An LTI system has the input signal x(n). Which of the following sequence of operations is most appropriate to get output $$y(n) = x \left(n - \frac{M}{L}\right)$$.
ISRO Scientist or Engineer Electronics 2010
For the following questions answer them individually
Consider a low pass random process with a white noise power spectral density
$$ S_{x} (\omega)=\frac{N}{2}$$ where $$-2 \pi B \leq \omega \leq 2 \pi B $$
0 elsewhere
The Auto-correlation function $$R_{x}(\tau)$$ is
Pole-zero plot of a digital filter is shown below, what is the type of filter?
Determine the DTFT of the sequence $$y[n] = (n + 1) \alpha^{n} u[n], \mid \alpha \mid < 1.u[n]$$ is unit step sequence
The function f(t) has the Fourier transform g$$(\omega)$$. The Fourier transform of g(t) is
The purpose of Design for Test (DFT) process in ASIC design flow is
The coupling between the two inductors is increased from zero in the circuit shown.' Which of the following statements is true?
Write a Boolean expression for Z in terms of A, B, C, D and E. You need not simplify the expression.
Aparallel plate capacitor of 100 pf having an air dielectric is charged to 10 kilovolts. It is then electrically isolated. The plates are pulled away from each other until the distance is ten times more than before. Estimate the energy neededto pull the plates.-
How could Schroedinger’s equation be relevant in the practical design of a CathodeRay Tube?
When compared with stripline, the major disadvantage of microstrip line is
The disadvantage of single-stub matching as compared to double-stub matching,is that
A charge $$Q_{2} = 8.854 \times 10^{-9}$$ C is located in a vaccum at $$P_{2}(2, 3, 1)$$.The force on $$Q_{2}$$ due to a charge $$Q_{1} = 4 \pi \times 10^{-3}$$ C at $$P_{1}(2, 2, 1)$$ is
If a material contains $$10^{20}$$ molecules/m$$^3$$, each molecule having a moment of $$8.854 \times 10^{-27}$$ C-m parallel to an electric field of $$10^{5}$$ V/m, then its dielectric constantis
If every minor of order ‘r’ of a matrix ‘A’ is zero, then rank of ‘A’is
Which of the following is true
What is the maximum clock frequency at which following circuit can be operated | without timing violations? Assume that the Combinational logic delay is 10 ns and the clock duty cycle varies from 40% to 60 %.
Following shift register is initially loaded with the bit pattern “1010”. After how many clock cycles will the content of shift register be “1010” again?
Which oneofthe followingis the lowest level of abstraction for representation of a digital system?
The content of the accumulator of 8085 microprocessor after execution of the following instructions will be
MVI A, A7h
ORA A
RLC
For CMOSimplementation of 2 input XORlogic gate, how many nMOSand pMOS transistors are required?
Whichofthe following principles is applied while designing the output matching networkfor a high power Class-C amplifier?
Find the approximate output impedance of the VCCS(voltage-controlled current . source) based circuit at port Vo.
Which of the following parameters of a Silicon Schottky Diode is higher than that of a corresponding PN junction diode?
Assume the intrinsic standoff ratio for the UST is 0.8 for the relaxation oscillator circuit given below. The frequency of oscillation of this circuit is approximately equal
The approximate frequency of oscillation of the circuit shown below is
A unit step voltage travels from left to right along an infinite transmissionline. It hits an inductive discontinuity at t=0. What will be the waveform immediately to the left of the discontinuity?
A lossy open stub having a length of $$\frac{1}{32}$$ wavelength, is approximately equivalent to
Ampere's law relates
Across which type of boundary doesthe electric field have a continuous tangential component?
Laplace Transform of $$e^{at}t^{n}$$ is
For $$- \infty < x < \infty \& -1 < y < 1$$, the partial differential equation $$ x^{2} \frac{\partial^{2} u}{\partial x^{2}} + (1 - y^{2}) \frac{\partial^{2} u}{\partial y^{2}} = 0$$ is
A CMOSdigital circuit consumes P watts of dynamic power while operating at 20 MHz clock frequency and 5V supply. Whatwill be its dynamic power consumption if the clock frequency is increased to 40 MHz and supply voltage is decreased to 2.5V?
A communication channel with Additive White Gaussian Noise, has a bandwidth of 4 kHz and SNRof31dB. Its channel capacity is
If the total power of an-amplitude modulated signalis 600W and the carrier power is 400W,the modulation indexis
What is the advantage of Offset QPSK (OQPSK) compared to conventional QPSK?
An angle modulated signal with carrier frequency $$\omega_{c} = 2 \pi \times 10^{5}$$ is described by the equation $$s(t) = 10 \cos (\omega_{c} t + 5 \sin(3000 \pi t) + 10 \sin (2000 \pi t))$$. What is the frequency deviation $$\triangle$$ f ?
The Fourier transform of a signal $$x(t) = e^{-4\mid t \mid}$$
What is the output waveform $$V_{o}$$ for a sinusoidal input of peak-peak amplitude of 4V. Assume that Z1 and Z2 are two identical Zener diodes of 4.7V, and R1 = 10kohm and R2 = 20kohm.
For a particular toroidal inductor core, the inductance value obtained for 50 Turns is $$200 \mu H$$. If two such inductors are wired in parallel, the resulting inductanceis
The magnetic equivalent of Ohm’s Law is
It is required to design a class B output stage (as shown below) to deliver an average output power of 12.5W to a load of 4Ω. The power supply is selected so that $$V_{cc}$$ is 5V greater than the peak output voltage. Determine the power conversion efficiency, of the circuit.
Which type of circuit has an input impedance as shown in this polar plot?
A coaxial transmission line carrying an RF signalis perfectly matched to the load. Consider the cross-section of the line, at a plane where the instantaneousvoltageis at its maximum value. How will the curl of the E-field vary over this cross-section?
The continuity of the tangential field componentat the interface of two media for normal incidence of a plane wave requires
Which modeof a circular waveguide will have the lowest attenuation?
If $$\psi = 2x^{2}y - xz^{3}$$, then the Laplacian of $$\psi$$ is
What does the following integral evaluate to?
$$\int_{0}^{\frac{\pi}{2}} \sin^{6} \theta .d \theta$$
A signal with two frequency components at 6 kHz and 12 kHz, is sampled at the rate of 16 kHz and then passed through a Low Passfilter having a cut-off frequency of 16 kHz. The output signalof the filter
What is the greatest allowable PRF for unambiguous reception in a radar having a maximum range of 120 km?
A microprocessor has a cache memory with access time of 2 ns and a main memory with access time of 10 ns. If the cache missratio is 0.6, what is the average memory access time?
Consider the following assembly code for a hypothetical RISC processor with a 4-stage pipeline (Instruction Fetch, Decode/Register Read, Execute and Write).
add $$r_{1},r_{2},r_{3} \parallel r_{1} = r_{2} + r_{3}$$
sub $$r_{4},r_{1},r_{3} \parallel r_{4} = r_{1} - r_{3}$$
mul $$r_{5},r_{2},r_{3} \parallel r_{5} = r_{2} \star r_{3}$$
Identify the possible pipeline hazard and the affected instruction.
A zero memory source emits six messages with probabilities 0.3, 0.25, 0.15, 0.12, 0.1 and 0.08. If binary Huffmancodingis used, what will be the average code length?
In the circuit given below, assume that $$V_{cc}= 15V; Z_{1}, Z_{2}, Z_{3} \& Z_{4}$$ are identical zener diodes with breakdownvoltage of 5V; $$R_{1} = R_4 = 5kΩ, R_{2} = R_{3} = 10kΩ$$. Find $$V_{o}$$ when $$Q_{1}$$ is OFF.
Assume that $$V_{i}= 2V; R_{3} = 10Ω; \beta$$ of $$Q_{1} = 50; V_{cc} = 15V$$. Find $$I_{out}$$.
A sample and hold amplifier is connected to an ADC. The acquisition time of the sample and hold amplifier is 10 usec and the conversion time of the ADCis 15 psec. What is the highest possible data rate?
In an inverting OP-AMP,the input bias currentis -1$$\mu$$A, and the input and the feedback resistances are both 1MQ. What will be the output voltage for an input voltage of 2.5V?
Which of the following devices can be used for generating a PWM signal?
A microwavereceiving antenna on a satellite is pointing towards the earth. The antenna beamwidth is 50 degrees. The earth subtends 5 degreesat the satellite. What will be the noise temperature of the antenna?
Estimate the magnitude and phase of the element $$S_{11}$$ of the S-matrix of the circuit shown below. Assume an operating frequency of 25 MHz.
The electric field measured in the far field of an antenna at a distance of 50m is 1 $$\frac{V}{m}$$. The average powerdensity at a distance of 500m from the antenna is
A quarter wave monopole antennais situated above a perfectly conducting ground plane.It is driven by a 50V source at 500MHz through an internal impedance of 63.5Ω . The average powerradiated by the antennais
Directional derivative of $$U = 2x^{3}y - 3y^{2}z$$ at P(1, 2, -1) in a direction towards Q(3, -1, 5) is
Consider the equation Re(1/z)=c, where z is a complex number,c is a nonzero constant and Re( ) represents the real part. The equation describes a
How many adders are required to realize a 256 point radix-2 FFT using decimation-in-time?
A uniformly distributed randomsignal x[n] with mean $$m_{x} = 2$$ and variance $$\sigma_{x}^{2} = 3$$, is passed through a 3-point moving-averagefilter having an impulse response $$\left\{h[n]\right\}=\left\{\frac{1}{3},\frac{1}{3},\frac{1}{3}\right\}$$ What will be the mean andvariance of output?
A sine waveis applied to a balanced modulator. The peak output envelope poweris 1000 times the minimum output envelope power. Estimate the carrier suppression in
dBc.
Consider a single error correcting (7, 4) cyclic code with generator matrix $$g(x) = x^3 + x^{2} + 1$$. Whatwill be the transmitted data if received vector r is 1101101?
Consider a Golay’s (23,12) codewith t bits of error correction capability. For what value of t will the codeexactly satisfy the Hamming bound ?
The maximum range of a monostatic Radar is R. If a target having a Radar cross section of $$10m^{2}$$ exists at $$\frac{R}{2}$$ what should be the target cross-section at $$\frac{3R}{2}$$ to result in an equalsignal strength at the Radar?
Theelectric field intensity at a distance of 10km from an antenna having a directive gain of 10dB andradiating a total power of 60kW is
What is the characteristic impedance of a coaxial transmission line having inner conductor radius of Imm, outer conductor radius of 2mm anddielectric constant of 4.0?
Animpedance of -10 — j2 ohmsis connected to another impedance of 45 + j5 ohms through a transmission line having a characteristic impedance of 50 ohms. Assess the stability of this circuit
A transmission line of characteristic impedance 75 ohms is terminated with an impedance of 50 ohms. The line length is increased from zero. What will be the locus of the input impedance at the other end of the line? (N.B. : Reference impedance of Smith Chart = 50 Ohms)
The value of the integral $$\int \frac{\sin Z}{Z^{3}} .dz$$ around the circle $$\mid Z \mid = 2$$ is
Which of the following functions have a jump discontinuity at x = 0
What would be the output of the following circuit, if a positive going unipolar pulse with an amplitude greater than $$V_ref$$, is applied at the input?
What is the output voltage across the 900 ohm load in the circuit given below?.
What is the transfer function of the network given below?
A voltage regulator having $$V_{ref}$$=1.25V needs to generate 5V output. Assumethat $$I_{adj}$$ = 100nA and $$R_{1}$$ = 10kohm. What should be value of $$R_{2}$$?
