Fifth Semester B.E. Degree Examination, May/June 2010Telecom and Switching

a. Explain the working of a telephone transmitter circuitJ with suitable sketch. Derive anexpression for conversion of sound waves into AC signal and suppression of higherharmonics. (10 Marks)

b. What is side-tone? Describe the principal of operation of a anti-side tone circuit lwith thehelp of diagrams. (10 Marks)

a. Explain the basic functions that a switching system must perform.b. Explain with relevant diagram}aregister translater sender.c. Define: i) Grade of service ii) Time congestion iii) Call completion rate.

(08 Marks)(06 Marks)(06 Marks)

a. Explain how GaS in determined for OOSS systems in tandem. (06 Marks)b. Derive first Erlangs distribution formula clearly state the assumptions made. (10 Marks)c. On an average, one call arrives every 5 seconds during a period of 10 seconds. What is the

probability that,i) No call arrives?ii) One call arrives?iii) Two calls arrive?iv) More than two calls arrive? (04 Marks)

a. Design a two stage network to connect 12 incoming trunks to 9 outgoing trunks. (10 Marks)b. Calculate the number of cross-points for a 3 stage concentrator with M incoming and N

outgoing trunks given M>N. (10 Marks)

a. Explain the principle of operation of a time switch}with relevant diagram.b. Sketch and explain T-S-T switching network to connect M incoming

outgoing highways.

(10 Marks)highways to M

(10 Marks)

a. Explain the sequence of operations involved in call processing.b. Describe the processor architecture required in Stored Program Control (SPC).

(10 Marks)(10 Marks)

a. What is frame alignment with respect to PCM highways entering a digital exchange? How isit achieved? Explain with relevant diagrams. (10 Marks)

b. Explain the process of multi-framing in a 30 channel PCM signaling system. (10 Marks)

a. Explain the features of CCnT Na7 signaling system with the help of a block diagram andcompare it with the seven layer aSI model. (12 Marks)

b. Explain with block diagram, the architecture of intelligent network. (08 Marks)