dc
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Code No: 56026 :2: Set No. 4<br />
II Fill in the blanks<br />
11. Relative to Hard decision decoding, soft decision decoding results in _____________<br />
12. If T is the code vector and H is the Parity check Matrix of a Linear Block code, then the<br />
code is defined by the set of all code vectors for which H T .T = ______________<br />
13. The advantage of CDMA over Frequency hopping is ____________<br />
14. The Parity check matrix of a linear block code is<br />
1 0 1 1 0 0<br />
0 1 1 0 1 0<br />
1 1 0 0 0 1<br />
Its Hamming distance is ___________________<br />
15. The significance of PN sequence in CDMA is ________________<br />
16. The cascade of two Binary Symmetric Channels is a __________________________<br />
17. The source coding efficiency can be increased by using _______________________<br />
18. The advantage of Spread Spectrum Modulation schemes over other modulations is<br />
_________________<br />
19. Entropy coding is a _____________________<br />
20. A convolutional encoder of code rate 1/2 is a 3 stage shift register with a message word<br />
length of 6.The code word length obtained from the encoder ( in bits) is<br />
_____________<br />
-oOo-<br />
JNTUWORLD<br />
Code No: 07A5EC09 Set No. 1<br />
JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD<br />
III B.Tech. I Sem., I Mid-Term Examinations, September – 2010<br />
DIGITAL COMMUNICATIONS<br />
Objective Exam<br />
Name: ______________________________ Hall Ticket No.<br />
Answer All Questions. All Questions Carry Equal Marks.Time: 20 Min. Marks: 20.<br />
I Choose the correct alternative:<br />
1) Word length in Delta modulation in Delta modulation is [ ]<br />
A)3 bits B)2 bits C)1 bit D)2 n bits<br />
2) Which of the following gives minimum probability of error [ ]<br />
A)FSK B)ASK C)DPSK D)PSK<br />
3) QPSK is an example of M-ary data transmission with M= [ ]<br />
A)2 B)8 C)6 D)4<br />
4) The quantization error in PCM when Δ is the step size [ ]<br />
A) Δ 2 /12 B) Δ 2 /2 C) Δ 2 /4 D) Δ 2 /3<br />
5) Quantization noise occurs in [ ]<br />
A) TDM B)FDM C) PCM D)PWM<br />
6) Non Uniform quantization is used to make [ ]<br />
A) (S/N) q<br />
is uniform B) (S/N) q<br />
is non-uniform<br />
C) (S/N) q<br />
is high D) (S/N) q<br />
is low<br />
7) Slope Overload distortion in DM can be reduced by [ ]<br />
A) Increasing step size B)Decreasing step size<br />
C) Uniform step size D)Zero step size<br />
8) Which of the following requires more band width [ ]
Change language