List of top Physics Questions on communication systems

Match List I with List II: 

List I		List II
A.	Attenuation	I.	Combination of a receiver and transmitter
B.	Transducer	II.	Process of retrieval of information from the carrier wave at received
C.	Demodulation	III.	Converts one form of energy into another
D.	Repeater	IV.	Loss of strength of a signal while propagating through a medium

Choose the correct answer from the options given below :

A modulating signal is a square wave, as shown in the figure If the carrier wave is given as $c ( t )=2 \sin (8 \pi t)$ volts, the modulation index is:

Match List I with List I:

List I		List II
A	AM Broadcast	I	88-108 MHz
B	FM Broadcast	II	540-1600 kHz
C	Television	III	3.7-4.2 GHz
D	Satellite Communication	IV	54 MHz​-890 MHz

 
Choose the correct answer from the options given below:

The height of the antenna is 98 m. The radius of Earth is 6400 km. The area up to which it will transmit signal is:

If the height of the tower used for LOS communication is increased by 21%, the percentage change in range is?

Which of the following frequencies does not belong to FM broadcast?

The required height of a TV tower which can cover the population of $603$ lakh is $h$ If the average population density is $100$ per square $km$ and the radius of earth is $6400\, km$, then the value of $h$ will be ______$m$

A sinusoidal carrier voltage is amplitude modulated The resultant amplitude modulated wave has maximum and minimum amplitude of $120 \, V$ and $80\, V$ respectively The amplitude of each sideband is :

In AM modulation, a signal is modulated on a carrier wave such that maximum and minimum amplitude are found to be $6 V$ and $2 V$ respectively The modulation index is

Height of the receiving and transmitting antenna in communication of a signal are 245 m and 180 m respectively. Find the maximum distance between the two antennas for proper communication.

If the height of the tower used for L.D.S is increased by 21% then percentage change in range is?

In satellite communication, the uplink frequency band used is :

By what percentage will the transmission range of a TV tower be affected when the height of the tower is increased by 21% ?

Line-of-sight communication happens by means of :

At a particular station, the TV transmission tower has a height of 100 m. To triple its coverage range, height of the tower should be increased to

The height of a transmitting antenna at the top of a tower is 25 m and that of receiving antenna is, 49 m. The maximum distance between them, for satisfactory communication in LOS (Line-Of-Sight) is \(K\sqrt5\times10^2\ m\). The value of K is ______ .
(Assume radius of Earth is \(64×10^5\ m\))
[Calculate upto nearest integer value]

A FM Broad cast transmitter, using modulating signal of frequency 20 kHz has a deviation ratio of 10. The Bandwidth required for transmission is

In communication systems, the device used to convert energy from one form to another form is

For a generalised communication system, arrange the following in the correct sequence:
(A) Receiver
(B) Information source
(C) channel
(D) User of information
(E) Transmitter

In the case of amplitude modulation to avoid distortion the modulation index $(\mu)$ should be:

A radio can tune to any station in $6\, MHz$ to $10\, MHz$ band The value of corresponding wavelength bandwidth will be :

An amplitude modulated wave is represented by the expression $v _{ m }=5(1+0.6 \cos 6280 t )$ $\sin \left(211 \times 10^{4} t \right)$ volts. The minimum and maximum amplitudes of the amplitude modulated wave are, respectively :

An amplitude modulated signal is plotted below:

Which one of the following best describes the above signal ?

An amplitude modulated signal is given by $V(t) = 10[1 + 0.3 \cos(2.2 \times 10^4)] \sin(5.5 \times 10^5t)$. Here t is in seconds. The sideband frequencies (in kHz) are, [Given $\pi = 22/7$]