Company: Airports Authority of India (AAI)
AAI written Test consists 2 sections
Non-Technical (GK,Verbal Ablity,Reasoning,Quantitiative)
Time Limit-2 hours
AAI written test Technical Questions
1. Which of the following schemes have the best error performance with the same energy per bit?
1. 16QAM b. 16PSK c. QPSK
2. Same Antenna is used for Tx and Rx. Radar range related to Antenna gain as
1. Directly prop. To G
2. Direc. Prop. To sq. root of G
3. Inversely prop to G
3. Thermal Noise in conductor related to B
4. Square root of B
4. A control system with feed back gain 0.1 and forward gain 10. What is the sensitivity of the system w.r.t the feed back system.
5. The value of ‘k’ for the system to be stable is. ( 6th degree Characteristic Eqn given)
6. Which of the following system is stable.
1. As2 + Bs +C
2. As2 – Bs +C
3. As4 + B s3 +Cs+D
4. -As2 – Bs -C
7. Linux OS based on which architecture
8. Comparison betweeb Macro and Subroutine
1. Macro better that Sub Rtne with respect to storage time and execution time
2. Vice versa
3. Macro better that Sub Rtne with respect to execution time only
4. Vice versa
9. Which of the following is a privileged instruction?
1. MOV A B
2. INT 21
3. ADD A B
4. IN 08
10. Which of the following instruction is not converted to binary by an Assebly Language Program ?
3. Privilige instruction
4. Sorry don’t remember
11. In which type of machine can multiple tasks be done
1. Virtual Machine
2. Sorry don’t remember
12. Which of the following has the highest distortion?
13. Which of the following distortions occur in Class B push pull amplifier?
4. Sorry don’t remember
14. ?(s)/T(s) of a rotational system (J,B,k regular notaions)
15. Schmitt Trigger with 3V & 1V UTP and LTP respectively. A sinusoidal input with 10V peak is fed as the input. The output swings between
16. Op-amp circuit given. Identify the circuit (Ans: Peak detector)
17. 6 bit binary ladder with 101001 as input ( 0= 0V , 1 = 10V). Output voltage is ——
18. Doppler Radar of 1125 MHz. Frequency of received echo is 125 MHz. The conclusion is
1. Target also has a radar
2. Target moving away
3. Target approaching
19. Microprocessor cycles between
1. Fetch and Execution operations.
2. Fetch and Halt
20. Modulation index of an FM system with 2.5V, 500 Hz input and 5KHz deviation is
21. Routh’s Criterion gives
1. Number of roots on the LHS of S plane
2. Number of roots on the RHS of S plane
22. For the system to be stable, the roots of the characteristic Equation must lie
1. Left side of the S plane
2. Right side of s plane
23. Impulse response h(t) of a system is
1. Inverse Laplace transform of Transfer Function
24. The output of a LTI system with Guassian process input is
25. Spectral Density and Auto-Correlation are
1. Laplace Transform pair
2. Fourier Transform Pair.
26. A flex Klystron is a
27. Oscillator(1MHz) à Divider (/ 10^6) à Schmitt Trigger à Flip Flop à. Output is
1. Pulse Train of width 1 sec
2. Pulse Train of width 2 sec
3. Pulse Train of width 0.5 sec
1. In a communication system, noise is most likely to affect the signal
(a) at the destination
(b) In the channel
(c) in the information source
(d) at the transmitter
2. Indicate the false statement. Fourier analysis shows that the saw tooth
wave consist of
(a) fundamental and subharmonic sine waves
(b) a fundamental sine wave and an infinite number of harmonics
(c) fundamental and harmonic sine waves whose amplitude decreases with
the harmonic number
(d) sinusoidal voltages, some of which are small enough to ignore in
3. One of the following types of noise becomes a great importance at high
frequencies. Is the
(a) random noise
(b) shot noise
(c) impulse noise
(d) transit-time noise
4.Indicate the false statement. The square of the thermal noise voltage generated by a resistor is proportional to
(a) its temperature
(b) Its resistance
(c) Boltzmann’s Constant
(d) the bandwidth over which it is measured
5.If the plate supply voltage for a plate modulated class C amplifier is V, the maximum plate-cathode voltage could be almost as high as
6. Which one will be stable if characteristics equation is
7.When microwave follows curvature of the earth, this I know as
(c) troposphere scatter
(d) ionosphere reflection
8. Broadband long distance communications are originally made possible by
the advent of
(a) telegraph cables
(b) repeater amplifiers
(c) HF radio
(d) Geostationary satellites
9. Switching systems
(a) Improve the efficiency of data transfer
(b) are not used in data system
(c) require additional lines
(d) are limited to small data networks
10. Basic group B
(a) occupies the frequency range from 60 to 108 k hz
(b) consist of erect channels only
(c) is formed at the group translating equipment
(d) consist of five super group
11. In differential amplifiers, the common emitter current is made constant
(a) To make Ad (differential gain) very small
(b) To make Ac (common mode gain) very small
(c) To make the amplifier symmetrical
(d) To keep CMRR constant
12. Given BCD number 1001 0011, its decimal equivalent is
13. An amplifier has voltage gain of 50. this gain in db will be
(a) 17 db
(b) 31 db
(c) 34 db
(d) 68 db
14. In a E plane Tee, the output of the two rams are
(a) 180 degree out of phase
(b) In the same phase
(c) 90 degree out of phase
(d) none of these
15. waveguide are generally made of
(c) Both (a) and (b)
(d) none of these
1.(b) 2.(a) 3.(d) 4.(a) 5.(a) 6.(a) 7.(b) 8.(b) 9.(a) 10.(a) 11.(b) 12.(c) 13.(c) 14.(a) 15.(c)
1.Radar is used for?
2.COHO in MTI Radar uses which freq.?
3.CMRR of amplifier?
4.Binary to hexadecimal conversion?
5. Decimal to hexadecimal conversion?
6.Firewalls are used for?
7.Full form of FPGA?
8.Numerical based on Duty cycle and peak power?
9.IF transmitted power is increased by 16 than range is increased by a) 16, b)8, c)4, d) none of these?
10.AGC is used in which of the stage a) receiver b) oscillator c) both a and b d) none of these?
11.Delayed AGC is used for which purpose?
12.Question based on the value of mirroring?
13.Question based on RAID.
14.Bridge is used for which of the OSI layer?
15. 5-6 questions are based on various OSI layer and TCP/IP.
16.Which type of feedback is used in amplifier a) +ve b) -ve c) both a and b d) none of these?
17.question based on i/p impedance of transmission line of a given wavelength.
18.What is three things for workstations of DNS server?
19.Which of the followinf is free-running?a)monostable multivibrator ,b)astable multivibrator, c)both a and b, d) none of these?
20. 2-3 questions based on voltage and current source.
21. One question of VCO.