What is PAM & PWM?

What is PAM & PWM?

Pulse modulation is divided into two types as analog and digital modulation. The analog pulse modulation techniques are further classified into Pulse Amplitude Modulation (PAM), Pulse Width Modulation (PWM) and Pulse Position Modulation (PPM).

What is PPM vs PWM?

PWM stands for Pulse Width Modulation and PPM stands for Pulse Position Modulation. PWM is a technique used to relay data in the form of a varying pulse width. In PPM (Pulse Position Modulation) the analogue sample values determine the position of a narrow pulse relative to the clocking time.

What is the main advantage of PPM over PAM and PWM?

Advantages of Pulse Position Modulation (PPM): Pulse position modulation has low noise interference when compared to PAM because amplitude and width of the pulses are made constant during modulation. Noise removal and separation is very easy in pulse position modulation.

What is PWM in digital communication?

Pulse width modulation (PWM) is a powerful technique for controlling analog circuits with a microprocessor’s digital outputs. PWM is employed in a wide variety of applications, ranging from measurement and communications to power control and conversion.

Which is better PAM PWM PPM?

Key Differences Between PAM, PWM and PPM Whereas in PPM the position of the pulses is proportional to the amplitude of analog modulating signal. PAM technique shows low immunity towards the noise. As against PWM and PPM has low noise interference factor because their noise immunity is high.

What is PPM PAM PWM?

PAM-PWM-PPM. PAM stands for Pulse Amplitude Modulation PWM stands for Pulse Width Modulation PPM stands for Pulse Position Modulation. In an PAM system the message signal is usually flat top sampled with the carrier signal. In PWM with the change in the amplitude of message signal, the width of the pulses varies.

Why is PAM not used for communication applications?

PAM is essentially AM, but quantized in both time and amplitude. The most prominent disadvantage of PAM is that most transmission mediums exhibit some ‘loss’, and so the received pulse stream will be distorted in terms of amplitude — which means, in turn, that the received information may be distorted as well!

What is the bandwidth of PAM?

Now, if the ‘ON’ and ‘OFF’ time of the pulse amplitude modulated (PAM) pulse is same then maximum frequency of the PAM pulse will be equal to, Therefore, the bandwidth required for the transmission of a PAM signal would be equal to the maximum frequency fmax given by the above equation.

What are the advantages and disadvantages of PAM PWM and PPM?

➨It is easy to separate out signal from noisy signal. ➨It has highest power efficiency among all three types. ➨Instantaneous power of PPM modulated signal remains constant due to constant pulse widths and pulse amplitudes. ➨It requires less power compare to PAM due to short duration pulses.

What is the difference between PWM and PAM?

In PAM, the amplitude of the pulsed carrier signal is varied according to the amplitude of analog modulating signal. In PWM, the width of the pulses of the carrier wave is varied according to the modulating signal. As against, in PPM, the position of the pulses shows variation according to the modulating signal.

What is PAM in communication?

Pulse-amplitude modulation (PAM), is a form of signal modulation where the message information is encoded in the amplitude of a series of signal pulses.

What is the main advantage of PPM over PAM?

Benefits or advantages of PPM ➨It has highest power efficiency among all three types. ➨Instantaneous power of PPM modulated signal remains constant due to constant pulse widths and pulse amplitudes. ➨It requires less power compare to PAM due to short duration pulses.

What is the difference between PWM and Pam?

PWM is an acronym used for pulse width modulation. In PWM the width of the pulses is varied according to the amplitude of the message signal. The figure below shows the pulse width modulated signal: As we can see that unlike PAM, in this technique the amplitude of the signal is constant and only the width is varying.

How are pulse width modulated in PWM and PPM?

Each trailing of the pulse width modulated signal becomes the starting point for pulses in the PPM signal. Hence, the position of these pulses is proportional to the width of the PWM pulses. But the main disadvantage of the PPM modulation technique is, The synchronization between transmitter and receiver must be needed.

Which is a disadvantage of ppm over PWM?

Hence, the position of these pulses is proportional to the width of the PWM pulses. But the main disadvantage of the PPM modulation technique is, The synchronization between transmitter and receiver must be needed. In all the above cases, we detect the message of the pulse modulated signal and reconstruct the original analog signal.

Which is better Pam or PPM modulated signal?

➨Instantaneous power of PPM modulated signal remains constant due to constant pulse widths and pulse amplitudes. ➨It requires less power compare to PAM due to short duration pulses. ➨System is highest in complexity to implement. ➨It requires very large bandwidth (BW) compare to PAM.