# Recent questions and answers in Digital Signal Processing

1
At a room temperature of $300K$, calculate the thermal noise generated by two resistors of $10K\Omega$ and $20K\Omega$ when the bandwidth is $10KHz$. $1.2868\times10^{-6}V, 1.819\times10^{-6}V$ $6.08\times10^{-6}V, 15.77\times10^{-6}V$ $16.66\times10^{-6}V, 2.356\times10^{-6}V$ $1.66\times10^{-6}V, 0.23\times10^{-6}V$
2
Microprocessors are used in which generation of computers? I – st Generation II – nd Generation III – rd Generation IV – th Generation
3
An ideal op-amp is an ideal voltage controlled current source voltage controlled voltage source current controlled current source current controlled voltage source
4
Twelve $1\;\Omega$ resistances are used as edges to from a cube. The resistance between two diagonally opposite corners of the cube is $\frac{5}{6}\;\Omega$ $\frac{1}{6}\;\Omega$ $\frac{6}{5}\;\Omega$ $\frac{3}{2}\;\Omega$
5
In MOSFET fabrication, the channel; length is defined during the process of Isolation oxide growth Channel stop implantation Poly-silicon gate patterning Lithography step leading to the contact pad
6
Twelve $1\;\Omega$ resistances are used as edges to from a cube. The resistance between two diagonally opposite corners of the cube is $\frac{5}{6}\;\Omega$ $\frac{1}{6}\;\Omega$ $\frac{6}{5}\;\Omega$ $\frac{3}{2}\;\Omega$
7
The final value theorem is used to find the Steady state value of the system output Initial value of the system output Transient behavior of the system output None of these
8
For the discrete signal $x[n] = a^{n}u[n],a>0$ the $z$-transform is $\frac{(z+a)}{z}$ $\frac{(z-a)}{z}$ $\frac{z}{(z-a)}$ $\frac{z}{(z+a)}$
9
For a periodic signal $v(t) = 30\sin 100t + 10\cos 300t + 6\sin(500t + \frac{\pi}{4}),$ the fundamental frequency in rad/s $100$ $300$ $500$ None of these
10
If the number of bits per sample in a PCM system is increased from a $n$ to $n+1,$ the improvement in signal to quantization nose ratio will be $3\;dB$ $6\;dB$ $2n\;dB$ $n\;dB$
11
A carrier $Ac\cos(\omega c)t$ is frequency modulated by a signal $Em\cos(\omega m)t.$ The modulation index is $mf.$ The expression for the resulting FM signal is $Ac\cos [\omega ct + mf\sin(\omega m)t]$ $Ac\cos [\omega ct + mf\cos(\omega m)t]$ $Ac\cos [\omega ct + \pi mf\sin \omega m t]$ $Ac\cos [\omega ct + 2\pi mf Em \cos(\omega m)t/\omega m]$
12
In MOSFET fabrication, the channel; length is defined during the process of Isolation oxide growth Channel stop implantation Poly-silicon gate patterning Lithography step leading to the contact pad
13
The open-loop transfer function of a feedback control system is $G(s)\cdot H(s) = 1/(s+1)^{3}.$ The gain margin of the system is $2$ $4$ $8$ $16$
14
The sequence of operation in which PCM is done is Sampling, quantizing, encoding Quantizing, sampling, encoding Quantizing, encoding, sampling None of the above
15
The IETF standard documents are called: RFC RCF ID none of the above
16
$T1$ carrier system is used: For delta modulation Industrial noise For frequency modulated signals None of the above
17
In a microprocessor, WAIT states are used to make the processor wait during a DMA operation make the processor wait during a power interrupt processing make the processor wait during a power shutdown interface slow peripherals to the processor
18
A low pass filter is Passes the frequencies lower than the specified cut off frequency Used to recover signal from sampled signal Rejects higher frequencies All of the above
19
Microprogramming is a technique for writing small programs effectively programming output/input routines programming the microprocessors programming the control steps of a computer
20
A stable multivibrator are used as comparator circuit squaring circuit frequency to voltage converter voltage to frequency converter
21
The astable multivibrator has two quasi stable states two stable states one stable and one quasi-stable state none of these
22
At $100\%$ modulation, the power in each sideband is _______ of that of carrier. $50\%$ $40\%$ $60\%$ $25\%$
23
The communication network comprises number of base stations. The scope of each base station covers the circular area. To avoid the overlapping and gaping of areas, the scope of each base station is accounted by Rectangle Pentagon Hexagon Octagon
24
In a communicative network, though the scope of base station is circular area, the network scope is represented by______ shape, as it is nearest to the circular area. triangular rectangular pentagonal hexagonal.
25
Consider a discrete memoryless channel and assume that H(x) is the amount of information per symbol at the input of the channel; H(y) is the amount of information per symbol at the output of the channel. H(x $\mid$ y) is the amount of uncertainty remaining on x knowing y; and I(x;y)is the information transmission. ... -H(y $\mid$ x)]; p(x) max [H(x)-H(x $\mid$ y)]; p(x) max H(x $\mid$y); p(x)
26
A Butterworth lowpass filter of order $n$, with a cutoff frequency at distance $D_{0}$ from the origin, has the transfer function $H(u, v)$ given by $\frac{1}{1+\left[\frac{D(u, v)}{D_{0}}\right]^{2n}}$ $\frac{1}{1+\left[\frac{D(u, v)}{D_{0}}\right]^{n}}$ $\frac{1}{1+\left[\frac{D_{0}}{D(u, v)}\right]^{2n}}$ $\frac{1}{1+\left[\frac{D_{0}}{D(u, v)}\right]^{n}}$
27
Given two spatial masks $S_{1}= \begin{bmatrix} 0&1&0 \\ 1&-4&0 \\ 0&1&0 \end{bmatrix}$ $S_{2} = \begin{bmatrix} 1&1&1 \\ 1&-8&1 \\ 1&1&1 \end{bmatrix}$ The Laplacian of an image at all points $(x, y)$ can be implemented by convolving the image with spatial mask. Which of the following can be used as the spatial mask ? only $S_{1}$ only $S_{2}$ Both $S_{1}$ and $S_{2}$ None of these
28
3sin(200rt) is amplitude modulated with 600s(6000rt) Find the spectral response and expression of the AM signal generated
1 vote