Communication Systems

An amplitude modulated wave is represented by the expression v_m = 5(1 + 0.6 cos 6280t) sin(211 × 10⁴ t) volts The minimum and maximum amplitudes of the amplitude modulated wave are, respectively

Given below are two statements : Statement I : A speech signal of 2 kHz is used to modulate a carrier signal of 1 MHz. The bandwidth requirement for the signal is 4 kHz. Statement II : The side band frequencies are 1002 kHz and 998 kHz. In the light of the above statements, choose the correct answer from the options given below :

If a message signal of frequency 'f_m' is amplitude modulated with a carrier signal of frequency 'f_c' and radiated through an antenna, the wavelength of the corresponding signal in air is :

A carrier signal C(t) = 25 sin(2.512 $$\times$$ 10¹⁰t) is amplitude modulated by a message signal m(t) = 5 sin(1.57 $$\times$$ 10⁸t) and transmitted through an antenna. What will be the bandwidth of the modulated signal?

In amplitude modulation, the message signal V_m(t) = 10 sin (2$$\pi$$ $$\times$$ 10⁵t) volts and Carrier signal V_C(t) = 20 sin(2$$\pi$$ $$\times$$ 10⁷ t) volts The modulated signal now contains the message signal with lower side band and upper side band frequency, therefore the bandwidth of modulated signal is $$\alpha$$ kHz. The value of $$\alpha$$ is :

Only 2% of the optical source frequency is the available channel bandwidth for an optical communicating system operating at 1000 nm. If an audio signal requires a bandwidth of 8 kHz, how many channels can be accommodated for transmission :

Amplitude modulated wave is represented by $${V_{AM}} = 10\,[1 + 0.4\cos (2\pi \times {10^4}t)]\cos (2\pi \times {10^7}t)$$. The total bandwidth of the amplitude modulated wave is :

Choose the correct statement for amplitude modulation :

A sinusoidal wave y(t) = 40sin(10 $$\times$$ 10⁶ $$\pi$$t) is amplitude modulated by another sinusoidal wave x(t) = 20sin (1000 $$\pi$$t). The amplitude of minimum frequency component of modulated signal is :

Match List I with List II .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-0lax{text-align:left;vertical-align:top} List - I List -II A. Facsimile I. Static Document Image B. Guided media Channel II. Local Broadcast Radio C. Frequency Modulation III. Rectangular wave D. Digital Signal IV. Optical Fiber Choose the correct answer from the following options: