ISRO Scientist or Engineer Electronics 2020
For the following questions answer them individually
A data sequence x[n] = {1,2,3,4,5} passes through a linear time-invariant system with impulse response h[n] = {5, 4, 3, 2, 1}. The output of the filter will be
Consider a signal $$\mu (t)$$ with the fourier transform V(f).If v'(f) represents the Fourier transform of $$\mu(2t)$$, what is the relation of V'(f) and v(f)?
If one of the code words of a Hamming (7,4) code is 00010111,which of the folllowing can not be the valid code wordin the same group ?
A mobile antenna receives two copies of the signal transmitted by the base section .The first copy is the line of sight component and the other is a reflected component
which is 20 dB weaker in terms of power than the Los component and delayed by 100 ns .If the signal is sufficiently wide band , causing constructive and destructive interference at different frequency points with in the signal bandwidth .what will be the ratio of maximum to minimum signal level varaition across bandwidth and what will be the frequency separation between two consective maxima or minima?
An antenna with an efficiency of 90% has a maximum Radiation intensity of 0.5 W/Steradiam. Calculate the directive gain of the antenna when the input power to the antenna is 0.4 W
In a semiconductor device, if Fermi level $$(E_{F})$$ is positioned at conductive band $$(E_{c})$$. Determine the Approximate probability of finding electrons in states at $$(E_{c} + kT)$$
(where K is Boltzmann constant and T is device temperature in Kelvin)
For the following energy band diagram, determine the approximate resistivity for x > L portion of semiconductor.$$E_{g} = 1.12 eV, T=300 K, \mu_{n} = 600 cm^2/V-sec, \mu_{P} = 400 cm^2/V-sec, n_{i} = 10^{10}/cm^3$$
The radiation intensity of a given anteena is $$U = 2 (\sin \theta \sin \phi)$$ in the range $$0 \leq \theta \leq \pi$$ and $$0 \leq \phi \leq \pi$$ and 0 else where .The directivity is
