1
GATE ECE 2014 Set 2
Numerical
+2
-0
The power spectral density of a real stationary random process X(t) is given by $$${S_x}\left( f \right) = \left\{ {\matrix{ {{1 \over W},\left| f \right| \le W} \cr {0,\left| f \right| > W} \cr } } \right.$$$

The value of the expectation $$$E\left[ {\pi X\left( t \right)X\left( {t - {1 \over {4W}}} \right)} \right]$$$
is ---------------.

Your input ____
2
GATE ECE 2014 Set 1
MCQ (Single Correct Answer)
+2
-0.6
Consider a random process $$X\left( t \right) = \sqrt 2 \sin \left( {2\pi t + \varphi } \right),$$ where the random phase $$\varphi $$ is uniformly distributed in the interval $$\left[ {0,\,\,2\pi } \right].$$ The auto - correlation $$E\left[ {X\left( {{t_1}} \right)X\left( {{t_2}} \right)} \right]$$ is
A
$$\cos \left( {2\pi \left( {{t_1} + {t_2}} \right)} \right)$$
B
$$\sin \left( {2\pi \left( {{t_1} - {t_2}} \right)} \right)$$
C
$$\sin \left( {2\pi \left( {{t_1} + {t_2}} \right)} \right)$$
D
$$\cos \left( {2\pi \left( {{t_1} - {t_2}} \right)} \right)$$
3
GATE ECE 2014 Set 1
Numerical
+2
-0
Let $$Q\left( {\sqrt y } \right)$$ be the BER of a BPSK system over an AWGN channel with two - sided noise power spectral density N0/2. The parameter 𝛾 is a function of bit energy and noise power spectral density. A system with two independent and identical AWGN channels with noise power spectral density N0/2 is shown in the figure. The BPSK demodulator receives the sum of outputs of both the channels GATE ECE 2014 Set 1 Communications - Random Signals and Noise Question 41 English

If the BER of this system is $$Q\left( {b\sqrt y } \right),$$ then the value of b is -----------.

Your input ____
4
GATE ECE 2013
MCQ (Single Correct Answer)
+2
-0.6
Bits 1 and 0 are transmitted with equal probability. At the receiver, the pdf of the respective received signals for both bits are as shown below. GATE ECE 2013 Communications - Random Signals and Noise Question 44 English

If the detection threshold is 1, the BER will be

A
$${1 \over 2}$$
B
$${1 \over 4}$$
C
$${1 \over 8}$$
D
$${1 \over 16}$$
GATE ECE Subjects
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
CBSE
Class 12