| 1 |
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 |
Group 2 |
1: FM
2: DM
3: PSK
4: PCM |
P: Slope overload
Q: m -law
R: Envelope detector
S: Capture effect
T: Hilbert transform
U: Matched filter |
|
| Options |
| A) 1-T, 2-P, 3-U, 4-S |
B) 1-S, 2-U, 3-P,
4-T |
| C) 1-S, 2-P, 3-U,
4-Q |
D) 1-U, 2-R, 3-S,
4-Q |
|
|
|
| Correct Answer |
C |
|
| 2 |
A causal LTI system is described by the difference equation
2y[n] = ay[n-2] - 2x[n] + bx[n-1]
The system is stable only if
|
| Options |
A) | a | = 2, |
b | < 2
|
B) | a | > 2, | b
| >2
|
C) | a | < 2, any
value of b
|
D) | b | <
2, any value of a |
|
|
|
| Correct Answer |
C |
|
| 3 |
The drain of an n-channel MOSFET is shorted to
the gate so that VGS = VDS. The threshold
voltage (VT) of MOSFET is 1 V. If the drain current (ID)
is 1 mA for VGS = 2V, then for VGS = 3V, ID
is |
| Options |
| A) 2 mA |
B) 3 mA |
| C) 9 mA |
D) 4 mA |
|
|
|
| Correct Answer |
D |
|
| 4 |
The first and the last critical frequency of an
RC-driving point impedance function must respectively be |
| Options |
| A) a zero and a pole |
B) a zero and a zero |
| C) a pole and a pole |
D) a pole and a zero |
|
|
|
| Correct Answer |
D |
|
| 5 |
A random variable X with uniform density in the
interval 0 to 1 is quantized as follows:
If 0 £ X £
0.3, xq = 0
If 0.3 £ X £ 1,
xq = 0.7
where xq is the quantized value of X.
The root-mean square value of the quantization noise is |
| Options |
| A) 0.573 |
B) 0.198 |
| C) 2.205 |
D) 0.266 |
|
|
|
| Correct Answer |
A |
|
| 6 |
In a full-wave rectifier using two ideal
diodes, Vdc and Vm are the dc and peak values
of the voltage respectively across a resistive load. If PIV is the
peak inverse voltage of the diode, then the appropriate
relationships for this rectifier are
|
| Options |
| A)
Vdc =
, PIV = 2Vm |
B) Vdc = 2
, PIV = 2Vm |
| C) Vdc = 2
, PIV = Vm |
D) Vdc =
, PIV = Vm |
|
|
|
| Correct Answer |
B |
|
| 7 |
Choose the function f(t); -¥
< t < ¥, for which a Fourier
series cannot be defined. |
| Options |
| A) 3 sin (25 t) |
B) 4 cos (20 t + 3) + 2 sin (710 t) |
| C) exp(-|t| )sin(25t) |
D) 1 |
|
|
|
| Correct Answer |
C |
|
| 8 |
In what range should Re(s) remain so that the
Laplace transform of the function e(a+2)t+5 exits? |
| Options |
| A) Re (s) > a + 2 |
B) Re (s) > a + 7 |
| C) Re (s) < 2 |
D) Re (s) > a + 5 |
|
|
|
| Correct Answer |
A |
|
| 9 |
The state variable equations of a system are:
1. x1 = - 3x1 - x2 + u
2. x1 = 2x1
y = x1 + u
The system is
|
| Options |
| A) controllable but not observable |
B) observable but not controllable |
| C) neither controllable nor observable |
D) controllable and observable |
|
|
|
| Correct Answer |
D |
|
| 10 |
For the polynomial P(s) = s5 +
s4 + 2s3 + 2s2 + 3s + 15, the
number of roots which lie in the right half of the s-plane is
|
| Options |
|
|
|
| Correct Answer |
B |