Q101
Open questionThe line code that has zero dc component for pulse transmission of random binary data is
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Communication Systems
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Q102
Open questionAn amplitude modulated signal is given by:
S(t) = 10cos(2π × 106t) + 5cos(2π × 106t)cos(2π × 103t) + 2cos(2π × 106t)cos(4π × 103t)
The effective modulation index is:
S(t) = 10cos(2π × 106t) + 5cos(2π × 106t)cos(2π × 103t) + 2cos(2π × 106t)cos(4π × 103t)
The effective modulation index is:
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Q103
Open questionA PLL can be used to demodulate
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Q104
Open questionNoise voltage varies in a resistor as
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Q105
Open questionRatio between SNR and of a signal is as follows
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Q106
Open questionDetermine the bandwidth of the FM signal for 5kHz audio signal modulated by a carrier of 50 MHz causing a frequency deviation of 25 kHz?
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Q107
Open questionIn a super heterodyne receiver, if the intermediate frequency is 10.7 MHz and the carrier frequency is 89.6 MHz, the image frequency is:
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Q108
Open questionFM discriminator changes the FM signal into
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Q109
Open questionX(t) is a stationary process with the power spectral density Sx(f) > 0 for all f. The process is passed through a system shown below.
Let SY(f) be the power spectral density of Y(t). Which one of the following statements is correct?
Let SY(f) be the power spectral density of Y(t). Which one of the following statements is correct?
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Q110
Open questionAn AM broadcast station transmits modulating frequencies up to 6 kHz. If the AM station is transmitting on a frequency of 894 kHz, the values for maximum and minimum upper and lower sidebands and the total bandwidth occupied by the AM station are:
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Q111
Open questionThe FM techniques in telemetry is usually employed at:
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Q112
Open questionWhich type of demodulator used in FM detection
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Q113
Open questionAn amplitude modulated signal is (A + 0.5Acosωmt)cosωct where ωm and ωc are respectively, modulating and carrier frequencies. The power efficiency is
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Q114
Open questionIn radio receiver the output from local oscillator is fed to
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Q115
Open questionA superheterodyne receiver has an IF of 465 kHz. If it is tuned to a station broadcasting at 500 kHz and its oscillator is operating at 965 kHz, then the 1430 kHz frequency would be the
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Q116
Open questionWhich of the following is a result of over modulation?
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Q117
Open questionIf the covariance of two random variable X and Y is µXY, their correlation coefficient ρXY is:
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Q118
Open questionWhen a PLL is used as an FM demodulator, the demodulated signal appears at
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Q119
Open questionA uniformly distributed random signal x[n] with mean mx = 2 and variance = 3, is passed through a 3-point moving-average filter having an impulse response What will be the mean and variance of output?
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Q120
Open questionA 200-watt carrier is amplitude-modulated to a depth of 50%. What is the total power in the modulated wave?
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