frequency and phase modulation

In this type of modulation, E c , w c are kept constant. The phase angle q of the carrier wave is varied according to the modulating wave. The common name for "phase modulation" and "frequency modulation" is "angle mod..

Frequency Modulation - In frequency modulation, the frequency of the carrier wave is modified in accordance with the amplitude of the modulating wave. The amplitude of the carrier remains unchanged at all times. In other words, the amplitu..

In this type of modulation, E c and q are kept constant. The frequency w c of the carrier wave is varied in accordance with the modulating wav..

(i) Various electrical machines and noises cause amplitude disturbance in the transmission of amplitude-modulated wave. This makes the reception noisy. So, there is a need for different type of modulation, which can reduce the noise factor. Frequency modulation..

Different Types of Modulation - Consider a carrier wave represented by Here e c is instantaneous value, E c is amplitude (maximum value), w c is angular frequency and q is the phase angle of carrier voltage. Corresponding to the three variables E c , w c and q, we can ..

Principles of Light Modulation - Let us consider the case of electromagnetic radiation in an ionised medium. Suppose we increase/decrease the amplitude of an electromagnetic wave passing through an ionised gas. These modulations of the electromagnetic wave could contain coded in..

In amplitude modulation and frequency modulation, the modulation was done by sinusoidal signals. In pulse modulation, short pulses may do the modulation of a radio-frequency carrier. The simplest of these is the conventional tele..

In amplitude modulation and frequency modulation, the modulation was done by sinusoidal signals. In pulse modulation, short pulses may do the modulation of a radio-frequency carrier. The simplest of these is the conventiona..

Amplitude Modulation - When the amplitude of high frequency carrier wave is changed in accordance with the intensity of the signal, it is called amplitude modulation. In amplitude modulation, only the amplitude of the carrier wave is changed in accordance wit..

The amplitude-modulated band (AM band) contains the radio waves having frequency of less than 30 MHz or having wavelength of 10 m or more. The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emit..