Solve any one question from Q.1(a,b,c) &Q.2(a,b,c)

1(a)
Derive the Expession for quantization error and signal to quantization noise ratio for a non-sinusoidal PCM system.

6 M

1(b)
Draw AT and T hierarchy multiplexing system and explain.

8 M

1(c)
Explain narrowband noise and represent a narrowband noise in terms in inphase and quadrature components.

6 M

2(a)
A delta modualtor system is designed to operate 5 times the Nyquist rate for a signal with 3KH

_{z}bandwidth. Determine the maximum amplitude of 1.2KHz input sinusoid for which a delta modualtor does not have slope overload. Quantizing step size size is 250mV. Derive the expression used.
6 M

2(b)
Ascrambler is shown in figure 1. design the corresponding scrambles. If a sequence. S= 101010100000111 is applied to the input of his scrambles, determine the output sequence T. Verify that if this T is applied to te input of the descrambles, the output is the sequence S.

!mage

!mage

8 M

2(c)
Explain classification random process with mathematical expressions.

6 M

Solve any one question from Q.3(a,b) &Q.4(a,b)

3(a)
Derive the expression of signal to noise ratio (S/N) of integrator and dump filter, explain its operation.

8 M

3(b)
A polar NRZ signal is applied at the input of matched filter. The binary 1 is represented by reactangular pulses of amplitude A and duration T and the binary 0 is represented by reactangular pulse of amplitude -A and duration T. Obtain the impulse reponse of the matched filter and sketch it.

8 M

4(a)
Derive the expression for signal to noise ratio and error probability of a mathced filter is the presence of white Gaussian noise.

8 M

4(b)
Explain Geometrical representation of signal and Gram-Schmitt procedure.

8 M

Solve any one question from Q.5(a,b) &Q.6(a,b)

5(a)
Derive the expression for error probability of BPSK receiver.

8 M

5(b)
Give the mathematical representation of QPSK signal. Draw the signal space diagram of QPSK signal. Write the expression of all the message points in the diagram and explain.

8 M

6(a)
Explain M-ary PSK transmitter and receiver with suitable block dirgam. What are the advantages of M-ary PSK over M-ary FSK?

8 M

6(b)
Binary data is transmitted using BPSK at a rate 2 Mbps over RF link having bandewidth 2 MHz. Find signal power required at receiver input so taht error probability is less than or equal to 10

^{-4. Assume noise PSD to be 10-10 watt/Hz. (Q(3.71)=10-4).}
8 M

Solve any one question from Q.7(a,b,c) &Q.8(a,b,c)

7(a)
What is PN sequence? Explain the three properties of PN sequence with the help of 4 stage shift register.

6 M

7(b)
Draw the block diagram of DSSS system transmitter and receives. Write functional names inside the block and iput signal for each block & explain.

6 M

7(c)
What are the multiple access techinques? Explain WODMA in detail.

6 M

8(a)
Explain DS-SS BPSK transmittes and receiver with suitable block diagram and derive the power spectral density of the same.

6 M

8(b)
Explain the following frequency hop spread spectrum with the help of relevent diagram.

i) Slow frequency hopping.

ii) Fast frequency hopping.

i) Slow frequency hopping.

ii) Fast frequency hopping.

6 M

8(c)
Design a three feedback shift register with proper taps to generate N=7 PN sequence. Dra the generator block and if the initial state of shift register is 100 (fromleft to right). Find the output sequence.

6 M

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