Test: Communication Systems - 2 - Electronics and Communication Engineering (ECE) MCQ

To relay outdoor remotely located live programs, TV transmitter use

If each short element of signal occupies 20 ms, the speed is

It is found that in a telephone system 60 subscribers initiate calls during a 30 minute interval and the total duration of all the calls is 100 minutes. The load is

E and H fields are perpendicular to each other.

Consider the following:

1. A TV receiver antenna should pick up the TV signal and develop maximum voltage from the available strength of signal
2. It should reject unwanted signals
3. It should not suffer from co-channel interference
4. It should have a very narrowband

If transmission bandwidth is doubled in FM, SNR is

Directivity means

If the oscillator output is modulated by audio frequencies upto 10 kHz, the frequency range occupied by the side bands will be

The power to the portable unit of a cordless telephone is provided by

In a AM wave the carrier and one of the side bands is suppressed. If m = 0.5, the percentage saving in power is

Computer communication networks have

Assertion (A): A balun is an RF impedance matching transformer.

Reason (R): Sometimes a booster amplifier is used with a TV set.

In an FM system, when the AF is 500 Hz and the AF voltage is 2.4 V, the deviation is 4.8 kHz. If the AF voltage is now increased to 7.2 V, the new deviation will be

Modulation is also called detection.

The maximum range of a transmitter depends on

Consider the following statements about Yagi Uda antenna

1. It is unidirectional
2. Its gain is about 7 dB
3. It is used at VLF
4. The optimum separation is 0.11

In a two stage cascade amplifier, each stage has a gain of 10 dB and noise figure of 10 dB. The overall noise factor is

Fields are said to be circularly polarised if their magnitudes are

In a CD player the speed of CD is

Three analog signals, having bandwidths 1200 Hz, 600 Hz, 600 Hz are sampled at their Nyquist rates, encoded with 12 bit words, and time division multiplexed. The bit rate for the multiplexed signal is

In the output of a DM speech encoder, the consecutive pulses are of opposite polarity during time interval t₁ < t < t₂. This indicates that during this interval

A fascimile reproduction has a specification of 200 lines per frame, progressive scanning and 5 frames per second. The time to scan one line is