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This set of Digital Communication Multiple Choice Questions & Answers (MCQs) focuses on Digital Communication Set 3
Q1 | The time interval over which the received signal may be sampledwithout error may be explained by
- width of eye opening of eye pattern
- rate of closure of eye of eye pattern
- height of the eye opening of eye pattern
- all of the above
Q2 | For a noise to be white Gaussian noise, the optimum filter is known as
- low pass filter
- base band filter
- matched filter
- bessel filter
Q3 | Matched filters are used
- for maximizing signal to noise ratio
- for signal detection
- in radar
- all of the above
Q4 | The number of bits of data transmitted per second is called
- data signaling rate
- modulation rate
- coding
- none of the above
Q5 | Pulse shaping is done
- to control inter symbol interference
- by limiting the bandwidth of transmission
- after line coding and modulation of signal
- all of the above
Q6 | The criterion used for pulse shaping to avoid ISI is
- nyquist criterion
- quantization
- sample and hold
- pll
Q7 | The filter used for pulse shaping is
- raised – cosine filter
- sinc shaped filter
- gaussian filter
- all of the above
Q8 | Roll – off factor is defined as
- the bandwidth occupied beyond the nyquist bandwidth of the filter
- the performance of the filter or device
- aliasing effect
- none of the above
Q9 | Nyquist criterion helps in
- transmitting the signal without isi
- reduction in transmission bandwidth
- increase in transmission bandwidth
- both a and b
Q10 | The Nyquist theorem is
- relates the conditions in time domain and frequency domain
- helps in quantization
- limits the bandwidth requirement
- both a and c
Q11 | The difficulty in achieving the Nyquist criterion for system design is
- there are abrupt transitions obtained at edges of the bands
- bandwidth criterion is not easily achieved
- filters are not available
- none of the above
Q12 | Equalization in digital communication
- reduces inter symbol interference
- removes distortion caused due to channel
- is done using linear filters
- all of the above
Q13 | Zero forced equalizers are used for
- reducing isi to zero
- sampling
- quantization
- none of the abov
Q14 | The transmission bandwidth of the raised cosine spectrum is given by
- bt = 2w(1 + α)
- bt = w(1 + α)
- bt = 2w(1 + 2α)
- bt = 2w(2 + α)
Q15 | The preferred orthogonalization process for its numerical stability is
- gram- schmidt process
- house holder transformation
- optimization
- all of the above
Q16 | For two vectors to be orthonormal, the vectors are also said to beorthogonal. The reverse of the same
- is true
- is not true
- is not predictable
- none of the above
Q17 | Orthonormal set is a set of all vectors that are
- mutually orthonormal and are of unit length
- mutually orthonormal and of null length
- both a & b
- none of the above
Q18 | In On-Off keying, the carrier signal is transmitted with signal value‘1’ and ‘0’ indicates
- no carrier
- half the carrier amplitude
- amplitude of modulating signal
- none of the above
Q19 | ASK modulated signal has the bandwidth
- same as the bandwidth of baseband signal
- half the bandwidth of baseband signal
- double the bandwidth of baseband signal
- none of the above
Q20 | Coherent detection of binary ASK signal requires
- phase synchronization
- timing synchronization
- amplitude synchronization
- both a and b
Q21 | The probability of error of DPSK is ______________ than that ofBPSK.
- higher
- lower
- same
- not predictable
Q22 | In Binary Phase Shift Keying system, the binary symbols 1 and 0 arerepresented by carrier with phase shift of
- Π/2
- Π
- 2Π
Q23 | BPSK system modulates at the rate of
- 1 bit/ symbol
- 2 bit/ symbol
- 4 bit/ symbol
- none of the above
Q24 | The BPSK signal has +V volts and -V volts respectively to represent
- 1 and 0 logic levels
- 11 and 00 logic levels
- 10 and 01 logic levels
- 00 and 11 logic levels
Q25 | The binary waveform used to generate BPSK signal is encoded in
- bipolar nrz format
- manchester coding
- differential coding
- none of the above