PHE -16

ASSIGNMENT BOOKLET Bachelor's Degree Programme (B.Sc.)

COMMUNICATION

Valid from January 1, 2014 to December 31, 2014

It is compulsory to submit the Assignment before filling in the Term-End Examination Form.

Please Note

• You can take electives (56 or 64 credits) from a minimum of TWO and a maximum of FOUR science disciplines, viz. Physics, Chemistry, Life Sciences and Mathematics.

• You can opt for elective courses worth a MINIMUM OF 8 CREDITS and a MAXIMUM OF 48 CREDITS from any of these four disciplines.

• At least 25% of the total credits that you register for in the elective courses from Life Sciences, Chemistry and Physics disciplines must be from the laboratory courses. For example, if you opt for a total of 64 credits of electives in these 3 disciplines, at least 16 credits out of those 64 credits should be from lab courses.

• You cannot appear in the Term-End Examination of any course without

registering for the course. Otherwise, your result will not be declared and the responsibility will be yours.

School of Sciences Indira Gandhi National Open University Maidan Garhi, New Delhi-110068

(2014) Dear Student,

We hope you are familiar with the system of evaluation to be followed for the Bachelor’s Degree Programme. At this stage you may probably like to re-read the section on assignments for Elective Courses in the Programme Guide that we sent you after your enrolment. A weightage of 30 per cent, as you are aware, has been earmarked for continuous evaluation, which would consist of one tutor-marked assignment (TMA) for this course. Submit your assignment response at your Study Centre.

Instructions for Formatting Your Assignments

Before attempting the assignment please read the following instructions carefully:

1) On top of the first page of your TMA answer sheet, please write the details exactly in the following format:

ENROLMENT NO. : ………………………………………

NAME : ………………………………………

ADDRESS : ………………………………………

………………………………………

……………………………………… COURSE : …………………………….. COURSE TITLE : ……………………….……. ASSIGNMENT NO. : ………………………….… STUDY CENTRE : ………………………..……. DATE : ….……………………………...……

PLEASE FOLLOW THE ABOVE FORMAT STRICTLY TO FACILITATE EVALUATION AND TO AVOID DELAY.

2) Use only foolscap size paper (but not of very thin variety) for writing your answers. 3) Leave 4 cm margin on the left, top and bottom of your answer sheet. 4) Your answers should be precise and in your own words. Do not copy answers from study material. 5) While solving problems, clearly indicate the question number along with the part being solved. Write units at each step of your calculations as done in the text because marks will be deducted for such mistakes. Take care of significant digits in your work. Recheck your work before submitting it. 6) This assignment will remain valid from January 1, 2014 to December 31, 2014. However, you are advised to submit it within 12 weeks of receiving this booklet to accomplish its purpose as a teaching- tool.

We strongly recommend that you should retain a copy of your assignment response to avoid any unforeseen situation. If possible, please attach a photocopy of this assignment along with your response.

You could obtain response to the difficulties you may face in PHE-16 course via e-mail by writing to [email protected] . Please note that, we do not provide answers to Assignment questions.

We wish you good luck.

2 Tutor Marked Assignment PHE-16: Physics Course Code : PHE-16 Assignment Code: PHE-16/TMA/2014 Max. Marks: 100 Note: Attempt all questions. have their usual meanings. The marks for each question are indicated against it.

1. State with reasons whether the following statements are True or False. (2 ×10) i) Rise time of a pulse is the time required for the amplitude to reach from 0% to 100% of the peak amplitude value. ii) Standing wave ratio of a matched transmission line is zero. iii) Amplitude modulation index for dc modulating signal is 100%.

iv) Multipoint communication system in telephony is more efficient than point-to-point communication.

v) Though audio frequency range is 20 Hz to 20 kHz, the uses only 4 kHz bandwidth per channel, still the communication is audible.

vi) In superheterodyne receiver the local oscillator always operates at a fixed frequency. vii) Bandwidth of video amplifier of the monochrome receiver is narrower than that in the case of colour video amplifier. viii) Polarization discrimination technique doubles the bandwidth of the channel. ix) Token ring protocol suffers with the data collision problem.

x) The compact structure of OSI model makes data transfer efficient as compared to TCP/IP model. 2. a) What approach is followed in practice for the choice of a propagation medium for any communication system ? Why is a linear medium of propagation preferred? (4+1) b) Explain the procedure of stub matching in transmission lines. (5) 3. a) Calculate the noise power and noise voltage generated by a 1M Ω resistor at 37 °C over a 1 MHz bandwidth. (3+2) b) A dipole antenna of dl = 2m carries 20 A peak current at 200 MHz frequency. Calculate the radiation intensity in the side-on direction at a distance of 10 km. (5) 4. a) Explain the working of balance modulator for AM generation. State its advantages over a transformer coupled class-C amplifier based AM generator. (3 +2) b) Explain, how digital coding can help in overcoming the burst error noise in signal transmission. (5)

3 5. a) State the various techniques used for analog modulation of a digital signal carrier. How are they used for continuous wave transmission and two tone modulation systems? State the advantages of two tone modulation system. (2+2+1) b) In explain in detail the functions of base station and mobile switching centre. (5) 6. a) Explain the image frequency and double spotting phenomena in case of AM receivers. How can they be overcome? (3+2) b) Describe the working of a CCD camera. (5) 7. a) Explain the construction of a Schottky diode and state its advantages over normal p-n junction diode. (3+2) b) With an appropriate diagram, explain the construction of graded index multimode fibre. How does it reduce the modal dispersion? (3+2) 8. a) What is network security? Explain its types. (1+4) b) Compare the four types of network topologies on the basis of their configuration, reliability, cost and ruggedness. (5) 9. a) Describe the typical system configuration required for accessing the Internet via a service provider. (5) b) Compare the WAP architecture with OSI model. (5)

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4 TENTATIVE SCHEDULE FOR PHYSICS PROGRAMMES BROADCAST ON GYAN DARSHAN 1 January 2014 – December 2014

This is the tentative schedule for Physics students. The students may approach their cable operator to avail this facility.

Date/Day Time Slot Course Code Video Programme Title January 2014 05-01-14 9.00–9.30 pm PHE-15 Glimpses of the Cosmos (Sun) 12-01-14 9.00–9.30 pm PHE-02 Simple Harmonic Motion (Sun) 19-01-14 9.00–9.30 pm PHE-15 Exploring the Night Sky (Sun) 21-01-14 8.30-9.00 am PHE-02 Dolan (Tues) February 2014 02-02-14 9.00–9.30 pm PHE-15 On the Trail of Stars (Sun) 04-02-14 8.30-9.00 am PHE-06 Second Law of (Tues) 11-02-14 8.30-9.00 am PHE-02 Coupled Oscillations (Tues) March 2014 04-03-14 8.30-9.00 am PHE- 13 Introduction to Crystal Structure (Tues) 11-03-14 8.30-9.00 am PHE- 15 Astronomical Coordinates (Tues) 16-03-14 9.00–9.30 pm PHE- 10 Operational Amplifier (Sun) 18-03-14 8.30-9.00 am PHE- 06 Carnot Cycle (Tues) April 2014 06-04-14 9-00-9.30 pm PHE- 15 Astronomical Measurements (Measurement of (Sun) Distance and Brightness) 13-04-14 9-00-9.30 pm BPHE- 101 Rotating Frames of Reference (Sun) May 2014 11-05-14 9.00-9.30 pm PHE -15 Astronomical Measurements (Measurement of (Sun) Mass, Temperature and Time) 13-05-14 8.30-9.00 am PHE -10 Logic Gates (Tues)

5 Date/Day Time Slot Course Code Video Programme Title July 2014 06-07-14 9.00-9.30 pm PHE-04 Vector Calculus Part-I (Sun) 08-07-14 8.30-9.00 am BPHE-101 Exploring Physics: Experiments with Low cost (Tues) Materials 13-07-14 9.00-9.30 pm PHE-11 Matter Waves and the Uncertainty Principle (Sun) 20-07-14 9.00-9.30 pm PHE-11 Wave Particle Duality (Sun) 22-07-14 8.30-9.00 am BPHE-101 The Bicycle: A Vehicle for Teaching Physics (Tues) August 2014 05-08-14 8.30-9.00 am BPHE- 101 The Physics of Dance (Tues) 12-08-14 8.30-9.00 am PHE- 15 The Milky Way (Tues) 19-08-14 8.30-9.00 am PHE -04 Vector Calculus Part-II (Tues) 26-08-14 8.30-9.00 am PHE- 15 Stellar Spectra and Classification (Tues) September 2014 02-09-14 8.30-9.00 am PHE- 10 Digital Modulation (Tues) 07-09-14 9.00-9.30 am PHE -10 Amplitude Modulation (Sun) 09-09-14 8.30-9.00 am PHE- 06 First Law of Thermodynamics (Tues) October 2014 05-10-14 9.00–9.30 pm PHE-06 Applications of the First Law of Thermodynamics (Sun) 12-10-14 9.00–9.30 pm PHE-15 Stellar Structure (Sun) November 2014 09-11-14 9.00–9.30 pm PHE-10 Transistor Biasing (Sun) December 2014 14-12-14 9.00–9.30 pm PHE-06 Thermodynamics in Action (Sun) 16-12-14 8.30-9.00 am PHE-06 Ushmagatiki ke Anuprayog (Tues) 23-12-14 8.30-9.00 am PHE-10 Electronic Devices (Tues)

6 TENTATIVE SCHEDULE FOR PHYSICS STUDENTS ON DD1 (National Network) (January 2014 to November 2014) Time: 6.00 AM to 6.30 AM

Month/Date* Course Topic January 2014 PHE-13 Introduction to Crystal Structure 13-01-14 February 2014 BPHE-101 Ghurni Nirdesh Tantra (Hindi) 10-02-14 March 2014 PHE-15 The Milky Way 10-03-14 April 2014 PHE-10 Semiconductor Diode 14-04-14 May 2014 PHE-15 On the Trail of Stars 12-05-14 July 2014 PHE-10 Operational Amplifier 14-07-14 August 2014 PHE-02 Coupled Oscillations 11-08-14 September 2014 PHE-10 Transistor Configuration 08-09-14 October 2014 PHE-06 Thermodynamics in Action 13-10-14 November 2014 PHE-15 Exploring the Night Sky 10-11-14

* Second Monday of every month

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