.'

;;.

C\~~ G£:' S~fY1-y\\t - ET-p fYJCAy.- 2-Oq. ~ .' ~I\'--' ~ A-'v

"'" \'\ C '2 fYJ)G~\.Oav.~ I::'~b: 82 WIApnl-II t:7 V\f;I -;? . 01 ~ . J:;;> .I Con; 3030-11. - (REVISEDCOURSE) .

(3 Hours)

. 1. (a) Drawand explain inshort, test set up to measure signal to noise ratio.(b) With neat diagram, define (i) power gain (ii)available power gain (Hi)transducer

power gain (iv)transducer power gain in50 Q system, fortwo port amplifier.(c) What are the causes of lowfrequency noise and high frequency noise associated

withthe mixer?

(d) Defineand explainwithneat diagram noise correlation matrixfor general noisy twoport n.etwork.

~

;1

Zy\ 5)?J

RK-4752[ Total Marks: 100

N.S. : (1)(2)(3)(4)

Question NO.1 is compulsory.Make use of Z-Smith chart wherever necessary.Assume suitable data if required.Solve any four questions from remaining six questions.

55

5

5

2. (a) What are differenttechniques to obtain power amplifierlinearity? Drawand explain 10feed-forwardtechnique.

(b) Draw1t and T equivalentconfigurationof CE bipolartransistorwithnoise sources. 10Also give equations of mean square values of noise generator and noise powerspectral density due to noise sources, ina narrow frequency interval~f.

3. A GaAs FET is biased for minimum noise figure and has the followingS-parameters 20

and noise parameters at 4 GHz (20 =50 Q) : Sl1 =0'6 L -60°, S21 = 1.9 L 81°,

812 = 0,05 L 26°, 822= 0,5 L -60°; Fmin= 1.6 dB, rapt = 0.62 L 100°, RN= 20 Q. Fordesign purposes, assume the device is unilateral, and calculate the maximum error GTresulting from this assumption. Then, using microstrip matching network, design anamplifierhaving a 2'0 dB noise figurewiththe maximumgain that is compatible withthisnoise figure.

4. Design microstrip matching network for generating port and terminating port for a FET 20

transistor oscillator at 10 GHz. An inductor (LG=5 "H) is placed in series with the gate toincrease the positive feedback and thus increase further instability.The 8-parametersof the transistor have been converted from the common source into the common gateconfigurationand are given by-

8 =[

2.18L-35° 1'26L18°

]2.75 L 96° 0.52 L 155°

. [TURN OVER

83 WI April-II

Con. 3030-RK-4752-f1. 2

5. (a) Explainwith neat sketch dielectric resonator coupled to a microstrip.Also draw it's 10equivalentcircuit. '.

(b) Fora balanced mixerusingtwodiode and a 900hybridjunction,derive an expression 10for I.F. output current.. -. .

6. A GaAs MESFET has the followingS-parameters measured with a 50 Q resistance at 20. .

VOs == 4 V, IDS=0,9 loss at 9 GHz. Design the input and the output matching network for. maximumpower gain at 9 G'H~,as shown infigure below,using lumped elements.

~

[0.55 L -150° 0.04 L 2°°

][S]= 2 .82 L 180° 0.45 L - 30°

tv j)

5LL S SD...I1-

je,

Desired amplifier circuit.

7. Write short notes on:-

(a) Powerdistributed amplifier(b) Leeson's model for oscillator phase noise(c) Balanced amplifier using 900hybrid coupler.

776

2E s~- ~t\C ~1 -- mJ2~1- ?-C"~

b~ -- ~C\~Q-~ r" ~~, ~(REVISED COURSE)

1'~r~tq

21 : 1st half.11-AM(m)

Con. 3061-11. RK-4770

(3 Hours) [Total Marks: 100

N.B.: (1) Question No.1 is compulsory.(2) Answer any four out of remaining six questions.(3) Figures to the right indicate full marks.(4) Assume any suitable data if necessary.

1. Answer the following questions :-/

(a) Is the Huffman code optimal? Prove with an example.(b) Justify 'Quality of picture depends on the number of pixels and gray levels'.(c) Explain slant transform.(d) Justify! contradict 'For digital Image having salt and pepper noise, median

filter is the best'.

20

2. (a) Explain the following Image Enhancement Techniques with application :-(i) Intensity level slicing

(ii) Range Compression(iii) Edge detection'.

15

(b) Compare between contrast stretching and histogram equalization. 5

3. (a) A 8 level image is given below :-.

f (x,y) =10

Image

Prepare the histogram of the given image.Perform Histogram equalization and draw New Histogram.

(b) A source emits 8 symbols with the probabilities given :- 10

Obtain Huffman code and calculate entropy, average code word length and codingefficiency.

[ TURN OVER

4 6 O. 3 72 1 5 0 34 2 7 0 71 5 4 6 04 7 5 4 1

Symbol a1 a2 a3 a4 a5 a6 a7 a8Probability 0.1 0.4 0.05 0.05 0.1 0.2 0.07 0.03

/

22 : 1st half. 11-AM(m)

Con. 3061-RK-4770-11. 2

4. (a) Name different types of image segmentation techniques. Explain the splitting and 10merging tech~ique with the help of an example.

(b) Apply slant transform and OCT transform on the given image and compare the 10result.

f(x,y) =

Image

5. (a) What is Hadamard Transform? Write a 4 x 4 Hadamard matrix and its application. 10Is H(4) Orthogonal and Normalized.

(b) Apply Low and High Pass Spatial masks on the following image matrix. Prove 10that High Pass = Original - Lowpass. Assume virtual Rows and Columns.

f(x,y) =

Image

6. (a) Compare:-(i) Lossy and Lossless compressions.

(ii) Objective fidelity criteria and subjective fidelity criteria.(b) Explain segmentation based on discontinuity and segmentation

similarities.

10

based on 10

7. Write short notes on any four of the following :-(a) Haar Transform(b) Frequency domain filtering(c) Wiener Filtering(d) Spatial domain filtering(e) Connectivity of Pixels(f) Uniform and non-uniform sampling.

20

2 2 2 12 4 4 22 4 4 22 2 2 2

30 31 3233 120 3032 32 31

"'"22: 1st half. 11-AM(m)

Con. 3061-RK-4770-11. 2

4. (a) Name different types of image segmentation techniques. Explain the splitting and 10merging techr:1iquewith the help of an example.

(b) Apply slant transform and DCT transform on the given image and compare the 10result. \

f(x,y) =

Image

5. (a) What is HadamardTransform?Write a 4 x 4 Hadamardmatrixand its application. 10Is H(4) Orthogonal and Normalized.

(b) Apply Low and High Pass Spatial masks on the following image matrix. Prove 10that High Pass = Original - Lowpass. Assume virtual Rows and Columns.

f(x,y) =

Image

6. (a) Compare:-(i) Lossy and Lossless compressions.

(ii) Objective fidelity criteria and subjective fidelity criteria.(b) Explain segmentation based on discontinuity and segmentation

similarities.

10

based on 10

7. Write short notes on any four of the following :--(a) Haar Transform(b) Frequency domain filtering(c) Wiener Filtering(d) Spatial domain filtering(e) Connectivity of Pixels(f) Uniform and non-uniform sampling.

20

~

2 2 2 12 4 4 22 4 4 22 2 2 2

30 31 3233 120 3032 32 31

./

(.em ~ - 1i'~7c - M.~ ")",01).P4-Exam.-May-11-167If!"" ft .' " 0 ~c. .Con. 3165-11. . ~ ~ .- (OLDCOURSE) .

(3 Hours)

RK-3882[Total Marks: 100

L..;..~ t

N.S.: (1)Question No.1is compulsory. . ~,-"(2) Answer any four questions out of remaining six questions.

1. Answer the followingin brief :-(a) Discuss the basic block diagram of optical communication system.(b) What are direct and indirect band gap semiconductors? Which types are

. . suitable to be used as optical sources and detectors.(c) Howdoes the optical signal propagate through the fiber derive equations for numerical aperture.(d)What is the difference between homodyne and heterodyne detection?

20

2.(a) .Draw and explain the structure of Avalanche Photo Diode (APD) along with 10electrical field profilethat exist in the various regions of APD structure. Explain why it is also calledreach through APD (RAPD).(b) Discuss advantages of Optical fiber system over wired and wireless system. 10

3. (a) Explain anyone fiber fabrication process with a neat diagram.(b)'Explain with neat sketches fiber splicing techniques. State the desirable requirementsof a good fiber connector.

1010

4.(a) With necessary equations explain modulation electrical and optical bandwidth.Draw and Edge explain emitter double heterodyne LED structure. ",(b) Define LED power and efficiency with necessary derivations

1010

5. a) Explain the basic principle behind LASER and derive the Eienstein relation for spectral densityand ratio of stimulated emission rate versus spontaneous rate. . 10b) What arethe differentmaterialthat are usedfor fabricationof LASERfor differentwavelengths.Draw and explain STRIPE geometry DH injection LASER 10 .

6. (a) Explian the techniques for measurement of attenuation, dispersion, refractive index andnumericalapertureof a fiber. .(b) Discuss a popular non-destructive technique for attenuation measurement.

1010

7. Write short notes on ~ny four:-(a) Rise time budget(b) Link Power budget. .

(c) Radiative losses in optical fiber.(d) PIN diode '

(e) Optical receiver and noise sources 20

81, s~M" s. E T-. ACIJ"MMy".-z./)'! ~/'J IIVT.ApriJ..ll. 231 S~'-~ 5c.4&\""'''CoW\M\A". C-..; C4.t ~" -- ~Con. 3780"':'11. (REVISED COURSE) , RK-4755

, -;( 3 Hours)

N.S. : (1) Question No.1 is compulsory.(2) Attemptany four questions from remaining.(3) Assume suitable data ifnecessary.

[ Total Marks: 100

1. Answer the following :-(a) Why sate.llite communication is considered as 'distance insensitive

communication system' ? Compare sateUitecommunication system withoptical fibre communication system. '

(b) At the input to a receiver,the receivedcarrier power is 400 pwattsand

the system noise tem,perature is 450 k. Calculate (~) density ratio

in dBHz. Given that the bandwidth is 36 MHz, calculate (~) in dB,

(c) Defineand explainthe terms 'roll', 'pitch' and 'yaw'with respect to a satellite.Support your answerwith neat sketches. What do you mean by 'AntennaLook Angles'.

(d) Compare the major differences, advantages and disadvantages of FDMAand TDMA used in satellite communication.

20

2. (a) Explainin detailvarioustypesof satelliteorbits. How launchingof geostationary 8satellites is achieved?

(b) Explain what is meant by orthogonal polarisation and the importance of this 4in satellite communication"

(c) Describe the 'tracking, telemetry and command' subsystem of a satellite 8communication system.

3. (a) With a neatand labelleddiagram,explaindouble reflectorantennasand shaped 10reflector system.

(b) Derive the expression for Carrier-to-Noise-Ratio [~] of a satellite 10communication link.

Hence, solve the following :-In a satellite link, the propagation loss is 200 dB. Margins and other losses

account for another 3 dB. The receiver ~ is 11 dB and EIRP is 45 dBw.

Calculate the, received (C/N) for a system bandwidth of 36 MHz.

[ TURN OVER

"'"-- ".

,... . " .

VT-April.-ll- 232

Con. 3780-RK-4755-11. 2

4. (a) Describe the principles of operation of code division multiple access. What 10effect do the unwanted signals have on the wanted signal?

(a) With the aid of a block schematic,explainvarious elements of an earth station. 10Why is it desirable to place the low-noise amplifier of the antenna end ofthe feeder cable?

5. (a) Explainin detailvariousways of propagationimpairmentthat affect transmission 10of satellite sign(.lls.

(b). What impact the earth eclipse of satellite has on satellite communication? 10Explain in detail with the help of neat sketches.

6. (a) Explain in detail how electrical power requirement in a satellite is managed. 10

What are the different means of powersupply are adopted? .

(b) What are the main considerations in the design of an earth station? How 10design of small earth station is different from that of large earth stations?

7. Answer the following (any four) :-(a) Kepler's Laws of planetary motion(b) Limits of visibility(c) Intermodulation noise(d) Single spot, Global spot and multiple spot beam antenna(e) Frequency bands used for satellite communication.

20

***********

- . --

~,~) 'AGJ 1st half (x) 45

\">-'0- Pit \f

Con. 3988-11.

~ CR) "'2...', I ') f , I

ClJ,- . W~\~ ~ d-wd'i k .(REVISED COURSE) RK-4773

£~\G

(3 Hours) [Total Marks: 100

Note: 1 Question No.1 is compulso'1'2. Attempt any four questions from remaining six.3. Assume suitable data if necessary.4. Fi~ures to the right indicates full marks.

Q.1.

Q.2.

Q.3.

Q.4.

Q.5.

Q.6.

Q.7.

a) What is frequency reused in GSM? Explainb) Explain the concept of hidden exposed terminal in WLAN.c) Explain the security aspect of Bluetooth.d) Explain various WLAN topologies.

a) Explain forward link features of CDMA 2000 and also explainbasic services provided by upper layers of CDMA 2000.

b) Draw the block diagram and explain GSl\.1 architecture in detailindicating all the interfaces.

a) Explain Link budget analysis and requirements of Wirelessnetwork.

b) Draw network connection establishment flow in Bluetooth andexplain Park, Hold, and Sniff mode in detail.

a) Draw and explain W AP architecture in detail.b) Explain the following: i) Bluetooth protocol stack.

ii) Bluetooth application.

a) Explain logical channel hierarchy in GSM.b) Explain security aspect of GSM.c) Explain in detail Wireless sensor network.

a) Give the advantages, disadvantages, and applications of W AP.b) Explain the following: i) ZigBee technology.

ii) WIMAX.

Compare and contrast the following:a) GSM and CDMAb) IS-95 and CDMA 2000c) CDMA 2000 and WCDMA

---------------------

05050505

10

10

10

10

1010

060608

1010

20