WorksheetsCS-II (22EC53) QUIZ-3
Total questions: 25
Worksheet time: 13mins
Name
Class
Date
1.
Number of parity bits in a (7,4) Hamming code is:
a)
1
b)
2
c)
3
d)
4
2.
A linear block code with parameters (n, k) has:
a)
n information bits
b)
k parity bits
c)
2^k codewords
d)
2^n codewords
3.
Syndrome S of received vector r is given by:
a)
rGᵀ
b)
rHᵀ
c)
HGᵀ
d)
Grᵀ
4.
A block code is linear if:
a)
Codewords are cyclic
b)
Sum of any two codewords is also a codeword
c)
Codewords are random
d)
Codewords have fixed parity
5.
The rate of an (n, k) code is:
a)
n/k
b)
k/n
c)
n−k
d)
1/(n−k)
6.
Minimum errors detectable =:
a)
dmin
b)
dmin − 1
c)
(dmin − 1)/2
d)
2dmin
7.
For dmin = 5, correctable errors =:
a)
1
b)
2
c)
3
d)
4
8.
Syndrome decoding detects:
a)
Data bits
b)
Error pattern
c)
Code rate
d)
Block size
9.
Dimension of H Matrix:
a)
k×n
b)
(n−k)×n
c)
n×k
d)
n×(n−k)
10.
In binary cyclic codes, g(x) divides:
a)
xⁿ
b)
xⁿ+1
c)
xⁿ−1
d)
1−xⁿ
11.
Degree of g(x) =:
a)
k
b)
n−k
c)
n+k
d)
nk
12.
Parity check polynomial =:
a)
g(x)+1
b)
reciprocal
c)
(xⁿ+1)/g(x)
d)
g(x)−1
13.
Cyclic shift = multiply by:
a)
x
b)
x²
c)
1/x
d)
−x
14.
Degree of h(x):
a)
n−k
b)
k
c)
n
d)
n+k
15.
A convolutional code described by:
a)
(n,k)
b)
(n,k,m)
c)
(k,m)
d)
(n,m)
16.
Trellis diagram shows:
a)
Polynomials
b)
State transitions
c)
Parity checks
d)
BER
17.
In Convolution encoding, Zero tail used to:
a)
Increase rate
b)
Return encoder to zero state
c)
Reduce distance
d)
Puncture
18.
Types of Spread Spectrum techniques:
a)
TDMA/FDMA
b)
DSSS/FHSS
c)
CDMA/OFDM
d)
FSK/PSK
19.
PN sequence is:
a)
Random
b)
Deterministic but noise-like
c)
All zeros
d)
Sine wave
20.
Autocorrelation helps in:
a)
Demodulation
b)
Synchronization
c)
Amplification
d)
Filtering
21.
DSSS spreads by:
a)
Multiplying with PN code
b)
Dividing by chip rate
c)
Adding noise
d)
Hop set
22.
FHSS works by:
a)
Multiplying
b)
Hopping frequency
c)
Reduce bandwidth
d)
Time slots
23.
Slow FHSS:
a)
One hop → many bits
b)
Many hops → one bit
c)
No hop
d)
Hop = chip rate
24.
DSSS modulation:
a)
AM
b)
FSK
c)
BPSK
d)
ASK
25.
Balance property:
a)
Equal zeros and ones
b)
Ones exceed zeros by 1
c)
All ones
d)
All zeros
100 %
