GATE 2004 Electronics & Communication
48 questions across 1 session
An ideal Op-Amp is an ideal
The minimum number of 2 to 1 multiplexers required to realize a 4 to 1 mutliplexer is
Consider the following statements S1 and S2. S 1 : The $$\beta$$ of a bipolar transistor reduces if the base width is increased. S 2 : The $$\beta$$ of a bipolar transistor increas...
A causal system having the transfer function $$G\left(s\right)\;=\;\frac1{s\;+\;2}$$ is excited with 10u(t). The time at which the output reaches 99% of its steady state value is
For the polynomial P(s) = s 5 + s 4 + 2s 3 + 2s 2 + 3s + 15 , the number of roots which lie in the right half of the s-plane is
The range of signed decimal numbers that can be represented by 6-bite 1’s complement number is
11001, 1001 and 111001 correspond to the 2’s complement representation of which one of the following sets of number?
A system described by the following differential equation $$$\frac{d^2y}{dt^2}+3\frac{dy}{dt}+2y=x\left(t\right)$$$ is initially at rest. For input x(t) = 2u(t), the output y(t) is
The state variable equations of a system are: $$${\mathop {{x_1} = - 3{x_1} - x}\limits^ \bullet _2} + u$$$ $$${\mathop x\limits^ \bullet _2} = 2{x_1}$$$ $$$y = {x_1} + u.$$$ The s...
A system has poles at 0.01 Hz, 1Hz and 80 Hz; zeroes at 5hz, 100 Hz and 200 Hz. The approximate phase of the system response at 20 Hz is
A system has poles at 0.01 Hz, 1 Hz and 80 Hz; zeros at 5 Hz, 100 Hz and 200 Hz. The approximate phase of the system response at 20 Hz is
Choose the correct one from among the alternatives A, B, C, D after matching an item from Group 1 with the most appropriate item in Group 2. Group1 P. shift register Q. Counter R....
The 8255 Programmable Peripheral Interface is used as described below. I. An A/D converter is interfaced to a microprocessor through an 8255. the conversion is initiated by a signa...
Consider a binary digital communication system with equally likely $$0’s$$ and $$1’s$$. When binary $$0$$ is transmitted the voltage at the detector input can lie between the level...
An AM signal and a narrow-band FM signal with identical carriers, modulating signals and modulation indices of 0.1 are added together. The resultant signal can be closely approxima...
Three analog signals, having bandwidths 1200 Hz, 600 Hz and 600 Hz are sampled at their respective Nyquist rates, enocodes with 12 bit words, and time division multiplexed. The bit...
In the output of a DM speech encoder, the consecutive pulses are of opposite polarity during time interval t 1 $$ \le $$ t $$ \le $$ t 2 . This indicates that during this interval
The phase velocity of an electromagnetic wave propagating in a hollow metallic rectangular waveguide in the $$T{E_{10}}$$ mode is
A 1 mW video signal having a bandwidth of 100 MHz is transmitted to a receiver through a cable that has 40 dB loss. If the effective one-sided noise spectral density at the receive...
The number of memory cycles required to execute the following 8085 instructions (I.) LDA 3000H (II.) LXI D, FOF 1H Would be
A plane electromagnetic wave propagating in free space in incident normally on a large slab of loss-less, non-magnetic, dielectric material with $$\varepsilon > {\varepsilon _0}$$....
Consider the sequence of 8085 instructions given below. LXI H, 9258 MOV A, M CMA MOV M, A Which one of the following is performed by this sequence?
It is desired to multiply the numbers 0AH by 0BH and store the result in the accumulator. The numbers are available in registers B and C respectively. A part of the 8085 program fo...
Choose the correct one from among the alternatives A, B, C, D after matching an item from Group 1 with the most appropriate item in Group 2. Group 1. FM 2. DM 3. PSK 4. PCM Group 2...
Consider a lossless antenna with a directive gain of + 6 dB. If 1 m W of power is fed to it the total power radiated by the antenna will be
A master slave flip-flop has the characteristic that
In a PCM system, if the code word length is increased from 6 to 8 bits, the signal to quantization noise ratio improves by the factor
The Boolean expression AC + B$$\overline C $$ is equivalent to
Given A $$ = \left[ {\matrix{ 1 & 0 \cr 0 & 1 \cr } } \right],$$ the state transition matrix e At is given by
If A = $$\left[ {\matrix{ { - 2} & 2 \cr 1 & { - 3} \cr } } \right],$$ then sin At is
Voltage series feedback (also called series-shunt feedback) results in
The transfer function $$H\left( s \right) = {{{V_0}\left( s \right)} \over {{V_i}\left( s \right)}}$$ of an R-L-C circuit is given by $$H\left( s \right) = {{{{10}^6}} \over {{s^2}...
A bipolar transistor is operating in the active region with a collector current of 1mA. Assuming that the 'β' of the transistor is 100 and the transconductance (g m ) and the input...
A Boolean function 'f' of two variables x and y is defined as follows: f(0,0)=f(0,1)=f(1,1)=1;f(1,0)=0 Assuming complements of x and y are not available, a minimum cost solution fo...
The z transform of a system is H(z) = $${z \over {z - 0.2}}$$ . If the ROC is $$\left| {z\,} \right|$$ < 0.2, then the impulse response of the system is
The impurity commonly used for realizing the base region of a silicon n-p-n transistor is
Consider the following statements S1 and S2. S1: The threshold voltage (V T ) of a MOS capacitor decreases with increase in gate oxide thickness S2: The threshold voltage (V T ) of...
The drain of an n-channel MOSFET is shorted to the gate so that V GS = V DS . The threshold voltage (V T ) of MOSFET is 1 V. If the drain current (I D ) is 1 mA for V GS = 2 V, the...
A causal LTI system is described by the difference equation $$2y\left[ n \right] = ay\left[ {n - 2} \right] - 2x\left[ n \right] + \beta x\left[ {n - 1} \right].$$ The system is st...
Consider the sequence $$x[n] = [ - \,4 - \,j5,\,\mathop {1 + j2}\limits_ \uparrow ,\,\,4]$$ The conjugate anti-symmetric part of the sequence is
A system described by the differential equation: $${{{d^2}y} \over {d{t^2}}} + 3{{dy} \over {dt}} + 2y = x(t)$$ is initially at rest. For input x(t) = 2u(t), the output y(t) is
The impulse response $$h\left[ n \right]$$ of a linear time-invariant system is given by $$h\left[ n \right]$$ $$ = u\left[ {n + 3} \right] + u\left[ {n - 2} \right] - 2\,u\left[ {...
The impulse response $$h\left[ n \right]$$ of a linear time invariant system is given as $$h\left[ n \right] = \left\{ {\matrix{ { - 2\sqrt 2 ,} & {n = 1, - 1} \cr {4\sqrt 2 ,} & {...
A 1 kHz sinusoidal signal is ideally sampled at 1500 samples /sec and the sampled signal is passed through an ideal low-pass filter with cut-off frequency 800 Hz. The output signal...
The Fourier transform of a conjugate symmetric function is always
A causal system having the transfer function H(s) = $${1 \over {s + 2}}$$, is excited with 10 u(t). The time at which the output reaches 99% of its steady state value is
An AM signal is detected using an envelope detector. The carrier frequency and modulating signal frequency are 1 MHz and 2 KHz respectively. An appropriate value for the time const...
Two sinusoidal signals of same amplitude and frequencies 10 kHz and 10.1 kHz are added together. The combined signal is given to an ideal frequency detector. The output of the dete...