GATE Last Ten Years EC Question Papers

GATE 2011 ECE Question Paper With Solutions

GATE 2010 ECE Question Paper With Solutions

GATE 2009 ECE Question Paper With Solutions

GATE 2008 ECE Question Paper With Solutions

GATE 2007 ECE Question Paper With Solutions

GATE 2006 ECE Question Paper With Solutions

GATE 2005 ECE Question Paper With Solutions

GATE 2004 ECE Question Paper With Solutions

GATE 2003 ECE Question Paper With Solutions

GATE 2002 ECE Question Paper With Solutions

GATE 2001 ECE Question Paper With Solutions

Read more...

GATE 2001 Question Paper With Solutions

SECTION - A
1. This question consists of TWENTY-FIVE sub-questions (1.1 – 1.25) of ONE mark
each. For each of these sub-questions, four possible alternatives (A,B, C and D)
are given, out of which ONLY ONE is correct. Indicate the correct answer by
darkening the appropriate bubble against the question number on the left hand
side of the Objective Response Sheet (ORS). You may use the answer book
provided for any rough work, if needed.

1.5. The region of convergence of the z-transform of a unit step function is
(a) z > 1 (b) z < 1
(c) (Real part of z) > 0 (d) (Real part of z) < 0

1.7. MOSFET can be used as a
(a) current controlled capacitor (b) voltage controlled capacitor
(c) current controlled inductor (d) voltage controlled inductor

1.8. The effective channel length of a MOSFET in saturation decreases with increase in
(a) gate voltage (b) drain voltage
(c) source voltage (d) body voltage

1.10. The 2’s complement representation of –17 is
(a) 01110 (b) 01111 (c) 11110 (d) 10001

1.11. Consider the following two statements:
Statement 1: A stable multi-vibrator can be used for generating square wave.
Statement 2: B stable multi-vibrator can be used for storing binary information.
(a) Only statement 1 is correct
(b) Only statement 2 is correct
(c) Both the statements 1 and 2 are correct
(d) Both the statements 1 and 2 are incorrect

1.13. An 8085 microprocessor based system uses a 4K × 8-bit RAM whose starting
address is AA00. The address of the last byte in this RAM is
(a) 0FFFH (b) 1000 H (c) B9FF H (d) BA00 H

15. If the characteristic equation of a closed-loop system is
s2+2S+2= 0 , then the system is
(a) over damped (b) critically damped
(c) underdamped (d) undamped

1.19. A band limited signal is sampled at the Nyquist rate. The signal can be recovered
by passing the samples through
(a) an RC filter (b) an envelope detector
(c) a PLL
(d) an ideal low-pass filter with appropriate bandwidth

1.21. If a signal f(t) has energy E, the energy of the signal f(2t) is equal to
(a) E (b)E/2 (c) 2E (d) 4E

1.22. A transmission line is distortion-less if
(a)RL=1/GC (b) RL = GC (c) LG = RC (d) RG = LC

1.24. The phase velocity of waves propagating in a hollow metal waveguide is
(a) greater than the velocity of light in free space.
(b) less than the velocity of light in free space.
(c) equal to the velocity of light in free space.
(d) equal to the group velocity.

1.25. The dominant mode in a rectangular waveguide is TE10, because this mode has
(a) no attenuation (b) no cut-off
(c) no magnetic field component (d) the highest cut-off wavelength

2. This question consists of TWENTY-FIVE sub-questions (2.1 – 2.25) of TWO marks
each. For each of these sub-questions, four possible alternatives (A, B, C and D)
are given, out of which ONLY ONE is correct. Indicate the correct answer by
darkening the appropriate bubble against the question number on the left hand
side of the Objective Response Sheet (ORS). You may use the answer book
provided for any rough work, if needed.

2.18 A video transmission system transmits 625 picture frames per second. Each
frame consists of a 400 × 400 pixel grid with 64 intensity levels per pixel. The
data rate of the system is
(a) 16 Mbps (b) 100 Mbps (c) 600 Mbps (d) 6.4 Gbps

2.22 A material has conductivity of 10-2 mho/m and a relative permittivity of 4. The
frequency at which the conduction current in the medium is equal to the
displacement current is
(a) 45 MHz (b) 90 MHz (c) 450 MHz (d) 900 MHz

2.23 A uniform plane electromagnetic wave incident normally on a plane surface of a
dielectric material is reflected with a VSWR of 3. What is the percentage of
incident power that is reflected?
(a) 10% (b) 25% (c) 50% (d) 75%

2.24 A medium wave radio transmitter operating at a wavelength of 492 m has a
tower antenna of height 124m. What is the radiation resistance of the antenna?
(a) 25Ω (b) 36.5Ω (c) 50Ω (d) 73Ω

SECTION – B
This section consists of TWENTY questions of FIVE marks each. Attempt ANY FIFTEEN
questions. Answers must be given in the answer book provided.

Click Here for Download Paper

Read more...

GATE 2002 ECE Question Paper

SECTION – A (75 marks)
1. This question consists of TWENTY-FIVE sub-questions (1.1 – 1.25) of ONE mark
each. For each of these sub-questions, four possible alternatives (A,B, C and D)
are given, out of which ONLY ONE is correct. Indicate the correct answer by
darkening the appropriate bubble against the question number on the left hand
side of the Objective Response Sheet (ORS). You may use the answer book
provided for any rough work, if needed

1.3 Convolution of x(t + 5) with impulse function δ(t – 7) is equal to
(a) x(t - 12) (b) x(t + 12) (c) x(t - 2) (d) x(t + 2)

1.4 Which of the following cannot be the Fourier series expansion of a periodic
signal?
(a) x(t) = 2cos t + 3 cos 3t (b) x(t) = 2cos πt + 7 cos t
(c) x(t) = cos t + 0.5 (d) x(t) = 2cos 1.5πt + sin 3.5 πt

1.6 In a negative feedback amplifier using voltage-series (i.e. voltage-sampling
series mixing) feedback. (Ri and Ro denote the input and output resistance
respectively)
(a) Ri decreases and Ro decreases (b) Ri decreases and Ro increases
(c) Ri increases and Ro decreases (d) Ri increases and Ro increases

1.7 A 741-type op-amp has a gain-bandwidth product of 1 MHz. A non-inverting
amplifier using this op-amp and having a voltage gain of 20 dB will exhibit a 3-dB
bandwidth of
(a) 50 KHz (b) 100 KHz (c)1000/17 KHz (d) 1000/7.07

1.9 4-bit 2’s complement representation of a decimal number is 1000. The number is
(a) +8 (b) 0 (c) -7 (d) -8

1.11 The number of comparators required in a 3-bit comparator type ADC is
(a) 2 (b) 3 (c) 7 (d) 8

1.18 A linear phase channel with phase delay TP and group delay Tg must have
(a) TP= Tg=constant (b) TP ∝f and Tg∝f
(c) TP = constant and Tg∝f (d) TP ∝f and Tg =constant

1.19. A 1 MHz sinusoidal carrier is amplitude modulated by a symmetrical square wave
of period 100µsec. Which of the following frequencies will NOT be present in the
modulated signal?
(a) 990 KHz (b) 1010 KHz (c) 1020 KHz (d) 1030 KHz

1.21. For a bit-rate of 8 Kbps, the best possible values of the transmitted frequencies
in a coherent binary FSK system are
(a) 16 KHz and 20 KHz (b) 20 KHz and 32 KHz
(c) 20 KHz and 40 KHz (d) 32 KHz and 40 KHz

1.22. The line-of-sight communication requires the transmit and receive antenna to
face each other. If the transmit antenna is vertically polarized, for best reception
the receive antenna should be
(a) horizontally polarized (b) vertically polarized
(c) at 45° with respect to horizontal polarization
(d) at 45° with respect to vertical polarization

1.23. The VSWR can have any value between
(a) 0 and 1 (b) -1 and +1 (c) 0 and ∞ (d) 1 and ∞
1.24. In an impedance Smith chart, a clockwise movement along a constant resistance
circle gives rise to
(a) a decrease in the value of reactance
(b) an increase in the value of reactance
(c) no change in the reactance value
(d) no change in the impedance value

1.25 The phase velocity for the TE10-mode in an air-filled rectangular waveguide is (c is the velocity of plane waves in free space)
(a) less than c (b) equal to c
(c) greater than c (d) none of the above

2. This question consists of TWENTY-FIVE sub-questions (2.1 – 2.25) of TWO marks
each. For each of these sub-questions, four possible alternatives (A,B, C and D)
are given, out of which ONLY ONE is correct. Indicate the correct answer by
darkening the appropriate bubble against the question number on the left hand
side of the Objective Response Sheet (ORS). You may use the answer book
provided for any rough work, if needed.

2.5. An amplifier using an opamp with a slew-rate SR = 1V/µsec has a gain of 40 dB.
If this amplifier has to faithfully amplify sinusoidal signals from dc to 20 KHz
without introducing any slew-rate induced distortion, then the input signal level
must not exceed.
(a) 795 mV (b) 395 mV (c) 79.5 mV (d) 39.5 mV

2.20. A signal x(t) = 100 cos(24π×103)t is ideally sampled with a sampling period of 50 µsec and then passed through an ideal low-pass filter with cutoff frequency of 15
KHz. Which of the following frequencies is/are present at the filter output?
(a) 12 KHz only (b) 8 KHz only
(c) 12 KHz and 9 KHz (d) 12 KHz and 8 KHz

2.25. A person with a receiver is 5 Km away from the transmitter. What is the distance that this person must move further to detect a 3-dB decrease in signal strength?
(a) 942 m (b) 2070 m (c) 4978 m (d) 5320 m

SECTION – B (75 Marks)
This section consists of TWENTY questions (EC3-EC22) of FIVE marks each. Attempt ANY
FIFTEEN questions. Answers must be given in the answer book provided. Answer for
each question must start on a fresh page and must appear at one place only. (Answers
to all parts of a question must appear together).

Click Here for Download The Question paper

Read more...

GATE 2003 ECE Question Paper

2. A source of angular frequency 1 rad/sec has a source impedance consisting of 1Ω
resistance in series with 1 H inductance. The load that will obtain the maximum
power transfer is
(a) 1 Ω resistance
(b) 1 Ω resistance in parallel with 1 H inductance
(c) 1 Ω resistance in series with 1 F capacitor
(d) 1 Ω resistance in parallel with 1 F capacitor

3. A series RLC circuit has a resonance frequency of 1 kHz and a quality factor Q =
100. If each R, L and C is doubled from its original value, the new Q of the circuit
is
(a) 25 (b) 50 (c) 100 (d) 200

6. n-type silicon is obtained by doping silicon with
(a) Germanium (b) Aluminum (c) Boron (d) Phosphorus

7. The bandgap of silicon at 300 K is
(a) 1.36 eV (b) 1.10 eV (c) 0.80 eV (d) 0.67 eV

9. Choose proper substitutes for X and Y to make the following statement correct
Tunnel diode and Avalanche photodiode are operated in X bias and Y bias
respectively.
(a) X: reverse, Y: reverse (b) X: reverse, Y: forward
(c) X: forward, Y: reverse (d) X: forward, Y: forward

10. For an n-channel enhancement type MOSFET, if the source is connected at a
higher potential than that of the bulk (i.e. VSB > 0), the threshold voltage VT of
the MOSFET will
(a) remain unchanged (b) decrease
(c) change polarity (d) increase

11. Choose the correct match for input resistance of various amplifier configurations
shown below.

Configuration Input resistance
CB: Common Base LO: Low
CC: Common Collector MO: Moderate
CE: Common Emitter HI: High
(a) CB-LO, CC-MO, CE-HI (b) CB-LO, CC-HI, CE-MO
(c) CB-MO, CC-HI, CE-LO (d) CB-HI, CC-LO, CE-MO

14. If the differential voltage gain and the common mode voltage gain of a
differential amplifier are 48 dB and 2 dB respectively, then its common mode
rejection ratio is
(a) 23 dB (b) 25 dB (c) 46 dB (d) 50 dB

15. Generally, the gain of a transistor amplifier falls at high frequencies due to the
(a) internal capacitances of the device
(b) coupling capacitor at the input
(c) skin effect
(d) coupling capacitor at the output

16. The number of distinct Boolean expression of 4 variables is
(a) 16 (b) 256 (c) 1024 (d) 65536

17. The minimum number of comparators required to build an 8 it flash ADC is
(a) 8 (b) 63 (c) 255 (d) 256

18. The output of the 74 series of TTL gates is taken from a BJT in
(a) totem pole and common collector configuration
(b) either totem pole or open collector configuration
(c) common base configuration
(d) common collector configuration

19. Without any additional circuitry, an 8:1 MUX can be used to obtain
(a) some but not all Boolean functions of 3 variables
(b) all function of 3 variables but none of 4 variables
(c) all functions of 3 variables and some but not all of 4 variables
(d) all functions of 4 variables

20. A 0 to 6 counter consists of 3 flip flops and a combination circuit of 2 input
gate(s). The combination circuit consists of
(a) one AND gate (b) one OR gate
(c) one AND gate and one OR gate (d) two AND gates

25. A PD controller is used to compensate a system. Compared to the
uncompensated system, the compensated system has
(a) a higher type number (b) reduced damping
(c) higher noise amplification (d) larger transient overshoot

26. The input to a coherent detector is DSB-SC signal plus noise. The noise at the
detector output is
(a) the in-phase component (b) the quadrature-component
(c) zero (d) the envelope

27. The noise at the input to an ideal frequency detector is white. The detector is
operating above threshold. The power spectral density of the noise at the output
is
(a) raised cosine (b) flat (c) parabolic (d) Gaussian

28. At a given probability of error, binary coherent FSK is inferior to binary coherent
PSK by
(a) 6 dB (b) 3 dB (c) 2 dB (d) 0 dB

29. The unit of ∇ × H is
(a) Ampere (b) Ampere/meter
(c) Ampere/meter2
(d) Ampere-meter

30. The depth of penetration of electromagnetic wave in a medium having
conductivity σ at a frequency of 1 MHz is 25 cm. The depth of penetration at a
frequency of 4 MHz will be
(a) 6.25 cm (b) 12.50 cm (c) 50.00 cm (d) 100.00 cm

31. Twelve 1Ω resistances are used as edges to form a cube. The resistance between
two diagonally opposite corners of the cube is
(a)5/6Ω (b)1/6Ω (c) 6/5Ω (d)3/2Ω

40. Match items in Group 1 with items in Group 2, most suitably.

Group 1 Group 2
P LED 1 Heavy doping
Q Avalanche photodiode 2 Coherent radiation
R Tunnel diode 3 Spontaneous emission
S LASER 4 Current gain
(a) P – 1 Q – 2 R – 4 S - 3 (b) P – 2 Q – 3 R – 1 S - 4
(c) P – 3 Q – 4 R – 1 S - 2 (d) P – 2 Q – 1 R – 4 S - 3

41. At 300 K, for a diode current of 1 mA, a certain germanium diode requires a
forward bias of 0.1435V, whereas a certain silicon diode requires a forward bias
of 0.718V. Under the conditions stated above, the closest approximation of the
ratio of reverse saturation current in germanium diode to that in silicon diode is
(a) 1 (b) 5 (c) 4 × 10000 (d) 8 × 10000

43. When the gate-to-source voltage (VGS) of a MOSFET with threshold voltage of
400mV, working in saturation is 900 mV, the drain current in observed to be 1
mA. Neglecting the channel width modulation effect and assuming that the
MOSFET is operating at saturation, the drain current for an applied VGS of 1400
mV is
(a) 0.5 mA (b) 2.0 mA (c) 3.5 mA (d) 4.0 mA

44. If P is Passivation, Q is n-well implant, R is metallization and S is soruce/drain diffusion, then the order in which they are carried out in a standard n-well CMOS fabrication process, is
(a) P-Q-R-S (b) Q-S-R-P (c) R-P-S-Q (d) S-R-Q-P

45. An amplifier without feedback has a voltage gain of 50, input resistance of 1 KΩ
and output resistance of 2.5 KΩ. The input resistance of the current-shunt
negative feedback amplifier using the above amplifier with a feedback factor of
0.2, is
(a) 1/11KΩ (b)1/5KΩ (c) 5 KΩ (d) 11 KΩ

49. The action of a JFET in its equivalent circuit can best be represented as a
(a) Current Controlled Current Source
(b) Current Controlled Voltage Source
(c) Voltage Controlled Voltage Source
(d) Voltage Controlled Current Source

51. Three identical amplifiers with each one having a voltage gain of 50, input
resistance of 1 KΩ and output resistance of 250Ω, are cascaded. The open circuit
voltage gain of the combined amplifier is
(a) 49 dB (b) 51 dB (c) 98 dB (d) 102 dB

52. An ideal sawtooth voltage waveform of frequency 500 Hz and amplitude 3V is
generated by charging a capacitor of 2 µF in every cycle. The charging requires
(a) constant voltage source of 3 V for 1 ms
(b) constant voltage source of 3 V for 2 ms
(c) constant current source of 3 mA for 1 ms
(d) constant current source of 3 mA for 2 ms

55. A 4 bit ripple counter and a 4 bit synchronous counter are made using flip-flops
having a propagation delay of 10 ns each. If the worst case delay in the ripple
counter and the synchronous counter be R and S respectively, then
(a) R = 10 ns, S = 40 ns (b) R = 40 ns, S = 10 ns
(c) R = 10 ns, S = 30 ns (d) R = 30 ns, S = 10 ns

60. In an 8085 microprocessor, the instruction CMP B has been executed while the
content of the accumulator is less than that of register B. As a result
(a) Carry flag will be set but Zero flag will be reset
(b) Carry flag will be reset but Zero flag will be set
(c) Both Carry flag and Zero flag will be reset
(d) Both Carry flag and Zero flag will be set

61. Let X and Y be two statistically independent random variables uniformly
distributed in the ranges (-1,1) and (-2,1) respectively. Let Z = X + Y. then the
probability that [Z≤-2] is
(a) zero (b)1/6 (c)1/3 (d)1/12

81. The input to a linear delta modulator having a step-size = 0.628 is a sine wave with frequency fm and peak amplitude Em. If the sampling frequency fs = 40 kHz,
the combination of the sine-wave frequency and the peak amplitude, where slope
overload will take place is
Em fm
(a) 0.3 V 8 kHz
(b) 1.5 V 4 kHz
(c) 1.5 V 2 kHz
(d) 3.0 V 1 kHz

82. If S represents the carrier synchronization at the receiver and ρ represents the bandwidth efficiency, then the correct statement for the coherent binary PSK is
(a) ρ = 0.5, S is required (b) ρ = 1.0, S is required
(c) ρ = 0.5, S is not required (d) ρ = 1.0, S is not required

83. A signal is sampled at 8 kHz and is quantized using 8-bit uniform quantizer.
Assuming SNRq for a sinusoidal signal, the correct statement for PCM signal with
a bit rate of R is
(a) R = 32 kbps, SNRq = 25.8 dB (b) R = 64 kbps, SNRq = 49.8 dB
(c) R = 64 kbps, SNRq = 55.8 dB (d) R = 32 kbps, SNRq = 49.8 dB

89. A rectangular metal wave-guide filled with a dielectric material of relative
permitivity εr = 4 has the inside dimensions 3.0cm×1.2cm. The cut-off frequency
for the dominant mode is
(a) 2.5 GHz (b) 5.0 GHz (c) 10.0 GHz (d) 12.5 GHz

Click Here For Download Question Paper

Read more...

GATE 2004 Electronics and Communication Engg Question Papers

6. The impurity commonly used for realizing the base region of a silicon n-p-n
transistor is
(a) Gallium (b) Indium (c) Boron (d) Phosphorus

7. If for a silicon n-p-n transistor, the base-to-emitter voltage (VBE) is 0.7V and the collector-to-base voltage (VCB) is 0.2V, then the transistor is operating in the
(a) normal active mode (b) saturation mode
(c) inverse active mode (d) cutoff mode

8. Consider the following statements S1 and S2.
S1: The β of a bipolar transistor reduces if the base width is increased.
S2: The β of a bipolar transistor increases if the doping concentration in the base
in increased
Which one of the following is correct?
(a) S1 is FALSE and S2 is TRUE (b) both S1 and S2 are TRUE
(c) both S1 and S2 are FALSE (d) S1 is TRUE and S2 is FALSE

9. An ideal op-amp is an ideal
(a) voltage controlled current source (b) voltage controlled voltage source
(c) current controlled current source (d) current controlled voltage source

10. Voltage series feedback (also called series shunt feedback) results in
(a) increase in both input and output impedances
(b) decrease in both input and output impedances
(c) increase in input impedance and decrease in output impedance
(d) decrease in input impedance and increase in output impedance

13. A master slave flip-flop has the characteristic that
(a) change in the input immediately reflected in the output
(b) change in the output occurs when the state of the master is affected
(c) change in the output occurs when the state of the slave is affected
(d) both the master and the slave states are affected at the same time

14. The range of signed decimal numbers that can be represented by 6-bite 1’s
complement number is
(a) -31 to +31 (b) -63 to +64 (c) -64 to +63 (d) -32 to +31

15. A digital system is required to amplify a binary-encoded audio signal. The user
should be able to control the gain of the amplifier from a minimum to a maximum
in 100 increments. The minimum number of bits required to encode, in straight
binary is
(a) 8 (b) 6 (c) 5 (d) 7

16. Choose the correct one from among the alternatives A,B,C,D after matching an
item from Group 1 with the most appropriate item in Group 2.

Group 1 Group 2
P. Shift register 1. Frequency division
Q. Counter 2. Addressing in memory chips
R. Decoder 3. Serial to parallel data conversion
(a) P – 3 Q – 2 R - 1 (b) P – 3 Q – 1 R - 2
(c) P – 2 Q – 1 R – 3 (d) P – 1 Q – 2 R - 2

22. The Fourier transform of a conjugate symmetric function is always
(a) imaginary (b) conjugate anti-symmetric
(c) real (d) conjugate symmetric

25. In a PCM system, if the code word length is increased from 6 to 8 bits, the signal to quantization noise ratio improves by the factor
(a)8/6 (b) 12 (c) 16 (d) 8

26. An AM signal is detected using an envelope detector. The carrier frequency and
modulating signal frequency are 1 MHz and 2 KHz respectively. An appropriate
value for the time constant of the envelope detector is
(a) 500 µsec (b) 20 µsec (c) 0.2 µsec (d) 1 µsec

27. An AM signal and a narrow-band FM signal with identical carriers, modulating
signals and modulation indices of 0.1 are added together. The resultant signal
can be closely approximated by
(a) broadband FM (b) SSB with carrier
(c) DSB-SC (d) SSB without carrier

28. In the output of a DM speech encoder, the consecutive pulses are of opposite
polarity during time interval t1≤t≤t2. This indicates that during this interval
(a) the input to the modulator is essentially constant
(b) the modulator is going through slope overload
(c) the accumulator is in saturation
(d) the speech signal is being sampled at the Nyquist rate

29. The phase velocity of an electromagnetic wave propagating in a hallow metallic
rectangular waveguide in the TE10 mode is
(a) equal to its group velocity
(b) less than the velocity of light in free space
(c) equal to the velocity of light in free space
(d) greater than the velocity of light in free space

30. Consider a lossless antenna with a directive gain of +6db. If 1mW of power is fed
to it the total power radiated by the antenna will be
(a) 4mW (b) 1mW (c) 7mW (d)1/4 mW

37. Consider the following statements S1and S2
S1: At the resonant frequency the impedance of a series R-L-C circuit is zero.
S2: In a parallel G-L-C circuit, increasing the conductance G results in increase in
its Q factor.
Which one of the following is correct?
(a) S1 is FALSE and S2 is TRUE (b) both S1 and S2 are TRUE
(c) S1 is TRUE and S2 is FALSE (d) both S1 and S2 are FALSE

41. Consider the following statements S1 and S2.
S1: The threshold voltage (VT) of a MOS capacitor decreases with increase in gate
oxide thickness
S2: The threshold voltage (VT) of a MOS capacitor decreases with increase in
substrate doping concentration.
Which one of the following is correct?
(a) S1 is FALSE and S2 is TRUE (b) both S1 and S2 are TRUE
(c) S1 is TRUE and S2 is FALSE (d) both S1 and S2 are FALSE

42. The drain of an n-channel MOSFET is shorted to the gate so that VGS = VDS. The
threshold voltage (VT) of MOSFET is 1V. If the drain current (ID) is 1 mA for VGS =
2V, then for VGS = 3V, ID is
(a) 2 mA (b) 3 mA (c) 9 mA (d) 4 mA

43. The longest wavelength that can be absorbed by silicon, which has the bandgap
of 1.12eV, is 1.1µm. If the longest wavelength that can be absorbed by another
material is 0.87 µm, then the bandgap of this material is
(a) 1.416 eV (b) 0.886 eV (c) 0.854 eV (d) 0.706 eV

50. In a full-wave rectifier using two ideal diodes, Vdc and Vm are the dc and peak
values of the voltage respectively across a resistive load. If PIV is the peak
inverse voltage of the diode, then the appropriate relationships for this rectifier
are

(a)Vdc=Vm/p PIV=2Vm (b)Vdc=2Vm/p PIV=2Vm
(c)Vdc=2Vm/p PIV=Vm (d)Vdc=Vm/p PIV=Vm

51. The minimum number of 2 to 1 multiplexers required to realize a 4 to 1
mutliplexer is
(a) 1 (b) 2 (c) 3 (d) 4

53. 11001, 1001 and 111001 correspond to the 2’s complement representation of
which one of the following sets of number?
(a) 25, 9 and 57 respectively (b) -6, -6 and –6 respectively
(c) -7, -7 and –7 respectively (d) -25, -9 and –57 respectively

54. The 8255 Programmable Peripheral Interface is used as described below.
I. An A/D converter is interfaced to a microprocessor through an 8255. the
conversion is initiated by a signal from the 8255 on Port C. A signal on Port C
causes data to be strobed into Port A.
II. Two computers exchange data using a pair of 8255s. Port A works as a bidirectional data port supported by appropriate handshaking signals.
The appropriate modes of operation of the 8255 for I and II would be
(a) Mode 0 for I and Mode 1 for II (b) Mode 1 for I and Mode 0 for II
(c) Mode 2 for I and Mode 0 for II (d) Mode 2 for I and Mode 1 for II

55. The number of memory cycles required to execute the following 8085 instructions
I. LDA 3000H
II. LXI D, FOF 1H
Would be
(a) 2 for I and 2 for II (b) 4 for I and 3 for II
(c) 3 for I and 3 for II (d) 3 for I and 4 for II

57. Consider the sequence of 8085 instructions given below.
LXI H, 9258 MOV A, M, CMA, MOV M, A
Which one of the following is performed by this sequence?
(a) contents of location 9258 are moved to the accumulator
(b) contents of location 9258 are compared with the contents of the accumulator
(c) contents of location 8529 are complemented and stored in location 8529
(d) contents of location 5892 are complemented and stored in location 5892

58. A Boolean function f of two variables x and y is defined as follows:
f(0,0) = f(0,1) = f(1,1)=1; f(1,0) = 0
Assuming complements of x and y are not available, a minimum cost solution for
realizing f using only 2-input NOR gates and 2-input OR gates (each having unit
cost) would have a total cost of
(a) 1 unit (b) 4 unit (c) 3 unit (d) 2 unit

60. A 1 kHz sinusoidal signal is ideally sampled at 1500 samples/sec and the sampled
signal is passed through an ideal low-pass filter with cut-off frequency 800 Hz.
The output signal has the frequency
(a) zero Hz (b) 0.75 kHz (c) 0.5 kHz (d) 0.25 kHz

75. A 1mW video signal having a bandwidth of 100 MHz is transmitted to a receiver
through a cable that has 40 dB loss. If the effective one-sided noise spectral
density at the receiver is 10-20 Watt/Hz, then the signal to noise ratio at the
receiver is
(a) 50 db (b) 30 db (c) 40 db (d) 60 db

77. Two sinusoidal signals of same amplitude and frequencies 10 kHz and 10.1 kHz
are added together. The combined signal is given to an ideal frequency detector.
The output of the detector is
(a) 0.1 kHz sinusoid (b) 20.1 kHz sinusoid
(c) a linear function of time (d) a constant

78. Consider a binary digital communication system with equally likely 0’s and 1’s.
When binary 0 is transmitted the voltage at the detector input can lie between
the level s-0.25V and +0.25V with equal probability: when binary 1 is
transmitted, the voltage at the detector can have any value between 0 and 1 V
with equal probability. If the detector has a threshold of 2.0V (i.e., if the received signal is greater than 0.2 V, the bit is taken as 1), the average bit error
probability is
(a) 0.15 (b) 0.2 (c) 0.05 (d) 0.5

81. Three analog signals, having bandwidths 1200 Hz, 600 Hz and 600 Hz, are
sampled at their respective Nyquist rates, encoded with 12 bit words, and time
division multiplexed. The bit rate for the multiplexed signal is
(a) 115.2 kbps (b) 28.8 kbps (c) 57.6 kbps (d) 38.4 kbps

89. A plane electromagnetic wave propagating in free space in incident normally on a
large slab of loss-less, non-magnetic, dielectric material with ε >ε0. Maxima and
minima are observed when the electric field is measured in front of the slab. The
maximum electric field is found to be 5 times the minimum field. The intrinsic
impedance of the medium should be
(a) 120 πΩ (b) 60 πΩ (c) 600 πΩ (d) 24 πΩ

90. A lossless transmission line is terminated in a load which reflects a part of the incident power. The measured VSWR is 2. the percentage of the power that is
reflected back is
(a) 57.73 (b) 33.33 (c) 0.11 (d) 11.11

Click Here for Download The Question Paper

Read more...

GATE 2005 EC Solved Paper

3.A fair dice is rolled twice. The probability that anodd number will follow an even
number is
a)1/2
(b)1/6
(c)1/3
(d)1/4

11. The band gap of Silicon at room temperature is:
(a) 1.3 eV (b) 0.7 eV (c) 1.1 eV (d) 1.4 eV

12. A Silicon PN junction at a temperature of 20°C has a reverse saturation current of 10 pico-Amperes (pA). The reverse saturation current at 40°C for the same bias
is approximately
(a) 30 pA (b) 40 pA (c) 50 pA (d) 60 pA

13. The primary reason for the widespread use of Silicon in semiconductor device
technology is
(a) abundance of Silicon on the surface of the Earth.
(b) larger bandgap of Silicon in comparison to Germanium.
(c) favorable properties of Silicon-dioxide (SiO2)
(d) lower melting point

14. The effect of current shunt feedback in an amplifier is to
(a) increase the input resistance and decrease the output resistance.
(b) increase both input and output resistances.
(c) decreases both input and output resistances.
(d) decrease the input resistance and increase the output resistance

16. The first and the last critical frequency of an RC-driving point impedance function
must respectively be
(a) a zero and a pole (b) a zero and a zero
(c) a pole and a pole (d) a pole and a zero

17. The cascode amplifier is a multistage configuration of
(a) CC-CB (b) CE-CB (c) CB-CC (d) CE-CC

18. Decimal 43 in Hexadecimal and BCD number system is respectively
(a) B2, 0100 0011 (b) 2B, 0100 0011
(c) 2B, 0011 0100 (d) B2, 0100 0100

24. Which of the following analog modulation scheme requires the minimum
transmitted power and minimum channel bandwidth?
(a) VSB (b) DSB-SC (c) SSB (d) AM

27. Despite the presence of negative feedback, control systems still have problems of
instability because the
(a) components used have nonlinearities.
(b) dynamic equations of the subsystems are not known exactly.
(c) mathematical analysis involves approximations.
(d) system has large negative phase angle at high frequencies.

30. Refractive index of glass is 1.5. Find the wavelength of a beam of light with a
frequency of 1014 Hz in glass. Assume velocity of light is 3×108 m/s in vacuum.
(a) 3 µm (b) 3 mm (c) 2 µm (d) 1 µm

36. Match the following and choose the correct combination:

Group 1 Group 2
E. Newton –Raphson method 1. Solving nonlinear equations
F. Runge-Kutta method 2. Solving linear simultaneous equations
G. Simpson’s Rule 3. Solving ordinary differential equations
H. Gauss elimination 4. Numerical integration
5. Interpolation
6. Calculation of Eigen values
(a) E – 6 F – 1 G – 5 H - 3 (b) E – 1 F – 6 G – 4 H - 3
(c) E – 1 F – 3 G – 4 H - 2 (d) E – 5 F – 3 G – 4 H - 1

45. A Silicon PN junction diode under reverse bias has depletion region of width 10
µm. The relative permittivity of Silicon,εr= 11.7 and the permittivity of free space
εd=8.85X10-12 f/m The depletion capacitance of the diode per square meter is
(a) 100 µF (b) 10 µF (c) 1 µF (d) 20 µF

56. The present output Qn of an edge triggered JK flip-flop is logic 0. If J=1, then Qn+1
(a) cannot be determined (b) will be logic 0
(c) will be logic 1 (d) will race around

69. A MOS capacitor made using p type substrate is in the accumulation mode. The
dominant charge in the channel is due to the presence of
(a) holes (b) electrons
(c) positively charged ions (d) negatively charged ions

73. A carrier is phase modulated (PM) with frequency deviation of 10 kHz by a single
tone frequency of 1 kHz. If the single tone frequency is increased to 2 kHz,
assuming that phase deviation remains unchanged, the bandwidth of the PM
signal is
(a) 21 kHz (b) 22 kHz (c) 42 kHz (d) 44 kHz


76. Characteristic impedance of a transmission line is 50 Ω.Input impedance of the
open circuited line is Zoc=100+j150Ω.When the transmission line is shortcircuited the value of the input impedance will be
(a) 50 Ω (b) 100 + j150Ω
(c) 7.69 + j11.54 Ω (d) 7.69 – j11.54

Click Here forSolved Paper

Read more...

GATE 2006 ECE Question Papes With Solutions

7. The values of voltage (VD ) across a tunnel-diode corresponding to peak and valley currents are and Vp and Vd respectively.The range of tunnel-diode voltage VD for which the slope of its I−Vd characteristics is negative would be
(A) VD< 0
(B) 0≤VD (C)Vp≤vD (D) VD≥Vv

8.The concentration of minority carriers in an extrinsic semiconductor under
equilibrium is:
(A) directly proportional to the doping concentration
(B) inversely proportional to the doping concentration
(C) directly proportional to the intrinsic concentration
(D) inversely proportional to the intrinsic concentration
9. Under low level injection assumption, the injected minority carrier current for an extrinsic semiconductor is essentially the
(A) diffusion current
(B) drift current
(C) recombination current
(D) induced current

10. The phenomenon known as “Early Effect” in a bipolar transistor refers to a
reduction of the effective base-width caused by
(A) electron-hole recombination at the base
(B) the reverse biasing of the base-collector junction
(C) the forward biasing of emitter-base junction
(D) the early removal of stored base charge during saturation-to-cutoff
switching.

20. A transmission line is feeding 1 Watt of power to a horn antenna having a gain of 10 dB. The antenna is matched to the transmission line. The total power radiated
by the horn antenna into the free-space is:
(A) 10 Watts
(B) 1 Watt
(C) 0.1 Watt
(D) 0.01 Watt

22. For the function of a complex Variable W=lnZ
where, W=u+jv Z= x+jy ), the u = constant lines get mapped in Z-plane
as
(A) set of radial straight lines
(B) set of concentric circles
(C) set of confocal hyperbolas
(D) set of confocal ellipses

32. The first and the last critical frequencies (singularities) of a driving point
impedance function of a passive network having two kinds of elements, are a
pole and a zero respectively. The above property will be satisfied by
(A) RL network only
(B) RC network only
(C) LC network only
(D) RC as well as RL networks

38. The majority carriers in an n-type semiconductor have an average drift velocity v
in a direction perpendicular to a uniform magnetic field B. the electric field E
induced due to Hall effect acts in the direction
(A) v × B
(B) B × v
(C) along v
(D) opposite to v

43. A new Binary Coded Pentary (BCP) number system is proposed in which every
digit of a base-5 number is represented by its corresponding 3-bit binary code.
For example, the base-5 number 24 will be represented by its BCP code 010100.
In this numbering system, the BCP code 100010011001 corresponds to the
following number in base-5 system
(A) 423
(B) 1324
(C) 2201
(D) 4231

61. A zero-mean white Gaussian noise is passed through an ideal lowpass filter of
bandwidth 10 kHz. The output is then uniformly sampled with sampling period
ts= 0.03 msec. The samples so obtained would be
(A) correlated
(B) statistically independent
(C) uncorrelated
(D) orthogonal

62. A source generates three symbols with probabilities 0.25, 0.25, 0.50 at a rate of 3000 symbols per second. Assuming independent generation of symbols, the
most efficient source encoder would have average bit rate as
(A) 6000 bits/sec
(B) 4500 bits/sec
(C) 3000 bits/sec
(D) 1500 bits/sec

Click Here for Download Question Paper

Read more...

GATE 2007 EC Question Paper

GATE 2007 ECE Question Paper

Q.1 – Q.20 Carry One Mark Each
Q.21 – Q.75 Carry Two Marks Each
Linked Answer Questions: Q.76 to Q.85 Carry Two Marks Each

10. In a P+ n junction diode under reverse bias, the magnitude of electric field is maximum at
(A) the edge of the depletion region on the p-side
(B) the edge of the depletion region on the n-side
(C) the p+ n junction
(D) the centre of the depletion region on the n-side

12. In a transconductance amplifier, it is desirable to have
(A) a large input resistance and a large output resistance
(B) a large input resistance and a small output resistance
(C) a small input resistance and a large output resistance
(D) a small input resistance and a small output resistance
13. X = 01110 and Y = 11001 are two 5-bit binary numbers represented in two’s
complement format. The sum of X and Y represented in two’s complement format
using 6 bits is:
(A) 100111 (B) 001000 (C) 000111 (D) 101001
14. The Boolean function Y AB CD = + is to be realized using only 2-input NAND
gates. The minimum number of gates required is:
(A) 2 (B) 3 (C) 4 (D) 5

21. It is given that X1,X2,.... Xm are M non-zero, orthogonal vectors. The dimension of the vector space spanned by the 2M vectors X1, X2.... Xm,-X1,-X2,...-Xm is:
(A) 2M (B) M + 1 (C) M
(D) dependent on the choice of X1,X2,... Xm

22. Consider the function F(x)=X2-X-2 The maximum value of f x( ) in the closed
interval [−4, 4] is:
(A) 18 (B) 10
(C) -2.25 (D) indeterminate

23. An examination consists of two papers, Paper 1 and Paper 2. The probability of
failing in Paper 1 is 0.3 and that in Paper 2 is 0.2. Given that a student has failed in Paper 2, the probability of failing in Paper 1 is 0.6. The probability of a student failing in both the papers is:
(A) 0.5 (B) 0.18 (C) 0.12 (D) 0.06

33. Group I lists four types of p-n junction diodes. Match each device in Group I with
one of the option in Group II to indicate the bias condition of that device in its
normal mode of operation.
Group I Group II
(P) Zener Diode (1) Forward bias
(Q) Solar cell (2) Reverse bias
(R) LASER diode
(S) Avalanche Photodiode
(A) P-1 Q-2 R-1 S-2 (B) P-2 Q-1 R-1 S-2
(C) P-2 Q-2 R-1 S-1 (D) P-2 Q-1 R-2 S-2

34. The DC current gain ( β ) of a BJT is 50. Assuming that the emitter injection
efficiency is 0.995, the base transport factor is:
(A) 0.980 (B) 0.985 (C) 0.990 (D) 0.995

35. Group I lists four different semiconductor devices. Match each device in Group I
with its characteristic property in Group II.
Group I Group II
(P) BJT (1) Population inversion
(Q) MOS capacitor (2) Pinch-off voltage
(R) LASER diode (3) Early effect
(S) JFET (4) Flat-band voltage
(A) P-3 Q-1 R-4 S-2 (B) P-1 Q-4 R-3 S-2
(C) P-3 Q-4 R-1 S-2 (D) P-3 Q-2 R-1 S-4

48. A Hilbert transformer is a
(A) non-linear system (B) non-causal system
(C) time-varying system (D) low-pass system

58. In delta modulation, the slope overload distortion can be reduced by
(A) decreasing the step size (B) decreasing the granular noise
(C) decreasing the sampling rate (D) increasing the step size

62. In a GSM system, 8 channels can co-exist in 200 KHz bandwidth using TDMA. A
GSM based cellular operator is allocated 5 MHz bandwidth. Assuming a frequency
reuse factor of 1/5 i.e. a five-cell repeat pattern, the maximum number of
simultaneous channels that can exist in one cell is:
(A) 200 (B) 40 (C) 25 (D) 5

64. An air-filled rectangular waveguide has inner dimensions of 3 cm × 2 cm. The
wave impedance of the TE20 mode of propagation in the waveguide at a frequency of 30 GHz is (free space impedance η0= Ω 377 )
(A) 308 Ω (B) 355 Ω (C) 400 Ω (D) 461 Ω

71. The gate oxide thickness in the MOS capacitor is:
(A) 50 nm (B) 143 nm (C) 350 nm (D) 1 µm

72. The maximum depletion layer width in silicon is
(A) 0.143 µm (B) 0.857 µm (C) 1 µm (D) 1.143 µm

73. Consider the following statements about the C-V characteristics plot:
S1: The MOS capacitor has an n-type substrate.
S2: If positive charges are introduced in the oxide, the C-V plot will shift to the
left. Then which of the following is true?
(A) Both S1 and S2 are true (B) S1 is true and S2 is false
(C) S1 is false and S2 is true (D) Both S1 and S2 are false

Click Here for Download The Paper

Read more...

GATE 2008 EC Question Paper

1 to 20 Carry One Mark Each

2. The system of linear equations
4x+ 2y= 7
2x+ y= 6

has
(A) a unique solution (B) no solution
(C) an infinite number of solutions (D) exactly two distinct solutions
3. The equation sin(z)= 10has
(A) no real or complex solution
(B) exactly two distinct complex solutions
(C) a unique solution
(D) an infinite number of complex solutions
4. For real values of x, the minimum value of the function f(x)= exp(x)+ exp(-x) is
(A) 2 (B) 1 (C) 0.5 (D) 0

10. The impulse response h(t) of a linear time-invariant continuous time system is
described by h(t)= exp(αt)u(t)+ exp(βt)(-ut)where u(t) denotes the unit step
function, and α and β are real constants. This system is stable if
(A) α is positive and β is positive (B) α is negative and β is negative
(C) α is positive and β is negative (D) α is negative and β is positive

13. Which of the following is NOT associated with a p-n junction?
(A) Junction capacitance (B) Charge Storage Capacitance
(C) Depletion Capacitance (D) Channel Length Modulation
14. Which of the following is true?
(A) A silicon wafer heavily doped with boron is a p+ substrate
(B) A silicon wafer lightly doped with boron is a p+ substrate
(C) A silicon wafer heavily doped with arsenic is a p+ substrate
(D) A silicon wafer lightly doped with arsenic is a p+ substrate
15. For a Hertz dipole antenna, the half power beam width (HPBW) in the E-plane is
(A) 360º (B) 180º (C) 90º (D) 45

18. A silicon wafer has 100nm of oxide on it and is inserted in a furnace at a
temperature above 1000ºC for further oxidation in dry oxygen. The oxidation
rate
(A) is independent of current oxide thickness and temperature
(B) is independent of current oxide thickness but depends on temperature
(C) slows down as the oxide grows
(D) is zero as the existing oxide prevents further oxidation

49. An 8085 executes the following instructions
2710 LXI H, 30A0H
2713 DAD H
2714 PCHL
All addresses and constants are in Hex. Let PC be the contents of the program
counter and HL be the contents of the HL register pair just after executing PCHL.
Which of the following statements is correct
(A) PC 2715H = (B) PC 30A0H = (C) PC 6140H = (D) PC 6140H =
HL 30A0H = HL 2715H = HL 6140H = HL 2715H

55. Consider the following assertions
S1: For Zener effect to occur, a very abrupt junction is required
S2: For quantum tunneling to occur, a very narrow energy barrier is required
Which of the following is correct?
(A) Only S2 is true
(B) S1 and S2 are both true but S2 is not a reason for S1
(C) S1 and S2 are both true and S2 is a reason for S1
(D) Both S1 and S2 are false

56. The two numbers represented in signed 2’s complement form are
P 11101101 and Q 11100110 = = . If Q is subtracted from P, the value obtained in
signed 2’s complement form is
(A) 100000111 (B) 00000111 (C) 11111001 (D) 11111100

61.A rectangular waveguide of internal dimensions (a 4cm and b 3 = = ) is to be
operated in TE11 mode. The minimum operating frequency is
(A) 6.25GHz (B) 6.0GHz (C) 5.0GHz (D) 3.75GHz
62. One of a loss-less transmission line having the characteristic impedance of 75Ω
and length of 1cm is short-circuited. At 3GHz, the input impedance at the other
end of the transmission line is
(A) 0 (B) Resistive (C) Capacitive (D) Inductive
63. A uniform plane wave in the free space is normally incident on an infinitely thick
dielectric slab (dielectric constant ε =
r 9 ). The magnitude of the reflection
coefficient is
(A) 0 (B) 0.3 (C) 0.5 (D) 0.8
64. In the design of a single mode step index optical fiber close to upper cut-off, the
single mode operations is NOT preserved if
(A) Radius as well as operating wavelength are halved
(B) Radius as well as operating wavelength are doubled
(C) Radius is halved and operating wavelength is doubled
(D) Radius is doubled and operating wavelength is halved
65. At 20GHz, the gain of a parabolic dish antenna of 1 meter diameter and 70%
efficiency is
(A) 15dB (B) 25dB (C) 35dB (D) 45dB
66. Noise with double-sided power spectral density of K over all frequencies is passed through a RC low pass filter with 3dB cut-off frequency of fc. The noise power at the filter output is
(A) K (B) Kfc (C) K fcπ (D) ∞
68. Four messages band limited to W, W, 2W and 3W respectively are to be
multiplexed using Time Division Multiplexing (TDM). The minimum bandwidth
required for transmission of this TDM signal is
(A) W (B) 3W (C) 6W (D) 7W

A speech signal, band limited to 4kHz and peak voltage varying between +5V and
-5V is sampled at the Nyquist rate. Each sample is quantized and represented by
8 bits.
71. If the bits 0 and 1 are transmitted using bipolar pulses, the minimum bandwidth
required for distortion free transmission is
(A) 64kHz (B) 32kHz (C) 8kHz (D) 4kHz
72. Assuming the signal to be uniformly distributed between its peak values, the
signal to noise ratio at the quantizer output is
(A) 16dB (B) 32dB (C) 48dB (D) 64dB

73. The number of quantitization levels required to reduce the quantization noise by
a factor of 4 would be
(A) 1024 (B) 512 (C) 256 (D) 64

Click Here for Solved Paper

Read more...

GATE 2012 Online Application Process

Application Process:

Step 1:Decide Payment Option
Gateway Payment:
Payment can be made using netbanking. Bank service charge is extra (maximum of Rs.30/-)

Challan Payment:
Payment by cash at ICICI, Indian Bank or State Bank of India branches. Bank service charge is extra (maximum of Rs.25/-)

Step 2: Obtain SC / ST / PD Certificate (if applicable)

Authorities empowered to issue Certificates

Step 3: Apply Online

Candidates must follow the instructions provided while applying online.

At the end of this process, a PDF file will be generated with the following pages:
Page-1: Instructions
Page-2: GATE 2012 Application - GATE Copy
Page-3: GATE 2012 Application - Candidate's Copy
Page-4: Address Slip of respective zonal GATE office
Page-5: Bank Challan (for Challan Payment option only)
Take a print out of the entire file on A4 size white sheets using a laser/inkjet printer.

Step 4: Cash Payment: (only for Challan Payment option)

The bank challan (Page-5) will be printed in triplicate. Take it to any one of the branches of ICICI, Indian Bank or State Bank of India (as opted by the candidate) and pay the fees. Bank will retain a copy and will return two copies to you. In those two copies, retain the Candidate's copy with you and attach the GATE Copy with the application.

Step 5:
Paste your recent photograph (3.5 cm X 3.5 cm) in the designated place of Page-2. Before pasting, please write your name and application number on the backside of the photo with black ball point pen.
Sign at the designated place of Page-2.
Paste Page-4 on top of a 10 inch x 12 inch size laminated envelope.

Step 6: Post/Submission
Before posting your application form, make sure that, in addition to the other relevant attachments, you have attached either a copy of the degree certificate or a certificate from your college principal as indicated below:
Candidates should submit a copy of the degree certificate or provisional certificate if they have passed their qualifying degree in 2011 or before.

Candidates with the following eligibility conditions should submit a certificate signed by the Principal of the college, where the candidate is studying, clearly indicating the year of passing of the candidate in the qualifying degree.

Students in the final year of Bachelor's degree programme in Engineering/Technology/ Architecture (4 years after 10+2).

Students in the final year of Bachelor's degree programme in Engineering/Technology/Architecture (Post-B.Sc./Post-Diploma).

Students in the final year of Master's degree programmes in any branch of Science/Mathematics/ Statistics/Computer Applications or equivalent.

Students in the second or higher year of the Four-year Integrated Master's degree programme (Post-B.Sc.) in Engineering/Technology.

Students in the fourth or higher year of Five-year Integrated Master's degree programme or Dual Degree programme in Engineering/Technology.

To download the format of the certificate to be sent by the candidates, click here.

Candidates With Backlog: Candidates with a backlog of papers should submit a copy of the marks sheet of final semester / final year or copy of the course completion certificate or a letter from the principal indicating that the student has a backlog and will be completing the degree in 2012.

Duly filled-in Application with appropriate enclosures must be sent by Speed Post (preferably) or by Registered Post to The Chairman, GATE of the Zone corresponding to the 1st Choice of Examination City, so as to reach on or before Monday, 24th October, 2011

OR

It can be handed over personally to the respective Zonal GATE Office on or before Monday, 24th October, 2011.

Read more...

GATE 2012 Online Application Status

GATE 2012 Online Application Status

The ONLINE application website will start from 00:00 hrs on 12 September 2011 and will close at 23:00 hrs on 17 October 2011

GATE 2012 - Application Status
Enter Application Number (7 digits)

(Only for the applications submitted to IIT Kanpur)

Click Here For GATE 2012 Online Application Status

Click Here For GATE 2012 Application Forms

Read more...

GATE 2009 Electronics and Communication Engg Paper

2. The Fourier series of a real periodic function has only
P. Cosine terms if it is even
Q. Sine terms if it is even
R. Cosine terms if it is odd
S. Sine terms if it is odd
Which of the above statements are correct?
(A) P and S (B) P and R (C) Q and S (D) Q and R

5.In an n-type silicon crystal at room temperature, which of the following can have
a concentration of 4 10 cm ?19−3
(A) Silicon atoms (B) Holes
(C) Dopant atoms (D) Valence electrons

6.The full form of the abbreviations TTL and CMOS in reference to logic families are
(A) Triple Transistor Logic and Chip Metal Oxide Semiconductor
(B) Tristate Transistor Logic and Chip Metal Oxide Semiconductor
(C) Transistor Transistor Logic and Complementary Metal Oxide Semiconductor
(D) Tristate Transistor Logic and Complementary Metal Oxide Silicon

16.In a microprocessor, the service routine for a certain interrupt starts from a fixed location of memory which cannot be externally set, but the interrupt can be delayed or rejected. Such an interrupt is

(A) non-maskable and non-vectored
(C) non-maskable and vectored
(B) maskable and non-vectored
(D) maskable and vectored

55.The amplitude of a random signal is uniformly distributed between -5V and 5V
If the signal to quantization noise ratio required in uniformly quantizing the signal is 43.5dB, the step size of the quantization is approximately

(A) 0.0333V
(B) 0.05V
(C) 0.0667V
(D) 0.10V

56.If the positive values of the signal are uniformly quantized with a step size of 0.05V, and the negative values are uniformly quantized with a step size of 0.1V, the resulting signal to quantization noise ratio is approximately

(A) 46dB
(B) 43.8dB
(C) 42dB
(D) 40dB

60.What are the minimum numbers of NOT gates and 2-input OR gates required to
design the logic of the driver for this 7-segment display?

(A) 3 NOT and 4 OR
(C) 1 NOT and 3 OR
(B) 2 NOT and 4 OR
(D) 2 NOT and 3 OR

Click Here Download ECE 2009 Paper

Read more...

GATE 2011 EC Solved Paper

3. An analog signal is band-limited to 4kHz, sampled at the Nyquist rate and the
samples are quantized into 4 levels. The quantized levels are assumed to be
independent and equally probable. If we transmit two quantized samples per
second, the information rate is ________ bits / second.
(A) 1 (B) 2 (C) 3 (D) 4
Answer: - (D)
Exp: - Since two samples are transmitted and each sample has 2 bits of information,
then the information rate is 4 bits/sec.

15. The Column-I lists the attributes and the Column-II lists the modulation
systems. Match the attribute to the modulation system that best meets it
Column-I Column-II
P Power efficient transmission of signals 1 Conventional AM
Q Most bandwidth efficient transmission of voice signals 2 FM
R Simplest receiver structure 3 VSB
S Bandwidth efficient transmission of signals with Significant dc component
4 SSB-SC
(A) P-4;Q-2;R-1;S-3 (B) P-2;Q-4;R-1;S-3
(C) P-3;Q-2;R-1;S-4 (D) P-2;Q-4;R-3;S-1
Answer: - (B)

57. Choose the most appropriate word from the options given below to complete the
following sentence: It was her view that the country's problems had been_________ by foreign technocrats, so that to invite them to come back would be
counter-productive.
(A) Identified (B) ascertained (C) Texacerbated (D) Analysed

Answer: - (C)
Exp: -The clues in the question are ---foreign technocrats did something negatively to the problems – so it is counter-productive to invite them. All other options are
non-negative. The best choice is exacerbated which means aggravated or
worsened.

58. Choose the word from the options given below that is most nearly opposite in
meaning to the given word:
Frequency
(A) periodicity (B) rarity
(C) gradualness (D) persistency
Answer: - (B)
Exp: - The best antonym here is rarity which means shortage or scarcity.
59. Choose the most appropriate word from the options given below to complete the
following sentence: Under ethical guidelines recently adopted by the
Indian Medical Association, human genes are to be manipulated only to
correct diseases for which______________ treatments are
unsatisfactory.
(A) Similar (B) Most (C) Uncommon (D) Available
Answer: - (D)
Exp: - The context seeks to take a deviation only when the existing/present/current/
alternative treatments are unsatisfactory. So the word for the blank should be a
close synonym of existing/present/current/alternative. Available is the closest of
all.

60. The question below consists of a pair of related words followed by four pairs of
words. Select the pair that best expresses the relation in the original pair:
Gladiator : Arena
(A) dancer : stage (B) commuter: train
(C) teacher : classroom (D) lawyer : courtroom
Answer: - (D)

65. The horse has played a little known but very important role in the field of
medicine. Horses were injected with toxins of diseases until their blood built up
immunities. Then a serum was made from their blood. Serums to fight with
diphtheria and tetanus were developed this way.
It can be inferred from the passage that horses were
(A) given immunity to diseases (B) generally quite immune to diseases
(C) given medicines to fight toxins (D) given diphtheria and tetanus serums

Answer: - (B)
Exp: - From the passage it cannot be inferred that horses are given immunity as in (A),
since the aim is to develop medicine and in turn immunize humans. (B) is correct
since it is given that horses develop immunity after some time. Refer “until their
blood built up immunities”. Even (C) is invalid since medicine is not built till
immunity is developed in the horses. (D) is incorrect since specific examples are
cited to illustrate and this cannot capture the essence.

Click Here for Download Gate 2011 EC Solved Paper

Read more...

GATE 2010 Electronics and Communication Engg (EC) Paper

Q. No. 1 – 25 Carry One Mark Each
1. The eigen values of a skew-symmetric matrix are
(A) always zero (B) always pure imaginary
(C) either zero or pure imaginary (D) always real
5. For parallel RLC circuit, which one of the following statements is NOT correct?
(A) The bandwidth of the circuit deceases if R is increased
(B) The bandwidth of the circuit remains same if L is increased
(C) At resonance, input impedance is a real quantity
(D) At resonance, the magnitude of input impedance attains its minimum value.
6. At room temperature, a possible value for the mobility of electrons in the inversion
layer of a silicon n-channel MOSFET is
(A) 450 cm2/V-s (B) 1350 cm2/V-s (C) 1800 cm2/V-s (D) 3600 cm2/V-s
7. Thin gate oxide in a CMOS process in preferably grown using
(A) wet oxidation (B) dry oxidation
(C) epitaxial deposition (D) ion implantation

Q. No. 26 – 51 Carry Two Marks Each
Q. No. 61 – 65 Carry Two Marks Each
61. Modern warfare has changed from large scale clashes of armies to suppression of
civilian populations. Chemical agents that do their work silently appear to be suited
to such warfare; and regretfully, there exist people in military establishments who
think that chemical agents are useful tools for their cause.
which of the following statements best sums up the meaning of the above
passage:
(A) Modern warfare has resulted in civil strife.
(B) Chemical agents are useful in modern warfare.
(C) Use of chemical agents in warfare would be undesirable.
(D) People in military establishments like to use chemical agents in war.
62. If 137+276=435 how much is 731+672?
(A) 534 (B) 1403 (C) 1623 (D) 1513
63. 5 skilled workers can build a wall in 20 days; 8 semi-skilled worker can build a wall
in 25days; 10 unskilled workers can build a wall in 30 days. If a team has 2 killed,
6 semi-skilled and 5 unskilled workers, how long will it take to build the wall?
(A) 20 days (B) 18 days (C) 16 days (D) 15 days
64. Given digits 2,2,3,3,3,4,4,4,4 how many distinct 4 digit numbers greater than
3000 can be formed?
(A) 50 (B) 51 (C) 52 (D) 54
65. Hari (H), Gita (G), Irfan (I) and Saira (S) are sibiligs (i.e. brothers and sisters). Allwere born on 1st January. The age difference between any two successive siblings(that is born one after another) is less than3 years. Given the following facts:
i. Hair’s age + Gita’s age > Irfan’s age + Saira’s age.
ii. The age difference between Gita and Saira is 1 year. However, Gita is not the
oldest and Saira is not the youngest.
iii. There are not twins.
In what order were they born (0ldest first)?
(A) HSIG (B) SGHI (C) IGSH (D) IHSG


Click Here for Download The EC 2010 Paper

Read more...

GATE Biotechnology(BT) Syllabus

GATE Syllabus For Biotechnology

Engineering Mathematics
Linear Algebra:
Matrices and determinants, Systems of linear equations, Eigen values and Eigen vectors.

Calculus:
Limit, continuity and differentiability, Partial derivatives, Maxima and minima, Sequences and series, Test for convergence, Fourier Series.

Differential Equations:
Linear and nonlinear first order ODEs, higher order ODEs with constant coefficients, Cauchy’s and Euler’s equations, Laplace transforms, PDE- Laplace, heat and wave equations.

Probability and Statistics:
Mean, median, mode and standard deviation, Random variables, Poisson, normal and binomial distributions, Correlation and regression analysis.

Numerical Methods:
Solution of linear and nonlinear algebraic equations, Integration of trapezoidal and Simpson’s rule, Single and multistep methods for differential equations.

Biotechnology

Microbiology:
Prokaryotic and eukaryotic cell structure; Microbial nutrition, growth and control; Microbial metabolism (aerobic and anaerobic respiration, photosynthesis); Nitrogen fixation; Chemical basis of mutations and mutagens; Microbial genetics (plasmids, transformation, transduction, conjugation); Microbial diversity and characteristic features; Viruses.

Biochemistry:
Biomolecules and their conformation; Ramachandran map; Weak inter-molecular interactions in biomacromolecules; Chemical and functional nature of enzymes; Kinetics of single substrate and bi-substrate enzyme catalyzed reactions; Bioenergetics; Metabolism (Glycolysis, TCA and Oxidative phosphorylation); Membrane transport and pumps; Cell cycle and cell growth control; Cell signaling and signal transduction; Biochemical and biophysical techniques for macromolecular analysis.

Molecular Biology and Genetics:
Molecular structure of genes and chromosomes; DNA replication and control; Transcription and its control; Translational processes; Regulatory controls in prokaryotes and eukaryotes; Mendelian inheritance; Gene interaction; Complementation; Linkage, recombination and chromosome mapping; Extrachromosomal inheritance; Chromosomal variation; Population genetics; Transposable elements, Molecular basis of genetic diseases and applications.

Process Biotechnology:
Bioprocess technology for the production of cell biomass and primary/secondary metabolites, such as baker’s yeast, ethanol, citric acid, amino acids, exo-polysacharides, antibiotics and pigments etc.; Microbial production, purification and bioprocess application(s) of industrial enzymes; Production and purification of recombinant proteins on a large scale; Chromatographic and membrane based bioseparation methods; Immobilization of enzymes and cells and their application for bioconversion processes. Aerobic and anaerobic biological processes for stabilization of solid / liquid wastes; Bioremediation.

Bioprocess Engineering:
Kinetics of microbial growth, substrate utilization and product formation; Simple structured models; Sterilization of air and media; Batch, fed-batch and continuous processes; Aeration and agitation; Mass transfer in bioreactors; Rheology of fermentation fluids; Scale-up concepts; Design of fermentation media; Various types of microbial and enzyme reactors; Instrumentation in bioreactors.

Plant and Animal Biotechnology:
Special features and organization of plant cells; Totipotency; Regeneration of plants; Plant products of industrial importance; Biochemistry of major metabolic pathways and products; Autotrophic and heterotrophic growth; Plant growth regulators and elicitors; Cell suspension culture development: methodology, kinetics of growth and production formation, nutrient optimization; Production of secondary metabolites by plant suspension cultures; Hairy root cultures and their cultivation. Techniques in raising transgencies.

Characteristics of animal cells:
Metabolism, regulation and nutritional requirements for mass cultivation of animal cell cultures; Kinetics of cell growth and product formation and effect of shear force; Product and substrate transport; Micro & macro-carrier culture; Hybridoma technology; Live stock improvement; Cloning in animals; Genetic engineering in animal cell culture; Animal cell preservation.

Immunology:
The origin of immunology; Inherent immunity; Humoral and cell mediated immunity; Primary and secondary lymphoid organ; Antigen; B and T cells and Macrophages; Major histocompatibility complex (MHC); Antigen processing and presentation; Synthesis of antibody and secretion; Molecular basis of antibody diversity; Polyclonal and monoclonal antibody; Complement; Antigen-antibody reaction; Regulation of immune response; Immune tolerance; Hyper sensitivity; Autoimmunity; Graft versus host reaction.

Recombinant DNA Technology:
Restriction and modification enzymes; Vectors: plasmid, bacteriophage and other viral vectors, cosmids, Ti plasmid, yeast artificial chromosome; cDNA and genomic DNA library; Gene isolation; Gene cloning; Expression of cloned gene; Transposons and gene targeting; DNA labeling; DNA sequencing; Polymerase chain reactions; DNA fingerprinting; Southern and northern blotting; In-situ hybridization; RAPD; RFLP; Site-directed mutagenesis; Gene transfer technologies; Gene therapy.

Bioinformatics:
Major bioinformatics resources (NCBI, EBI, ExPASy); Sequence and structure databases; Sequence analysis (biomolecular sequence file formats, scoring matrices, sequence alignment, phylogeny); Genomics and Proteomics (Large scale genome sequencing strategies; Comparative genomics; Understanding DNA microarrays and protein arrays); Molecular modeling and simulations (basic concepts including concept of force fields).

Read more...

GATE Syllabus For Mechanical Engineering(ME)

GATE 2012 Syllabus For Mechanical Engineering

Engineering Mathematics
Linear Algebra:
Matrix algebra, Systems of linear equations, Eigen values and eigen vectors.

Calculus:
Functions of single variable, Limit, continuity and differentiability, Mean value theorems, Evaluation of definite and improper integrals, Partial derivatives, Total derivative, Maxima and minima, Gradient, Divergence and Curl, Vector identities, Directional derivatives, Line, Surface and Volume integrals, Stokes, Gauss and Green's theorems.

Differential equations:
First order equations (linear and nonlinear), Higher order linear differential equations with constant coefficients, Cauchy's and Euler's equations, Initial and boundary value problems, Laplace transforms, Solutions of one dimensional heat and wave equations and Laplace equation.

Complex variables:
Analytic functions, Cauchy's integral theorem, Taylor and Laurent series.

Probability and Statistics:
Definitions of probability and sampling theorems, Conditional probability, Mean, median, mode and standard deviation, Random variables, Poisson, Normal and Binomial distributions.

Numerical Methods:
Numerical solutions of linear and non-linear algebraic equations Integration by trapezoidal and Simpson's rule, single and multi-step methods for differential equations.

Applied Mechanics and Design

Engineering Mechanics:
Free body diagrams and equilibrium; trusses and frames; virtual work; kinematics and dynamics of particles and of rigid bodies in plane motion, including impulse and momentum (linear and angular) and energy formulations; impact.

Strength of Materials:
Stress and strain, stress-strain relationship and elastic constants, Mohr's circle for plane stress and plane strain, thin cylinders; shear force and bending moment diagrams; bending and shear stresses; deflection of beams; torsion of circular shafts; Euler's theory of columns; strain energy methods; thermal stresses.

Theory of Machines:
Displacement, velocity and acceleration analysis of plane mechanisms; dynamic analysis of slider-crank mechanism; gear trains; flywheels.

Vibrations:
Free and forced vibration of single degree of freedom systems; effect of damping; vibration isolation; resonance, critical speeds of shafts.

Design:
Design for static and dynamic loading; failure theories; fatigue strength and the S-N diagram; principles of the design of machine elements such as bolted, riveted and welded joints, shafts, spur gears, rolling and sliding contact bearings, brakes and clutches.

Fluid Mechanics and Thermal Sciences

Fluid Mechanics:
Fluid properties; fluid statics, manometry, buoyancy; control-volume analysis of mass, momentum and energy; fluid acceleration; differential equations of continuity and momentum; Bernoulli's equation; viscous flow of incompressible fluids; boundary layer; elementary turbulent flow; flow through pipes, head losses in pipes, bends etc.

Heat-Transfer:
Modes of heat transfer; one dimensional heat conduction, resistance concept, electrical analogy, unsteady heat conduction, fins; dimensionless parameters in free and forced convective heat transfer, various correlations for heat transfer in flow over flat plates and through pipes; thermal boundary layer; effect of turbulence; radiative heat transfer, black and grey surfaces, shape factors, network analysis; heat exchanger performance, LMTD and NTU methods.

Thermodynamics:
Zeroth, First and Second laws of thermodynamics; thermodynamic system and processes; Carnot cycle. irreversibility and availability; behaviour of ideal and real gases, properties of pure substances, calculation of work and heat in ideal processes; analysis of thermodynamic cycles related to energy conversion.

Applications:
Power Engineering: Steam Tables, Rankine, Brayton cycles with regeneration and reheat. I.C. Engines: air-standard Otto, Diesel cycles. Refrigeration and air-conditioning: Vapour refrigeration cycle, heat pumps, gas refrigeration, Reverse Brayton cycle; moist air: psychrometric chart, basic psychrometric processes. Turbomachinery: Pelton-wheel, Francis and Kaplan turbines - impulse and reaction principles, velocity diagrams.

Manufacturing and Industrial Engineering
Engineering Materials
Structure and properties of engineering materials, heat treatment, stress-strain diagrams for engineering materials.

Metal Casting:
Design of patterns, moulds and cores; solidification and cooling; riser and gating design, design considerations.

Forming:
Plastic deformation and yield criteria; fundamentals of hot and cold working processes; load estimation for bulk (forging, rolling, extrusion, drawing) and sheet (shearing, deep drawing, bending) metal forming processes; principles of powder metallurgy.

Joining:
Physics of welding, brazing and soldering; adhesive bonding; design considerations in welding.

Machining and Machine Tool Operations:
Mechanics of machining, single and multi-point cutting tools, tool geometry and materials, tool life and wear; economics of machining; principles of non-traditional machining processes; principles of work holding, principles of design of jigs and fixtures

Metrology and Inspection:
Limits, fits and tolerances; linear and angular measurements; comparators; gauge design; interferometry; form and finish measurement; alignment and testing methods; tolerance analysis in manufacturing and assembly.

Computer Integrated Manufacturing:
Basic concepts of CAD/CAM and their integration tools.

Production Planning and Control:
Forecasting models, aggregate production planning, scheduling, materials requirement planning.

Inventory Control:
Deterministic and probabilistic models; safety stock inventory control systems.

Operations Research:
Linear programming, simplex and duplex method, transportation, assignment, network flow models, simple queuing models, PERT and CPM.

Read more...

GATE 2012 Electrical Engineering(EE) Syllabus

GATE Electrical Engineering Syllabus
Electrical Engineering

Linear Algebra:
Matrix Algebra, Systems of linear equations, Eigen values and eigen vectors.

Calculus:
Mean value theorems, Theorems of integral calculus, Evaluation of definite and improper integrals, Partial Derivatives, Maxima and minima, Multiple integrals, Fourier series. Vector identities, Directional derivatives, Line, Surface and Volume integrals, Stokes, Gauss and Green's theorems.

Differential equations:
First order equation (linear and nonlinear), Higher order linear differential equations with constant coefficients, Method of variation of parameters, Cauchy's and Euler's equations, Initial and boundary value problems, Partial Differential Equations and variable separable method.

Complex variables:
Analytic functions, Cauchy's integral theorem and integral formula, Taylor's and Laurent' series, Residue theorem, solution integrals.

Probability and Statistics:
Sampling theorems, Conditional probability, Mean, median, mode and standard deviation, Random variables, Discrete and continuous distributions, Poisson, Normal and Binomial distribution, Correlation and regression analysis.

Numerical Methods:
Solutions of non-linear algebraic equations, single and multi-step methods for differential equations.

Transform Theory:
Fourier transform, Laplace transform, Z-transform.

Electrical Engineering

Electric Circuits and Fields:
Network graph, KCL, KVL, node and mesh analysis, transient response of dc and ac networks; sinusoidal steady-state analysis, resonance, basic filter concepts; ideal current and voltage sources, Thevenin's, Norton's and Superposition and Maximum Power Transfer theorems, two-port networks, three phase circuits; Gauss Theorem, electric field and potential due to point, line, plane and spherical charge distributions; Ampere's and Biot-Savart's laws; inductance; dielectrics; capacitance.

Signals and Systems:
Representation of continuous and discrete-time signals; shifting and scaling operations; linear, time-invariant and causal systems; Fourier series representation of continuous periodic signals; sampling theorem; Fourier, Laplace and Z transforms.

Electrical Machines:
Single phase transformer - equivalent circuit, phasor diagram, tests, regulation and efficiency; three phase transformers - connections, parallel operation; auto-transformer; energy conversion principles; DC machines - types, windings, generator characteristics, armature reaction and commutation, starting and speed control of motors; three phase induction motors - principles, types, performance characteristics, starting and speed control; single phase induction motors; synchronous machines - performance, regulation and parallel operation of generators, motor starting, characteristics and applications; servo and stepper motors.

Power Systems:
Basic power generation concepts; transmission line models and performance; cable performance, insulation; corona and radio interference; distribution systems; per-unit quantities; bus impedance and admittance matrices; load flow; voltage control; power factor correction; economic operation; symmetrical components; fault analysis; principles of over-current, differential and distance protection; solid state relays and digital protection; circuit breakers; system stability concepts, swing curves and equal area criterion; HVDC transmission and FACTS concepts.

Control Systems:
Principles of feedback; transfer function; block diagrams; steady-state errors; Routh and Niquist techniques; Bode plots; root loci; lag, lead and lead-lag compensation; state space model; state transition matrix, controllability and observability.

Electrical and Electronic Measurements:
Bridges and potentiometers; PMMC, moving iron, dynamometer and induction type instruments; measurement of voltage, current, power, energy and power factor; instrument transformers; digital voltmeters and multimeters; phase, time and frequency measurement; Q-meters; oscilloscopes; potentiometric recorders; error analysis.

Analog and Digital Electronics:
Characteristics of diodes, BJT, FET; amplifiers - biasing, equivalent circuit and frequency response; oscillators and feedback amplifiers; operational amplifiers - characteristics and applications; simple active filters; VCOs and timers; combinational and sequential logic circuits; multiplexer; Schmitt trigger; multi-vibrators; sample and hold circuits; A/D and D/A converters; 8-bit microprocessor basics, architecture, programming and interfacing.

Power Electronics and Drives:
Semiconductor power diodes, transistors, thyristors, triacs, GTOs, MOSFETs and IGBTs - static characteristics and principles of operation; triggering circuits; phase control rectifiers; bridge converters - fully controlled and half controlled; principles of choppers and inverters; basis concepts of adjustable speed dc and ac drives.

Read more...

GATE Electronics and Communication Engineering (EC) Syllabus

GATE 2012 Syllabus For Electronics and Communication Engineering

Engineering Mathematics
Linear Algebra:
Matrix Algebra, Systems of linear equations, Eigen values and eigen vectors.

Calculus:
Mean value theorems, Theorems of integral calculus, Evaluation of definite and improper integrals, Partial Derivatives, Maxima and minima, Multiple integrals, Fourier series. Vector identities, Directional derivatives, Line, Surface and Volume integrals, Stokes, Gauss and Green's theorems.

Differential equations:
First order equation (linear and nonlinear), Higher order linear differential equations with constant coefficients, Method of variation of parameters, Cauchy's and Euler's equations, Initial and boundary value problems, Partial Differential Equations and variable separable method.

Complex variables:
Analytic functions, Cauchy's integral theorem and integral formula, Taylor's and Laurent' series, Residue theorem, solution integrals.

Probability and Statistics:
Sampling theorems, Conditional probability, Mean, median, mode and standard deviation, Random variables, Discrete and continuous distributions, Poisson, Normal and Binomial distribution, Correlation and regression analysis.

Numerical Methods:
Solutions of non-linear algebraic equations, single and multi-step methods for differential equations.

Transform Theory:
Fourier transform, Laplace transform, Z-transform.

Electronics and Communication Engineering

Networks:
Network graphs: matrices associated with graphs; incidence, fundamental cut set and fundamental circuit matrices. Solution methods: nodal and mesh analysis. Network theorems: superposition, Thevenin and Norton's maximum power transfer, Wye-Delta transformation. Steady state sinusoidal analysis using phasors. Linear constant coefficient differential equations; time domain analysis of simple RLC circuits, Solution of network equations using Laplace transform: frequency domain analysis of RLC circuits. 2-port network parameters: driving point and transfer functions. State equations for networks.

Electronic Devices:
Energy bands in silicon, intrinsic and extrinsic silicon. Carrier transport in silicon: diffusion current, drift current, mobility, and resistivity. Generation and recombination of carriers. p-n junction diode, Zener diode, tunnel diode, BJT, JFET, MOS capacitor, MOSFET, LED, p-I-n and avalanche photo diode, Basics of LASERs. Device technology: integrated circuits fabrication process, oxidation, diffusion, ion implantation, photolithography, n-tub, p-tub and twin-tub CMOS process.

Analog Circuits:
Small Signal Equivalent circuits of diodes, BJTs, MOSFETs and analog CMOS. Simple diode circuits, clipping, clamping, rectifier. Biasing and bias stability of transistor and FET amplifiers. Amplifiers: single-and multi-stage, differential and operational, feedback, and power. Frequency response of amplifiers. Simple op-amp circuits. Filters. Sinusoidal oscillators; criterion for oscillation; single-transistor and op-amp configurations. Function generators and wave-shaping circuits, 555 Timers. Power supplies.

Digital circuits:
Boolean algebra, minimization of Boolean functions; logic gates; digital IC families (DTL, TTL, ECL, MOS, CMOS). Combinatorial circuits: arithmetic circuits, code converters, multiplexers, decoders, PROMs and PLAs. Sequential circuits: latches and flip-flops, counters and shift-registers. Sample and hold circuits, ADCs, DACs. Semiconductor memories. Microprocessor(8085): architecture, programming, memory and I/O interfacing.

Signals and Systems:
Definitions and properties of Laplace transform, continuous-time and discrete-time Fourier series, continuous-time and discrete-time Fourier Transform, DFT and FFT, z-transform. Sampling theorem. Linear Time-Invariant (LTI) Systems: definitions and properties; causality, stability, impulse response, convolution, poles and zeros, parallel and cascade structure, frequency response, group delay, phase delay. Signal transmission through LTI systems.

Control Systems:
Basic control system components; block diagrammatic description, reduction of block diagrams. Open loop and closed loop (feedback) systems and stability analysis of these systems. Signal flow graphs and their use in determining transfer functions of systems; transient and steady state analysis of LTI control systems and frequency response. Tools and techniques for LTI control system analysis: root loci, Routh-Hurwitz criterion, Bode and Nyquist plots. Control system compensators: elements of lead and lag compensation, elements of Proportional-Integral-Derivative (PID) control. State variable representation and solution of state equation of LTI control systems.

Communications:
Random signals and noise: probability, random variables, probability density function, autocorrelation, power spectral density. Analog communication systems: amplitude and angle modulation and demodulation systems, spectral analysis of these operations, superheterodyne receivers; elements of hardware, realizations of analog communication systems; signal-to-noise ratio (SNR) calculations for amplitude modulation (AM) and frequency modulation (FM) for low noise conditions. Fundamentals of information theory and channel capacity theorem. Digital communication systems: pulse code modulation (PCM), differential pulse code modulation (DPCM), digital modulation schemes: amplitude, phase and frequency shift keying schemes (ASK, PSK, FSK), matched filter receivers, bandwidth consideration and probability of error calculations for these schemes. Basics of TDMA, FDMA and CDMA and GSM.

Electromagnetics:
Elements of vector calculus: divergence and curl; Gauss' and Stokes' theorems, Maxwell's equations: differential and integral forms. Wave equation, Poynting vector. Plane waves: propagation through various media; reflection and refraction; phase and group velocity; skin depth. Transmission lines: characteristic impedance; impedance transformation; Smith chart; impedance matching; S parameters, pulse excitation. Waveguides: modes in rectangular waveguides; boundary conditions; cut-off frequencies; dispersion relations. Basics of propagation in dielectric waveguide and optical fibers. Basics of Antennas: Dipole antennas; radiation pattern; antenna gain.

Read more...

GATE Computer Science and Information Technology Syllabus 2012

GATE 2012 Computer Sc. and Information Technology Syllabus


Engineering Mathematics

Mathematical Logic:
Propositional Logic; First Order Logic.

Probability:
Conditional Probability; Mean, Median, Mode and Standard Deviation; Random Variables; Distributions; uniform, normal, exponential, Poisson, Binomial.

Set Theory & Algebra:
Sets; Relations; Functions; Groups; Partial Orders; Lattice; Boolean Algebra.

Combinatorics:
Permutations; Combinations; Counting; Summation; generating functions; recurrence relations;asymptotics.

Graph Theory:
Connectivity; spanning trees; Cut vertices & edges; covering; matching; independent sets; Colouring; Planarity; Isomorphism.

Linear Algebra:
Algebra of matrices, determinants, systems of linear equations, Eigen values and Eigen vectors.

Numerical Methods:
LU decomposition for systems of linear equations; numerical solutions of non-linear algebraic equations by Secant, Bisection and Newton-Raphson Methods; Numerical integration by trapezoidal and Simpson's rules.

Calculus:
Limit, Continuity & differentiability, Mean value Theorems, Theorems of integral calculus, evaluation of definite & improper integrals, Partial derivatives, Total derivatives, maxima & minima.

Computer Science and Information Technology

Digital Logic:
Logic functions, Minimization, Design and synthesis of combinational and sequential circuits; Number representation and computer arithmetic (fixed and floating point).

Computer Organization and Architecture:
Machine instructions and addressing modes, ALU and data-path, CPU control design, Memory interface, I/O interface (Interrupt and DMA mode), Instruction pipelining, Cache and main memory, Secondary storage.

Programming and Data Structures:
Programming in C; Functions, Recursion, Parameter passing, Scope, Binding; Abstract data types, Arrays, Stacks, Queues, Linked Lists, Trees, Binary search trees, Binary heaps.

Algorithms:
Analysis, Asymptotic notation, Notions of space and time complexity, Worst and average case analysis; Design: Greedy approach, Dynamic programming, Divide-and-conquer; Tree and graph traversals, Connected components, Spanning trees, Shortest paths; Hashing, Sorting, Searching. Asymptotic analysis (best, worst, average cases) of time and space, upper and lower bounds, Basic concepts of complexity classes P, NP, NP-hard, NP-complete.

Theory of Computation:
Regular languages and finite automata, Context free languages and Push-down automata, Recursively enumerable sets and Turing machines, Undecidability.

Compiler Design:
Lexical analysis, Parsing, Syntax directed translation, Runtime environments, Intermediate and target code generation, Basics of code optimization.

Operating System:
Processes, Threads, Inter-process communication, Concurrency, Synchronization, Deadlock, CPU scheduling, Memory management and virtual memory, File systems, I/O systems, Protection and security.

Databases:
ER-model, Relational model (relational algebra, tuple calculus), Database design (integrity constraints, normal forms), Query languages (SQL), File structures (sequential files, indexing, B and B+ trees), Transactions and concurrency control.

Information Systems and Software Engineering:
information gathering, requirement and feasibility analysis, data flow diagrams, process specifications, input/output design, process life cycle, planning and managing the project, design, coding, testing, implementation, maintenance.

Computer Networks:
ISO/OSI stack, LAN technologies (Ethernet, Token ring), Flow and error control techniques, Routing algorithms, Congestion control, TCP/UDP and sockets, IP(v4), Application layer protocols (icmp, dns, smtp, pop, ftp, http); Basic concepts of hubs, switches, gateways, and routers. Network security basic concepts of public key and private key cryptography, digital signature, firewalls.

Web technologies:
HTML, XML, basic concepts of client-server computing.

Read more...