Fundamentals of Mixed Signals and Sensors

The most inefficient amplifier class of amplifier.

• Class AB Amplifier
• Class B Amplifier
• Class C Amplifier

Decimation involves the use of which of the following components?

• Digital anti-aliasing filter
• Sampling rate expander
• Sampling rate compressor

What is the z-transform of the signal x=[3(2n)-4(3n)]u?

• 3/(1+2z-1)-4/(1+3z-1)
• None of the above
• 3/(1-2z)-4/(1-3z)
• 3/(1-2z-1)-4/(1-3z-1)

Capacitance Transducers are used to measure acceleration along one or more axis and are relatively insensitive to orthogonal directions

• True
• False

the inverse z-transform can be performed by evaluating a Answer integral

• x+y =E2=86=94X(z)Y(z)
• xy =E2=86=94X(z)+Y(z)
• xy =E2=86=94X(z)Y(z)
• x+y =E2=86=94X(z)+Y(z)

The sampling frequency should be less than the highest frequency contained in the signal.

• True
• False

The FET's three terminals are Source,Drain and CollectorBaseGate

• Class A Amplifier
• Class B Amplifier
• Class C Amplifier

Is the discrete time LTI system with impulse response h=an (|a| < 1) BIBO stable?

• A two-sided sequence (neither left nor right-sided) has a ROC consisting of a ring in the z-plane, bounded on the interior and exterior by a pole
• The ROC cannot contain any poles
• ROC is a disconnection region
• The Fourier transform of x[n] converges absolutely if and only if the ROCof the z-transform includes the unit circle

What are the types of Transistor? (Choose two)

A device is a Answer when input is electrical and output a physical quantity

• True
• False

Decimation works by inserting zero-valued samples for each input signal.

• True
• False

A continuous signal can be represented as the product of an impulse function and the signal itself.

• A delay in the function by 3 units in time
• The function itself
• An advance in the function by 3 units in time
• Cannot be determined

The subscript ___________ is added to the period of clock signal T to emphasize that it's the clock signal.

• T
• CLK
• Ton

Data conversion accuracy enhances system performance In-depth understanding of data converter performance is important in many applications.

• True
• False

Electric Field transmission lines Magnetic Field coaxial lines sensors are used for power steering,security, and current measurements on Electric Field transmission lines Magnetic Field coaxial lines

• True
• False

Identify which is NOT a step for converting a block diagram into an equivalent signal flow graph.

• Represent the transfer functions inside the blocks of diagrams as gains of the signal flow diagram
• Represent the blocks of diagram as branches in signal flow graph
• Represent all the signals, variables, and summing points and take-off points as branches

Class AB that has lower efficinecy of less thant 40% but good signal reproduction and linearity.

• True
• False

What is the ROC of z-transform of finite duration anti-causal sequence?

• z=E2=88=9E
• Entire z-plane, except at z=0
• z=0

It refers to the measure of similarity between two signals

• True
• False

Which of the following series has an ROC as mentioned below?

• αnu
• α-nu
• α-nu(-n)

What is the formula for noise power spectral density?

• Total power / bandwidth
• Bandwidth / Total power
• Noise power of signal/Interpolated signal

It is a measure of the step size error

• sampling jitter
• Monotonicity and missing codes
• Effective number of bits

Which is NOT an effect of aliasing?

• Wagon wheel effect
• Retinal images
• Text images

What is the set of all values of z for which X(z) attains a finite value?

• 3/(1-2z)-4/(1-3z)
• None of the above
• 3/(1-2z-1)-4/(1-3z-1)
• 3/(1+2z-1)-4/(1+3z-1)

Large signals uses this kind of amplifier

• True
• False

A signal flow graph is the graphical representation of the relationships between the variables of set linear algebraic equations.

• True
• False

Which is NOT a property of the region of convergence?

• ROC is a disconnection region
• A two-sided sequence (neither left nor right-sided) has a ROC consisting of a ring in the z-plane, bounded on the interior and exterior by a pole
• The Fourier transform of x[n] converges absolutely if and only if the ROC of the z-transform includes the unit circle
• The ROC cannot contain any poles

DeconvolutionCorrelation is the reverse process of convolution widely used in signal and image processing

• t=0
• t>0
• Always
• t<0

It is a mathematical operation used to express the relation between input and output of an LTI system

• True
• False

For a causal L.T.I. system, the impulse response is 0 for _________

• Auto Correlation
• Discrete Correlation
• Cross Correlation

Which of the following variations can be done to make capacitance based sensors ? (Choose one or more)

What should be the sampling frequency if the highest frequency of the signal is 5Hz?

• 25Hz
• 10Hz
• 5hz

Class C amplifier is used for VHF, UHF and SHF Frequencies.

• True
• False

Increasing the input code should always increase the output voltage.

• True
• False

Identify the FET terminals stated :blankSource , terminal through which the carriers enter the channel blank Drain , where the carriers leave the channel blankGate , the terminal that modulates the channel conductivity

• Field-emitter Transistor
• Filter-effect Transistor
• Field-effect Transistor

Signal flow graphs are reliable to find transfer function than block diagram reduction technique.

• True
• False

What is ADC?

• Analog-to-Digital Converter
• African Democratic Congress
• Attack Damage Carry

Switched capacitor-integrator is more accurate than continuous time integrator.

• True
• False

Which is NOT a property of convolution?

• Shifting property
• Differentiation of Output
• Convolution with impulse
• Integration of Output

Class A amplifier is more efficient than Class B amplifier.

• True
• False

Power Density Spectrum is the measure of similarity between two different signals.

• Power Density Spectrum
• Energy Density Spectrum

At what frequency should a signal composed of a single sinewave at a frequency of 6 Hz be sampled in accordance to the Nyquist Theorem?

• 6Hz
• 3Hz
• 12Hz

Aliasing arises when a signal is discretely sampled at a rate that is insufficient to capture the changes in the signal.

• True
• False

Power amplifier delivers power to the load and is the product of the voltage and current applied to the load with the output signal power being greater that the input signal power.

• True
• False

A branch has gain but no direction.

• Represent all the signals, variables, and summing points and take-off points as branches
• Represent the transfer functions inside the blocks of diagrams as gains of the signal flow diagram
• Represent the blocks of diagram as branches in signal flow graph

Which of the following is/are NOT a detectable phenomena?

Ultrasonic sensors are used for position measurements.

• True
• False

Switched capacitor circuits can be used to build regulators.

• True
• False

What density spectrum can be measured in this formula?

• None of the above
• Doubling the signal
• Squaring the signal
• Adding two signals

The cost is an economic factor to consider in choosing a sensor.

• Transducer
• Resistor
• Sensor

Which of the following justifies the linearity property of z-transform?[x↔X(z)].

• x+y ↔X(z)Y(z)
• xy ↔X(z)+Y(z)
• xy ↔X(z)Y(z)
• x+y ↔X(z)+Y(z)

Biological Phenomena is a common detectable phenomena.

• True
• False

_Answer is used to measure deflection, stress, pressure, etcThe resistance of the sensing element changes with applied strain

• True
• False

What is DAC?

• Deferred Acquisition Costs
• Digital-to-Analog Converter
• Development Assistance Committee

The three terminals of a semiconductor are called emmiter,base and gate.

• True
• False

What is the classification of amplifier that uses the common emitter configuration of transistor?

• Class B Amplifier
• Class A Amplifier
• Class C Amplifier

The convolution of a function with an impulse function delayed to an instant 3 in time results in ____________

• A delay in the function by 3 units in time
• Cannot be determined
• An advance in the function by 3 units in time
• The function itself

Auto correlation function and energy spectral densities are Fourier transform pairs.

• True
• False

What is the z-transform of the signal x= -=CE=B1nu(-n-1)?

• True
• False

Tells us the frequency where the SINAD is 3 dBlower than the best case value

• True
• False

The range of a convuluted signal of two unequal rectangles is the difference of the lower limits and upper limits.

• Shifting property
• Differentiation of Output
• Convolution with impulse
• Integration of Output

Which of the following is/are an analog input/output ?

• video
• motion
• switch
• audio

Multirate systems can increase or decrease the sampling-rate of a signal.

• True
• False

In an amplifier, if a capacitor can be accurately controlled, then the gain cannot be accurately controlled.

• True
• False

FET stands for _____________.

What is the z-transform of the signal x B1nu(-n-1)?

• True

Data converters must represent blank continuous values in a range using a set of discrete values A blank binary code is used to represent the value

• True
• False

Small Amplifiers are designed to amplify very small signal voltage levels of only a few Class A AmplifiersSmall Signal AmplifiersLarge Signal Amplifiers from sensors or audio signals

• True
• False

The ADC quantizes the input voltage to a finite number of bits.

• Figure of merit
• Figure of error

The narrowband amplifies a specific range of frequencies, to the exclusion of other frequencies.

• True
• False

The FET is a unipolar junction transistor.

• common base
• common collector
• common emitter
• common gate

A Answer is a line segment which joins two nodes

• zkX(z)
• z-kX(z)
• X(z-k)
• X(z+k)

The opposition exhibited by its output terminals to an alternating current (AC) of a particular frequency is called Amplifier Efficiency.

• True
• False

According to Time shifting property of z-transform, if X(z) is the z-transform of x then what is the z-transform of x(n-k)?

• X(z+k)
• zkX(z)
• z-kX(z)
• X(z-k)

The resulting signal when a continuous time periodic signal x(t) having period T, is convolved with itself is a periodic having period of T/2

• True
• False

A measure of the "amplification" of an amplifier

• Gain
• Impedance
• Efficiency

The common conversion methods are Physical, RadioactiveChemicalMagnetic , and biological

The convolution of a discrete signal with itself is _________

• Squaring the signal
• None of the above
• Doubling the signal
• Adding two signals

Which is not a type of correlation?

• Auto Correlation
• Cross Correlation
• Discrete Correlation

Faraday’s Law of Induction states that coil resist a change in magnetic field by generating an opposing voltage/current

• True
• False

Happens in ADCs when an output code does not occur for any input voltage

• video
• switch
• audio
• motion

The simple way to avoid aliasing of course is to always have enough samples to capture the spatial or temporal variations in a signal.

• True
• False

Flywheel Effect See back Effect to transform a temperature difference to a voltage difference

• True
• False

Increasing the input code should always decrease the output voltage.

• True
• False

The easiest way to smooth a signal is to increase its resolution.

• True
• False

Transistor where the current condition is due to both charge carries of holes and electrons

• True
• False

Radio Frequencies uses Class B amplifier with the configuration of common collector .

• True
• False

Use mason’s gain formula to find the transfer function of the given signal flow graph:

• adcdef/1-(bc+ef)+bcef
• abd/1-(bc+ef)+bcef
• abd/1-(ac)
• abdeg/1-(bc+ef)+bcef

a numerical expression representing the performance or efficiency of a procedure.

• Figure of merit
• Figure of error

The two types of convolution are continuous and discrete convolution.

• True
• False

This tells us how many of these bits contains useful information.

• Uniform quantization steps are not constant
• Quantization error uncorrelated with input
• All quantization levels have equal probability

Which is NOT a transistor configuration?

• common emitter
• common gate
• common base
• common collector

Which is NOT a quantization noise assumption?

• Uniform quantization steps are not constant
• All quantization levels have equal probability
• Quantization error uncorrelated with input

The multistage approach allows a significant relaxation of the anti-alias and anti-imaging filters, with a consequent reduction in the filter complexity

• True
• False

Which is NOT a static specification?

• Monotomy
• Missing codes
• Offset
• jitter

The term SONAR stands for "Solar Navigation and Radar"

A device which converts one form of energy to another

• Sensor
• Transducer
• Resistor

Refers to the preservation of information.

• Interpolation
• Decimation