ISRO Scientist or Engineer Electronics 2018
For the following questions answer them individually
For a feedback system shown below, If K: = 0 and K, = 5, then steady state error for unit ramp input is 0.2. What will be the new value of K: and Ka if damping ratio is increased to 0.5 without affecting steady state error:
For a negative unity feedback system, Gain is given by
$$G(s) = \frac{0.25}{((s^2 + 1)(8s + 3))}$$
Transfer function of a lead compensator aimed at achieving gain crossover frequency of 0.5 rad/sec and phase margin of 30 deg is
A sensitivity of transfer function $$T = \frac{(A_1 + kA_2)}{(A_3 + kA_4)}$$ with respect to parameter k is given by
If over the course of a day, the maximum electron density in the ionosphere varies from $$10^{11}$$ to $$10^{12}$$ $$m^{-3}$$; the critical frequency changes approximately from:
What is the peak to average power ratio for the signal $$x(t) = A \sin(\omega t)$$ with 50% duty cycle?
A binary communication system receives equally likely symbols $$x_1(t)$$ and $$x_2(t)$$ plus Additive White Gaussian Noise at the input of matched detector. If the noise power spectral density ($$N_o$$) is $$10^{-11}$$ W/Hz, compute $$E_b/N_o$$ (in dB). Assume system characteristics impedance as 1Ω.
x(t) = {
1, $$0 \leq t \leq T$$
0, Otherwise
}
h(t) = {
t, $$0 \leq t \leq 2T$$
0, otherwise
}
Calculate $$y(t) = x(t) * y(t)$$, where * denotes convolution for interval $$T \leq t \leq 2T$$
For the below mentioned 8051 assembly code
Timeelapse : MOV RO, #100
Part 1 : MOVRI, #50
Part 2 : MOV R2#248
Part 3 : DJNZ R2, Part 3
: DJNZ R1, Part 2
: DJNZ RO, Part 1
Assumptions:
* Microcontroller is running at 12 MHz frequency and 1 machine cycle is having 12 clock cycles
* MOV instruction takes 1 Machine cycle
* DJNZ instruction takes 2 Machine cycle
Calculate time required for execution of Part 1
A. Program Counter(PC) Pushedto Stack
B. Generate LCALLto ISR
C. Complete Execution of instruction in progress
D. Clear the interrupt flag
E. Set interrupt in progress
Correct order of execution of action taken by 8051 micro-controllers when an interrupt occurs:
