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E192028 Pages:3

Draw the STS-1 frame format of SONET.

PART D

Answer any two full questions, each carries9 marks.
The carrier frequency and difference frequency of an MFSK signal are 250 kHz
and 25 KHz. Given that the number of different signal elements (M) is 8(L= 3
bits). Find out the different frequency assignments for each of the eight possible
3 bit data combinations.
Justify that the frequency spectrum of input signal will move to high frequency
bands by FDM process.
Explain any one analog data to analog signal encoding method with neat
waveform.
In a CDMA process two users are having the codes as given below.
115011: 1.1.1.1
115012: 1,-1,-1,1
Explain the data transmission process if user! wants to transmit a bit 0 and user2
wants to transmit a 0111.
Describe the two main distortions that can be occurred in a Delta modulated
waveform. How can it be avoided?

Differentiate statistical TDM and Synchronous TDM using suitable diagrams.

PART E
Answer any four full questions, each carries10 marks.

Which are the different types of error?

Explain asynchronous and synchronous data transmission modes with frame
structures?
Compare packet switching and circuit switching.

Describe the three phases in a circuit switching operation.

In a CRC error detecting scheme, choose divisor polynomial
ए: x ++ > + 1. Encode the bits 110101011.
What is hamming distance?

Explain the general model of spread spectrum in digital communication system.

How Frequency Hopping Spread Spectrum(FHSS) spreads the baseband signal
for transmission?

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