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V.S.B. ENGINEERING COLLEGE, KARUR

Department of Electronics and Communication Engineering

Academic Year: 2016 – 2017 (EVEN Semester)

ASSIGNMENT QUESTIONS

S.No. YEAR /

SEMESTER

NAME OF THE SUBJECT PAGE NO.

1 I / II Semester Circuit Theory 2

2 I / II Semester Electronic Devices 6

3 II / IV Semester Electronic Circuits-II

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4 II / IV Semester Communication Theory 7

5 II / IV Semester Electromagnetic Fields 8

6 II / IV Semester Linear Integrated Circuits

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7 II / IV Semester Control System Engineering

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8 III / VI Semester Computer Networks 10

9 III / VI Semester Antenna and Wave

Propagation

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10 III / VI Semester Computer Architecture 11

11 III / VI Semester VLSI Design 12

12 III / VI Semester Medical Electronics 13

13 III / VI Semester Principles of Management 13

14 IV/VIII semester Wireless Communication 13

15 IV/VIII semester Wireless Networks 13

16 IV/VIII semester Data Converters 14

17 IV/VIII semester Ad Hoc and Sensor Networks 14

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Class: I Year / II Semester B.E. ECE ‘A’,‘B’ & ‘C’ Sections

Name of Subject: Circuit Theory

Name of Faculty member: Mr. S.Saravanan & R.Ashok Kumar

1. Find the current through each branch by network reduction technique.

2. Calculate a) the equivalent resistances across the terminals of the supply, b) total current

supplied by the source and c) power delivered to 16 ohm resistor in the circuit shown in figure.

3. In the circuit shown, determine the current through the 2 ohm resistor and the total

current delivered by the battery. Use Kirchhoff’s laws.

4. (i) Determine the current through 800 ohm resistor in the network shown in figure.

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(ii) Find the power dissipated in 10 ohm resistor for the circuit shown in figure.

5. (i) In the network shown below, find the current delivered by the battery.

(ii) Discuss about voltage and current division principles.

6. Calculate the resistance between the terminals A – B.

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7. i)Determine the value of V2 such that the current through the impedance (3+j4) ohm is Zero

ii) Find the current through branch a-b using mesh analysis shown in figure below.

8. Determine the mesh currents I1 and I2 for the given circuit shown below

9. Find the node voltages V1 and V2 and also the current supplied by the source for the circuit

shown below.

10. Find the nodal voltages in the circuit of figure.

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11. i) Using the node voltage analysis, find all the node voltages and currents in 1/3 ohm and 1/5

ohm resistances of figure.

ii) For the mesh-current analysis, explain the rules for constructing mesh impedance matrix and

solving the matrix equation [Z]I = V.

12. Solve for V1 and V2 using nodal method. Let V = 100V.

13. Using Mesh analysis, find current through 4 ohm resistor.

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14. Use nodal voltage method to find the voltages of nodes ‘m’ and ‘n’ and currents through j2

ohm and –j2 ohm reactance in the network shown below.

15. For the circuit shown find the current I flowing through 2 ohm resistance using loop analysis.

Class: I Year / II Semester B.E. ECE ‘A’,‘B’ & ‘C’ Sections

Name of Subject: Electronic Devices

Name of Faculty member: Mrs.V.Padmavathi, Ms.A.Agalya & Mr.T.Sivalingam

1. Calculate the built in potential barrier in a PN junction. Consider a silicon PN junction at

300K with doping densities NA = 1*108 cm

-3 and ND = 1*10

15 cm

-3. Assume ni = 1.5*10

10 cm

-3

2. A PN junction diode has at a temperature of 125˚C a reverse saturation current of 30 µA. At a

temperature of 125˚C find the dynamic resistance for 0.2 v bias in forward and reverse direction.

3. The h-parameter for the transistor are hie = 1.1 k, hfe =99, hre =2.5*10-4

and hoe = 25 µA/V.

Find the h-parameter for common base and common collector configuration.

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4. If a donor impurity is added to the extent of one atom per 108 germanium atoms, calculate its

resistivity at 300˚ K. If its resistivity without addition of impurity at 300˚ k is 44.64Ω, comparing

two values, comment on the result.

5. Consider a Si PN junction at T = 300˚ K with doping concentration of NA = 1016

cm-3

. Assume

the ni = 1.5*1010

cm-3

. Calculate the width of the space charge region in a PN junction, when a

reverse bias voltage VR = 5 V is applied.

Year/Semester & Branch: II/IV Semester & ECE ‘A’ &‘B’

Name of Subject: EC6401- Electronic Circuits-II

Name of Faculty member: Mr.S.Saravanan & Mr.T.Sivalingam

1. A newly constructed feedback amplifier undergoes a performance test with the following

results: With the feedback connection removed, a source signal of 2mV is required to

provide a 10 V output to the load; with the feedback connected, a 10 V output requires a

200 mV source signal. For this amplifier, indentify values of A, β, Aβ, closed loop gain,

and the amount of feedback in dB.

2. A Colpitts oscillator is designed with C1 = 100 pF and C2 = 7500 pF. The inductance is

variable. Determine the range of inductance values, if the frequency of oscillations is to

vary between 950 kHz to 2050 kHz.

3. Consider the design of an IF amplifier for an FM radio receiver. Using two synchronous

tuned stages with f0 = 10.7 MHz, find the 3-dB bandwidth of each stage so that the

overall bandwidth is 200 kHz. Using 3 µH inductors find C and R for each stage.

4. Design a Schmitt trigger circuit to have VCC = 12 V, UTP = 5 V, LTP = 3 V and IC = 2

mA, using two silicon NPN transistors with hFE(min) = 100 and I2 = 0.1 IC2.

5. Design a saturated collector coupled multivibrator for the following specifications: output

voltage 12 V peak; Output to be a positive pulse; the duration is 10 µs; the time

between pulses to be 20 µs. For the BJTs is used, hFE (min) = 100; ICBO = 0 and IC(ON) =

1 mA.

Year/Semester & Branch: II/IV Semester ECE ‘A’ & ‘B’

Name of Subject: Communication Theory

Name of Faculty member: S.Sri Shanmugapriya/A.Agalya

1. A transmitter radiates 10.125 kW with the unmodulated carrier of 9 kW. Calculate the

modulation index and percent of modulation. If another sine wave, corresponding to 40

percent modulation, is transmitted simultaneously determine the total radiated power?

2. A modulating signal 20 sin (2π x 103 t) is used to modulate a carrier signal 40sin (2π x 104

t).find out

(i) Modulation index

(ii) Percentage modulation

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(iii) Frequencies of the sideband components and their amplitudes

(iv) Bandwidth of the modulating signal

(v) Draw the spectrum of the AM wave

3. A 107.6 MHz carrier signal is frequency modulated by a 7 kHz sine wave. The resultant FM

signal has a frequency deviation of 50 kHz. Determine the following:

(i) the carrier swing of the FM signal

(ii) the highest and the lowest frequencies attained by the modulated signal.

(iii) the modulation index of the FM wave.

4. For a discrete memoryless source ‘S’ with 5 symbols S1, S2, S3, S4 ,S5 construct a Shannon

Fano code, Huffman code and also calculate any one of its efficiency if the probability

distribution is given as, P(S1)=0.4; P(S2)=0.15; P(S3)=0.15; P(,S4)=0.15; P(S5)=0.15

Year/Semester & Branch: II/IV Semester & ECE ‘A’ &‘B’

Name of Subject: Electromagnetic Fields

Name of Faculty member: Mrs.P.S.Gomathi & V.Padmavathi

1. A vector field is specified as G = 24xyax + 12(x2 + 2)ay + 18z2az. Given two points, P (1,

2, −1) and Q(−2, 1, 3), find: a) G at P b) a unit vector in the direction of G at Q c) a unit

vector directed from Q toward P d) the equation of the surface on which |G| = 60.

2. A parallel plate capacitor is filled with a non uniform dielectric characterized by

εr=2+2x106x

2, where x is the distance from on plate. If S=0.02m

2 and d=1mm, find C.

3. Let a filamentary current of 5 mA be directed from infinity to the origin on the positive z

axis and then back out to infinity on the positive x axis. Find H at P (0, 1, 0).

4. A toroidal core has a circular cross section of 4 cm2 area. The mean radius of the toroid is

6 cm. The core is composed of two semi-circular segments, one of silicon steel and the

other of a linear material with µR = 200. There is a 4mm air gap at each of the two joints,

and the core is wrapped by a 4000-turn coil carrying a dc current I1.

5. Let µ = 3 × 10−5 H/m, ε = 1.2 × 10−10 F/m, and σ = 0 everywhere. If H = 2 cos(1010

t −

βx)az A/m, use Maxwell’s equations to obtain expressions for B, D, E, and β.

Year/Semester & Branch: II/IV Semester & ECE ‘A’ &‘B’

Name of the Subject: Linear Integrated Circuits

Faculty Name: M.John Milton

1. In the figure shown, R1=10 kΩ, Rf=100kΩ, Vi=1V. A load of 25kΩ is connected to the

output terminal. Calculate (i) i1 (ii) vo (iii) iL and total current i0 into the output pin.

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2. A differential amplifier has a differential voltage gain of 2000 and a common mode gain

0f

0.2. Calculate the CMRR in dB.

3. Design a Widlar current source for generating a constant current I0 = 10µA. Assume VCC =

10V, VBE = 0.7 V, β = 125. Use VT = 25 mV.

4. In the figure shown, R1=5 kΩ, Rf=20 kΩ, Vi=1V. A load of 5kΩ is connected to the

output terminal. Calculate (i) Vo (ii) ACL (iii) iL (iv) the output current io indicating proper

direction of flow.

5. A non-inverting amplifier with a gain of 100 is nulled at 25οC. What will happen to the output

voltage if the temperature rises to 50οC for an offset voltage drift of 0.15 mV/

οC ?

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Year/Semester & Branch: II/IV Semester & ECE ‘A’ &‘B’

Name of Subject: EC 6405 - Control System Engineering

Name of Faculty member: R.Pari

1. Obtain Transfer function.

2. Find the transfer function using Mason’s formula

3. Derive the transfer function of armature controlled and field controlled DC motor.

4. Obtain C/R Using mason’s gain formula and Block diagram reduction technique.

CS6551 – COMPUTER NETWORKS

1. Explain what might happen if two stations are accidentally assigned the same hardware

address?

2. If sharing reduces cost, why are shared networks used only for local communication?

3. Why wireless LAN cannot use the same CSMA/CD mechanism that Ethernet uses?

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4. Complete given table and answer YES or NO.

Characteristic CSMA/CD CSMA/CA Token Ring

Multiple access

Carrier Sense

Collision checking

Acknowledgement

EC 6602 - ANTENNA AND WAVE PROPAGATION

1. Explain the numerical tools for designing the following antennas

i) Microstrip patch antenna

ii) Helical antenna

iii) Spiral antenna

CS6303 – COMPUTER ARCHITECTURE

Answer ALL Questions (2x10=20 Marks)

1. Assume a two address format specified as source, destination. Examine the following

sequence of instructions and explain the addressing modes used and the operation done in

every instruction.

(1) Move (R5)+, R0

(2) Add (R5)+,R0

(3) Move R0, (R5)

(4) Move 16(R5),R3

(5) Add #40, R5

2. Consider the computer with three instruction classes and CPI measurements as given

below and

Instruction counts for each instruction class for the same program from two different

compilers

are given. Assume that the computer’s clock rate is 4GHz. Which code sequence will

execute

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faster according to execution time?

Code from CPI for this Instruction class

A B C

CPI 1 2 3

Code from CPI for this Instruction class

A B C

Compiler 1 2 1 2

Compiler 2 4 1 1

EC6601 - VLSI DESIGN

Answer ALL Questions (2x10=20 Marks)

1. Consider the design of a CMOS compound OR-OR-AND-INVERT (OAI22) gate computing

F= (A+B). (C+D).

a) Sketch a transistor level schematic

b) Sketch a stick diagram

c) Estimate the area from the stick diagram

d) Layout your gate with a CAD tool

e) Compare the layout size to the estimated area

2. Show that the current through two transistors in series equal to the current through a single

transistor of twice the length if the transistors are well described by the Shockely model.

Specifically show that IDS1 = IDS2 in the given diagram when the transistors are in their linear

region: VDS < VDD-Vt , VDD > Vt (this is also true in saturation). Hint: Express the currents of

the series transistors in terms of V1 and solve for V1.

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EC6001 – MEDICAL ELECTRONICS

Answer ALL Questions (2x10=20 Marks)

1. Explain in detail the different types of electrodes used in biomedical applications.

(i) Microelectrode.

(ii) Depth and needle electrode

2. Define EEG. With neat diagram explain the 21 electrode system for recording brain

potentials.

EC6001 – PRINCIPLES OF MANAGEMENT

Answer ALL Questions (2x10=20 Marks)

1. Case study on the difference between Japanese and US Management.

2. Impact of current IT in Management concept

EC 6801 - WIRELESS COMMUNICATION

2. An urban area has a population of 200 million residents. Three competing trunked mobile network

(system A,B and C) provide cellular service in this area. System A has 384 cells with 19 channels

each, system B has 98 cells with 57 channels each, and system C has 49 cells each with 100

channels. Find the number of users that can be supported at 2% blocking if each user averages 2

calls per hour at average call duration of 3 minutes. Assuming that all three trunked systems are

operated at maximum capacity, compute the percentage market penetration of each cellular

provider.

3. Explain in detail about the GSM (2G cellular) wireless communication standard.

EC 6802 - WIRELESS NETWORKS

1. Define BYOD (Bring Your Own Device). Explain the possible problems if we are

implemented BYOD integration in Colleges, How do you rectify it? Give the solutions.

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2. If a total of 33MHZ of bandwidth ia allocated to a particular FDD cellular telephone

system which uses two 25 kHZ simplex channels to provide full duplex voice and control

channels, compute no of channels available per cell if a system uses (a) 4-cell reuse, (b)

7-cell reuse (c) 12-cell reuse.If 1 Mhz of the allocated spectrum is dedicated to control

channels,determine an equitable distribution of control channels and voice channels in

each cell for each of three systems.

EC 6019 - DATA CONVERTERS

1. With necessary illustrations, explain the test Setup for measuring DAC distortion and

Noise.

2. Q2. Describe in detail about ADC Code transitions measuring techniques.

CS 6003 - AD HOC AND SENSOR NETWORKS

1. Why does TCP not perform well in adhoc wireless networks? What are the changes made

to traditional networks to suit adhoc networking environment.

2. What are the advantages of reservation based MAC protocols over contention based

MAC protocols? Compare and contrast IEEE 802.11a, IEEE 802.11b and IEEE 802.11g.