COMMUNICATION INTERVIEW QUESTIONS
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Important Topics
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Analog Modulation

Amplitude Modulation

Frequency Modulation

Modulation Index,Bandwidth....

Nyquist Criteria for communication

Channel Capacity Theorem

Pulse Code Modulation

Adaptive Pulse Code Modulation

Differential Pulse Code Modulation

Radar Types

Primary and Secondary Radars

MDI

Frequency ranges- HF,VHF,UHF,Microwave….

Digital Modulation Techniques

FSK, PSK, QPSK, MSK, Gaussian MSK


Sample Questions

1. A 2MB PCM (pulse code modulation) has…

a) 32 channels
b) 30 voice channels & 1 signaling channel.
c) 31 voice channels & 1 signaling channel.
d) 32 channels out of which 30 voice channels, 1 signaling channel, & 1 synchronization channel.

Ans: (c)

2. Time taken for 1 satellite hop in voice communication is…

a) 1/2 second
b) 1 seconds
c) 4 seconds
d) 2 seconds

Ans: (a)

3. Max number of satellite hops allowed in voice communication is:

a) only one
b) more han one
c) two hops
d) four hops

Ans: (c)

4. What is the maximal decimal number that can be accommodated in a byte?

a) 128
b) 256
c) 255
d) 512

Ans: (c)

5. Conditional results after execution of an instruction in a micro processor is stored in…

a) register
b) accumulator
c) flag register
d) flag register part of PSW(Program Status Word)

Ans: (d)

6. Frequency at which VOICE is sampled is…

a) 4 KHz
b) 8 KHz
c) 16 KHz
d) 64 KHz

Ans: (a)

7. Line of sight is…

a) Straight Line
b) Parabolic
c) Tx & Rx should be visible to each other
d) none of the above

Ans: (c)

8. Purpose of PC(Program Counter) in a MicroProcessor is…

a) To store address of TOS(Top Of Stack)
b) To store address of next instruction to be executed.
c) count the number of instructions.
d) to store base address of the stack.

Ans: (b)

9. What action is taken when the processor under execution is interrupted by a non-maskable interrupt?

a) Processor serves the interrupt request after completing the execution of the current instruction.
b) Processor serves the interrupt request after completing the current task.
c) Processor serves the interrupt request immediately.
d) Processor serving the interrupt request depends upon the priority of the current task under execution.

Ans: (a)

10. The status of the Kernel is…

a) task
b) process
c) not defined.
d) none of the above.

Ans: (b)

11. What is the nominal voltage required in subscriber loop connected to local exchange?

a) +48 volts
b) -48 volts
c) 230 volts
d) 110 volts

12. To send a data packet using datagram , connection will be established…

a) before data transmission.
b) connection is not established before data transmission.
c) no connection is required.
d) none of the above.

Ans: (c)

13. Word alignment is…

a) aligning the address to the next word boundary of the machine.
b) aligning to an even boundary.
c) aligning to a word boundary.
d) none of the above.

Ans: (a)

14. When a C function call is made, the order in which parameters passed to the function are pushed into the stack is…

a) left to right
b) right to left
c) bigger variables are moved first than the smaller variales.
d) smaller variables are moved first than the bigger ones.
e) none of the above.

Ans: (b)

15. What is the type of signaling used between two exchanges?

a) inband
b) common channel signaling
c) any of the above
d) none of the above.

Ans: (a)

16. Buffering is…

a) the process of temporarily storing the data to allow for small variation in device speeds
b) a method to reduce cross talks
c) storage of data within transmitting medium until the receiver is ready to receive.
d) a method to reduce routing overhead.

Ans: (a)

17. Memory allocation of variables declared in a program is…

a) allocated in RAM.
b) allocated in ROM.
c) allocated on stack.
d) assigned to registers.

Ans: (c)

18. A software that allows a personal computer to pretend as a computer terminal is …

a) terminal adapter
b) bulletin board
c) modem
d) terminal emulation

Ans: (d)