In amplitude modulation: A. Amplitude of carrier is varied by modulating signal B. Modulation index is between 0 and 1 C. Bandwidth is infinite D. Bandwidth is twice of minimum modulating frequency. Choose the correct answer from the options given below:
A and B only
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. In amplitude modulation, the information signal's specific characteristics vary the amplitude of the high-frequency carrier wave. Let's analyze each option to find the correct answer:
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A. Amplitude of carrier is varied by modulating signal:
In amplitude modulation, the amplitude or strength of the carrier wave is varied in accordance with the amplitude of the input signal. This means the amplitude of the carrier wave is directly affected by the modulating signal, which is true. Thus, option A is correct.
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B. Modulation index is between 0 and 1:
The modulation index is a measure of the extent of modulation in amplitude modulation. It is calculated as the ratio of the amplitude of the modulating signal to the amplitude of the carrier signal. For effective modulation without distortion, the modulation index is generally kept between 0 and 1. Therefore, this statement is true, making option B correct.
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C. Bandwidth is infinite:
The bandwidth in amplitude modulation is not infinite. It is, in fact, determined by the frequency of the modulating signal. The bandwidth is twice the frequency of the highest modulating signal component, not infinite. Therefore, this statement is incorrect.
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D. Bandwidth is twice of minimum modulating frequency:
The correct measure of bandwidth in amplitude modulation is twice the frequency of the highest frequency component of the modulating signal, not the minimum. Hence, this statement is incorrect.
Based on the analysis above, the correct answer is A and B only, as both statements are true for amplitude modulation.
Similar Questions
Assertion (A) : In amplitude modulation technique the modulation index should be close to 1.
Reason (R) : The power carried by message signal in the side bands increases with increase in modulation index.
Read the statements :
i. DSB has two side bands and SSB has one
ii. DSB has carrier and two side bands and SSB has a carrier and a side band
iii. DSB has carrier and two side bands and SSB without carrier and two different side bands.Which statements are correct ?
Assertion (A) : Amplitude modulation is wastage of power.
Reason (R) : Amplitude modulation is wastage of bandwidth.
The peak carrier voltage is 150 V. If the resistor is 200 Ω and the modulation index is 0.5, the total power in the AM signal is :
The modulation index of an AM wave is given by :
Consider an AM (amplitude modulated) signal
\(s(t) = 20\left[1 + 0.9\cos 2\pi \times 10^4 t\right]\cos 2\pi \times 10^6 t\)
The power efficiency (η) in the AM signal is
Match List I with List II
LIST I LIST II A. Power of AM Wave I. \(P_c\left(\frac{m^{2}}{4}\right)\) B. Power of VSB II. \(\frac{m^{2}}{4}P_c+F\left(\frac{m^{2}}{4}P_c\right)\) C. Power of SSB III. \(\frac{m^{2}}{4}\left(\frac{V_c^{2}}{2R}\right)+\frac{m^{2}}{4}\left(\frac{V_c^{2}}{2R}\right)\) D. Power of DSBSC IV. \(\frac{V_{carr}^{2}}{R}+\frac{V_{LSB}^{2}}{R}+\frac{V_{USB}^{2}}{R}\) Choose the correct answer from the options given below:
If 1 MHz carrier is amplitude modulated with a 5 kHz audio signal, the Upper Side Band (USB) and Lower Side Band (LSB) frequencies are ________ respectively.
Which of the following is associated with single balanced modulator circuit :
Important Questions from Amplitude Modulation
The highest modulation frequency typically used in AM broadcast is
Which of the following is NOT the advantage of amplitude modulation?
Bandwidth requirement for Amplitude modulated wave is:
The frequency range of AM radio is:
In an amplitude modulated system, a sinusoidal carrier signal of 1 MHz is modulated by a 10 kHz sinusoidal signal. If the lower sideband and the carrier are suppressed and if the amplitude modulated signal is sampled for further processing, what should be the minimum sampling frequency for baseband sampling?
