caller, handset, MTSO, PTSN, and the respondent.

Correct option is (b) two way key

For explanation I would say: The Clipper Chip Key users are BOUND to provide their CRYPTOGRAPHY keys in escrow to the government. Two government agencies HOLD a PORTION of the key. The information is decrypted for investigation by the governmentonly UPON the agreement of two government agencies.

The correct option is (b) 10 MHz – 100 MHz

The EXPLANATION is: The sampling rate of promising SDR technology ranges between 10 MHz – 100 MHz. The resolution falls in the RANGE of 30 dB– 60 dB. FREQUENCY division multiplexing uses few MHz IF-bandwidth. PCM, cellular band allocation, 3G, and AIR navigation signals use hundreds of MHz.

The CORRECT answer is (b) MOPS

The EXPLANATION is: Millions of operation per second (MOPS) is obtained by the product of number of parallel hardware elements and CLOCK speed. An operation (OP) is a logical transformation of data carried out by portion of hardware in ONE clock cycle.

Right option is (C) SNR, SFDR, NPR

To EXPLAIN I would say: Spread spectrum USES SNR, SFDR and NPR for performance analysis. SNR is affected by small signals in an environment of strong interference. SFDR is degraded due to spatial filtering. NPR is affected by inter-channel cross talk.

The correct option is (a) digital filter

Easy explanation: RF ADC has a high sampling rate and it oversamples the bandwidth of the SIGNAL. The OVERSAMPLING gain increases the dynamic range with the HELP of digital integrating filters.

Correct option is (c) Matching of passive component on IC substrate is difficult

The explanation: The INTEGRATED CIRCUIT implementation of QUADRATURE sampling ADC is effective because of short signal paths, easy matching of passive components on IC substrate and low THERMAL DIFFERENCE among filters.

Correct answer is (d) convolution

The best EXPLANATION: The convolution of out-of-band SIGNAL with bandpass CHARACTERISTIC of the receiver gives the interference in the receiver owing to out-of-band energy at the transmitter.This type of interference can AFFECT the roll-offs. Frequency separation is employed to SUPPRESS this type of interference.

Correct choice is (c) self-generated interference

The explanation is: ANTENNAS in same enclosure or when CLOSELY spaced OFTEN lead to interference. This can be mitigated by ANTENNA separation. The benefit of separation can be ESTIMATED by link-based spreadsheet.

The correct choice is (c) boot-up

To EXPLAIN I WOULD say: Message processing, managing protocol stacks and internetworking are examples of back-end objects. SYSTEM control handles system boot-up, INITIAL time of day, current hop, etc.

The correct CHOICE is (a) True

Explanation: Common Broker Request Architecture was developed by Object MANAGEMENT Group. It FACILITATES communication between devices REGARDLESS of underlying hardware and DIFFERENT programming languages being used.

The correct OPTION is (b) Database algorithm

Explanation: Field Programmable Gate ARRAY is SUITABLE for algorithms having limited data SCOPE such as Fast Fourier Transform and digital filtering. However degradation of performance occurs when -FPGA is used for algorithms operating on BULK data such as database algorithms.

Correct ANSWER is (b) False

Explanation: The SNR and DNR can be determined by MATCHING the radio noise floor to the ADC input noise LEVEL. This imposes the design rule that the total noise POWER should be less than half of the least significant bit of ADC. The ratio of spectral density outside the notch filter to the maximum spectral density inside the notch filter gives the Noise Power Ratio.

Right OPTION is (B) DESIRED signal bandwidth is APPROXIMATELY equal to Nyquist bandwidth

The best explanation: Signal to noise ratio is the preferred metric for ADC performance when the desired signal bandwidth is approximately equal to Nyquist bandwidth. Radar matched filter is an example for this CONDITION. The matched filter optimally operates with the square shape of the radar pulses.

Correct choice is (c) MULTIPLEXER

Easiest EXPLANATION: The traditional RF SUBSYSTEMS comprise of preamplifier, low noise amplifier, filters, RF distribution, frequency translation, and filtering stages that convert RF signals to IF signals. Multiplexer is used in DIGITAL RF systems.

The CORRECT answer is (b) R1C0

Explanation: The industry STANDARD FIGURE of merit for an RF SWITCH is R1C0. It is given by the product of ON-resistance and OFF-capacitance. It is measured in femtoseconds.

Right option is (a) Rigidity

Best explanation: Resonator achieves sharp resonance by using BULK, acoustic and piezoelectric effects. By ADAPTING the MENTIONED effects, quality FACTOR in the range of 10,000 can be achieved.

The CORRECT option is (a) Frequency Division DUPLEXING

Easy EXPLANATION: Frequency Division Duplexing separates uplink and DOWNLINK to minimize interference. SDR operating on TDD can create dynamic FDD nets by a protocol that dynamically defines uplink, downlink and frequency separation.

The CORRECT choice is (B) increase linearly

The BEST I can explain: WIDER bandwidth results in increase of noise which REDUCES the value of SNR, affecting the performance negatively. Filtering of antenna channels according to subscriber signals can give better performance.

Correct option is (a) 2 MHZ to 2000 MHz

The explanation is: The RF range of 2 MHz to 2000 MHz was aimed to be ACHIEVED by SPEAKEASY. This FALLS in the range of 1000:1, it spans over 3 decades.

The CORRECT choice is (c) response time

Explanation: The response time is the sum of the time delays experienced in each processor that supports the thread. The resource management spreadsheet computes these sums for all THREADS DEFINED in the system. The traces of the thread over the NETWORK are used to verify the ACCURACY of the calculation.

The correct choice is (a) OFFERED demand, effective capacity

The explanation: Resource utilization relates PROCESSING demand to processing capacity. It is given by the RATIO of average offered demand to average effective capacity. It can be ESTIMATED for buses, CPUs, STORAGE devices, I/O devices, and DSP chips.

Correct answer is (B) Bus host

The explanation: Bus host serves as a SYSTEM control PROCESSOR. Analog to Digital Converter is responsible for the conversion of an analog signal into a digital signal suitable for further PROCESSING. Digital Signal Processor SUPPORTS real time channel processing.

Right choice is (b) Spurious FREE Dynamic Range (SFDR)

Easiest explanation: Spurious Free Dynamic Range is the preferred metric when the desired signal bandwidth is less than Nyquist bandwidth. First generation cellular base STATION is an example for this CONDITION. The AMPS signal is MUCH smaller in bandwidth when COMPARED to the spectrum allocation accessed by a cell site ADC.

Correct answer is (a) p=q^2/2R

The best EXPLANATION: p=q^2/2R is the relation between POWER and quantization step SIZE. R is the INPUT resistance.

Right option is (B) analog circuit and REVERSE engineering

The explanation is: RF MEMS allows the selection of switches from a collection of analog circuit and components. This is the direct implementation of MEMS in the design. REENGINEERING and selection of analog circuits are according to the programmability REQUIREMENTS of software DEFINED radio.

Correct OPTION is (a) Low insertion LOSS

The EXPLANATION is: A ROOFING filter must have low insertion loss, programmable bandwidth and programmable center frequency for effective interference suppression.

Right answer is (b) co-site interference

Easy explanation: The impact of physical location of the ANTENNAS on self-generated EMI is CALLED as co-site interference.It occurs when TWO or more closely located RF systems affect each other NEGATIVELY.

Correct answer is (a) True

Best explanation: Determining the AVERAGE performance, SELECTING a VARIANCE ratio, and using incomplete Gamma function are the STEPS involved in establishing specification.

Right option is (c) mutually consistent

Best explanation: Communication services are a PART of SOFTWARE radio architecture. They carry out APPLICATIONS such as internet access and radio-specific applications. Mutually consistent protocol profiles are DEFINED so that combinations of services and applications can WORK together.

Correct choice is (b) Inheritance

The explanation is: Property inheritance ALLOWS the definition of reusable classes of software OBJECTS. This allows the SYNTHESIS of task-specific objects. FIR is an example for a generic software OBJECT and mark filter is an example for task-specific software object.

Correct choice is (d) RF

Explanation: The development of a SDR involves accurate analysis of functional and statistical structure of hardware and SOFTWARE. The key STEP in SYSTEM analysis is the identification of processing resources and characterization of processing CAPACITY of DIGITAL hardware. Memory, DSP and workstation are few examples of digital hardware.

The CORRECT option is (d) personality

To EXPLAIN I would say: Each combination of band and MODE is a multiple personality. A personality combines RF band, CHANNEL set, air interface waveform, protocol, and related functions.

Correct answer is (d) SFDR

The explanation: Spurious Free Dynamic Range (SFDR) FIXES the input POWER dynamic range such that there are sinusoidal RF artifacts in the output. The artifacts TEND to mask weak SIGNAL.

The CORRECT option is (b) One-bit DIRECT conversion digital RECEIVER

For explanation I would say: One-bit direct conversion digital receiver AMPLIFIES RF until it is hard limited into a square wave. An advantage of this architecture is that the channel states are STORED in lookup tables.

Right choice is (a) True

For explanation I would say: DOPPLER spread introduces decorrelation as a function of antenna separation.The rule of THUMB for antenna diversity states that for an antenna separation of 10 wavelengths or more, there is a considerable probability for the diversity signal to be SUBSTANTIALLY decorrelated from the PRIMARY signal.

Right answer is (b) False

The explanation is: The degree of “reach” required is determined by the scope of the software components. If an object is LOCALLY DEFINED, then team LEVEL agreement on data and BEHAVIOR is sufficient. If it were to EXTEND among multiple teams, agreement on a large scale is required.

The correct answer is (c) use-case analysis

Explanation: A TRACE of the path created by stimulus-response event pair is CALLED thread. In UML TERMINOLOGY, the tracing of the interactions among external ACTORS and the encapsulated system is called use case analysis.

The correct choice is (b) False

The BEST I can explain: DSP consumes lot of power and is suitable for CHANNEL modem and baseband signal processing TASKS. ASIC is more power efficient and appropriate for front-end filtering.

Correct option is (c) bit-serial

Easy explanation: Forward error control OPERATIONS are bit-serial. It involves bit-level manipulations. They are USUALLY carried out in REGISTERS of length 11, 13 etc. Additional bit-masking is REQUIRED to implement FEC functions.

The correct ANSWER is (b) False

To elaborate: The increase in the third-order intermodulation product eventually results in the INTERSECTION of the fundamental signal with the power of third-order intermodulation product. This is referred as IP3. The output power of the fundamental signal SATURATES before IP3.The point at which the output noise power of the fundamental signal SHIFTS away from the ideal output power by 1-dB is called 1-dB compression point.

The CORRECT answer is (c) SINGLE RF/IF up-down conversion

To ELABORATE: Tunable pre-selector is required for co-site rejection. Low phase NOISE and fast tuning synthesizers are required for JTIDS and EPLRS. Single RF/IF up-down conversion is a commercial application CHALLENGE.

The CORRECT OPTION is (d) closed cooling SYSTEM, 70K

Explanation: Superconductor analog filters make use of closed cooling system, and thermo-electric COOLERS to MAINTAIN working temperature near 70K.

Right OPTION is (a) PROGRAMMABLE digital notch filters

To explain I would say: Physical antenna SEPARATION, frequency separation, programmable analog notch filters and active CANCELLATION are the steps used to control INTERFERENCE at RF.

The correct option is (b) False

Explanation: Lower gain ANTENNA reduces link margin and increases the outage PROBABILITY proportionally. These antennas become optimal when aggregate cost and quality of information services across the COMBINATION of bands and modes is considered.