Q. Which of the following pulse modulation is analog?

View solution

Q. Pulse stuffing is used in

View solution

Q. In a modulator it is found that the amplitude spectrum consists a component at fc, the carrier frequency and one component each at fc - fs and fc + fs where fs is the modulating signal frequency. Then the modulator used is

View solution

Q. Frequency shift keying is used mostly in

View solution

Q. Troposphere is the portion of atmosphere

View solution

Q. Earth's curvature affects the effective height of antenna.

View solution

Q. In PCM, the quantization noise depends on

View solution

Q. How can the quantizing noise be reduced?

View solution

Q. Audio systems use transverse recording.

View solution

Q. In a CD player the laser uses

View solution

Q. Leak type bias is used in a plate-modulated class C amplifier to

View solution

Q. FM broadcast is done using

View solution

Q. In MTI radar, clutter means

View solution

Q. A sinusoidal carrier voltage, having frequency 1000 Hz is amplitude modulated by a sinusoidal voltage of frequency 15 kHz. The frequency of upper and lower sidebands will be

View solution

Q. Identical telephone numbers in different parts of a country are distinguished by their

View solution

Q. Consider the following statements as regards pulse repetition frequency

1. Pulse interval should be as large as possible so that a pulse returns before next pulse is transmitted
2. Greater the number of pulses reflected from a target, greater is the probability of distinguishing it from the noise

Which of the above are correct?

View solution

Q. Which gives minimum probability of error?

View solution

Q. If there are M messages and each message has probability p = 1/m, the entropy is

View solution

Q. Narrowband FM signal can be considered to be equal to

View solution

Q. The spectral component of noise associated with kth frequency is given, in the limit as Δf → 0 by nk(t) written as

nk(t) = Ck cos (2πk Δft + θk)

Consider the following statements as regards Ck and θk

1. Ck and θk are independent of one another
2. Ck and θk are independent of the amplitude of a spectral component at a different frequency
3. Ct and θk are independent of the phase of a spectral component at a different frequency

Which of the above statements are correct?

View solution