www.QuestionPaperDownload.com Code No: R05220503

R05

Set No. 2

II B.Tech II Semester Examinations,December 2010 PRINCIPLES OF COMMUNICATIONS Common to BME, IT, E.COMP.E, CSE, CSSE Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. Briefly discuss about the following error control techniques. (a) Linear block codes (b) Parity check bits (c) Convolutional codes.

[16]

2. Explain about the Sampling function and Sinc function.

[16]

3. Explain a method of frequency translation.

[16]

4. Show that an increase in the carrier amplitude A in FM has a noise-quenching affect. [16] 5. Three signals m1, m2, and m3 are to be multiplexed. m1 and m2 have a 5 kHz bandwidth, and m3 has a 10 kHz bandwidth. Design a commutator switching system so that each signal is sampled at its Nyquist rate. [16] 6. (a) Consider a noiseless channel with m input symbols and m output symbols show that H(x)=H(y) and H(y/x)=0 (b) Consider an AWGN channel with 4-KHz bandwidth and the noise power spectral density n/2 = 10−12 W/Hz. The signal power required at the receiver is 0.1 mW. Calculate the capacity of this channel. [8+8] 7. Discuss the principle of operation of ASK generator and ASK demodulator.

[16]

8. A signal band limited to 1MHz is sampled at a rate of 50% higher than Nyquist rate and quantized into 256 levels using a µ-law quantizer with µ=255. (a) Determine the signal to quantization noise ratio. (b) The SNR found in (i) was unsatisfactory It must be increased at least by 10dB.Would you be able to obtain the desired SNR without increasing the transmission bandwidth, if it was found that a sampling rate 20% above the Nquist rate is adequate. If so, explain how. What is the maximum SNR that can be realized in this way. [16] ?????

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R05

Set No. 4

II B.Tech II Semester Examinations,December 2010 PRINCIPLES OF COMMUNICATIONS Common to BME, IT, E.COMP.E, CSE, CSSE Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. (a) Consider a noiseless channel with m input symbols and m output symbols show that H(x)=H(y) and H(y/x)=0 (b) Consider an AWGN channel with 4-KHz bandwidth and the noise power spectral density n/2 = 10−12 W/Hz. The signal power required at the receiver is 0.1 mW. Calculate the capacity of this channel. [8+8] 2. Explain a method of frequency translation.

[16]

3. Show that an increase in the carrier amplitude A in FM has a noise-quenching affect. [16] 4. Explain about the Sampling function and Sinc function.

[16]

5. Briefly discuss about the following error control techniques. (a) Linear block codes (b) Parity check bits (c) Convolutional codes.

[16]

6. Discuss the principle of operation of ASK generator and ASK demodulator.

[16]

7. A signal band limited to 1MHz is sampled at a rate of 50% higher than Nyquist rate and quantized into 256 levels using a µ-law quantizer with µ=255. (a) Determine the signal to quantization noise ratio. (b) The SNR found in (i) was unsatisfactory It must be increased at least by 10dB.Would you be able to obtain the desired SNR without increasing the transmission bandwidth, if it was found that a sampling rate 20% above the Nquist rate is adequate. If so, explain how. What is the maximum SNR that can be realized in this way. [16] 8. Three signals m1, m2, and m3 are to be multiplexed. m1 and m2 have a 5 kHz bandwidth, and m3 has a 10 kHz bandwidth. Design a commutator switching system so that each signal is sampled at its Nyquist rate. [16] ?????

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R05

Set No. 1

II B.Tech II Semester Examinations,December 2010 PRINCIPLES OF COMMUNICATIONS Common to BME, IT, E.COMP.E, CSE, CSSE Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. Discuss the principle of operation of ASK generator and ASK demodulator.

[16]

2. Explain a method of frequency translation.

[16]

3. Show that an increase in the carrier amplitude A in FM has a noise-quenching affect. [16] 4. (a) Consider a noiseless channel with m input symbols and m output symbols show that H(x)=H(y) and H(y/x)=0 (b) Consider an AWGN channel with 4-KHz bandwidth and the noise power spectral density n/2 = 10−12 W/Hz. The signal power required at the receiver is 0.1 mW. Calculate the capacity of this channel. [8+8] 5. A signal band limited to 1MHz is sampled at a rate of 50% higher than Nyquist rate and quantized into 256 levels using a µ-law quantizer with µ=255. (a) Determine the signal to quantization noise ratio. (b) The SNR found in (i) was unsatisfactory It must be increased at least by 10dB.Would you be able to obtain the desired SNR without increasing the transmission bandwidth, if it was found that a sampling rate 20% above the Nquist rate is adequate. If so, explain how. What is the maximum SNR that can be realized in this way. [16] 6. Three signals m1, m2, and m3 are to be multiplexed. m1 and m2 have a 5 kHz bandwidth, and m3 has a 10 kHz bandwidth. Design a commutator switching system so that each signal is sampled at its Nyquist rate. [16] 7. Briefly discuss about the following error control techniques. (a) Linear block codes (b) Parity check bits (c) Convolutional codes.

[16]

8. Explain about the Sampling function and Sinc function.

[16]

?????

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www.QuestionPaperDownload.com Code No: R05220503

R05

Set No. 3

II B.Tech II Semester Examinations,December 2010 PRINCIPLES OF COMMUNICATIONS Common to BME, IT, E.COMP.E, CSE, CSSE Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. Show that an increase in the carrier amplitude A in FM has a noise-quenching affect. [16] 2. Briefly discuss about the following error control techniques. (a) Linear block codes (b) Parity check bits (c) Convolutional codes.

[16]

3. Discuss the principle of operation of ASK generator and ASK demodulator.

[16]

4. (a) Consider a noiseless channel with m input symbols and m output symbols show that H(x)=H(y) and H(y/x)=0 (b) Consider an AWGN channel with 4-KHz bandwidth and the noise power spectral density n/2 = 10−12 W/Hz. The signal power required at the receiver is 0.1 mW. Calculate the capacity of this channel. [8+8] 5. Three signals m1, m2, and m3 are to be multiplexed. m1 and m2 have a 5 kHz bandwidth, and m3 has a 10 kHz bandwidth. Design a commutator switching system so that each signal is sampled at its Nyquist rate. [16] 6. Explain about the Sampling function and Sinc function.

[16]

7. A signal band limited to 1MHz is sampled at a rate of 50% higher than Nyquist rate and quantized into 256 levels using a µ-law quantizer with µ=255. (a) Determine the signal to quantization noise ratio. (b) The SNR found in (i) was unsatisfactory It must be increased at least by 10dB.Would you be able to obtain the desired SNR without increasing the transmission bandwidth, if it was found that a sampling rate 20% above the Nquist rate is adequate. If so, explain how. What is the maximum SNR that can be realized in this way. [16] 8. Explain a method of frequency translation.

[16]

?????

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