List of top Electronics and Communication Engineering Questions

If a transmission line of characteristic impedance \( 25\,\Omega \) is to be matched to a load of \( 100\,\Omega \), then the characteristic impedance of the \(\lambda/4\) transmission line to be used is:
If maximum and minimum voltage on a transmission line are 2V and 5V respectively, VSWR is:
In a non-magnetic medium electric field \( E = E_0\cos\omega t \) is applied. If the permittivity of the medium is \( \varepsilon \) and the conductivity is \( \sigma \) then the ratio of the amplitudes of the conduction current density and displacement current density will be:
For electrostatic fields in charge free atmosphere, which one of the following is correct?
In a DPSK system the input bit sequence is 1101, initial phase = 0. The transmitted phase sequence is:
A binary signal is transmitted at 10kbps using NRZ signaling. Find the minimum channel bandwidth required in KHz:
A binary channel with bit rate of 56kbps is available for uniform PCM voice transmission having signal bandwidth of 3.4kHz. The signal-to-noise ratio in decibels is:
The carrier \( c(t) = A\cos(2\pi \times 10^6 t) \) is angle modulated (PM or FM) by the signal \( m(t) = 2\cos(4000\pi t) \). The deviation constants are \( k_p = 3\,\text{rad/V} \) & \( k_f = 3000\,\text{Hz/V} \). The value of modulation indices \( \beta_f \) & \( \beta_p \) are:
Overall gain of the system shown in the figure is:
Consider the unity feedback system with \( G(s) = \frac{2{S(S+1)(2S+1)} \). what is the phase margin?
What is the transfer function for given bode plot shown in the figure? \[ \text{} \]
A unity feedback second order system has \( G(s) = \frac{100{S^2+10S+100} \). The 2% settling time is in second.
The value of K for which the unity feedback system \( G(s) = \frac{K{S(S+2)(S+4)} \) crosses the imaginary axis is
The convolution of two DT sequence is,
\( x(n) = \{1 \uparrow, 2, 0, 1\} \)
\( h(n) = \{2, 2, 3\} \)
Consider a causal LTI system with frequency response \( H(j\omega) = \frac{1{j\omega + 3} \). This system produces the output to an input \( x(t) \) as \( y(t) = e^{-3t}u(t) - e^{-4t}u(t) \). The input \( x(t) \) is
The Fourier transform of a real valued time signal has _ _ _ _ .
A system is described by the differential equation \( \frac{d^2y(t){dt^2} + 6\frac{dy(t)}{dt} + 5y(t) = x(t) \). Impulse response of the system is
Consider the circuit, the next state \( Q^+ \) is \[ \text{} \]
The contents of accumulator after the execution of following instruction will be
MVI A, B7H
ORA A
RAL
The initial contents of the 4-bit serial-in-parallel out right-shift register shown in figure is 0110. After three clock pulse applied, the contents of the shift register will be \[ \text{} \]
The MUX shown in fig is \( 4 \times 1 \) multiplexer. The output Z is \[ \text{} \]
To double the drain current of an N-channel enhancement mode MOSFET biased in saturation _ _ _ _ .
An amplifier without feedback has a voltage gain of 50, input resistance of 1 k\(\Omega\) and output resistance of 2.5 k\(\Omega\). The input resistance of the current-shunt negative feedback amplifier using the above amplifier with a feedback factor of 0.2, is
What does the parameter \( S_{11} \) represent in a two-port network?
Fresnel zone is also called as _________.