Am Demodulation Matlab

How To Articles

I have been working with MATLAB for quite some time now, and one of the most interesting topics I’ve come across is AM demodulation using MATLAB. In this article, I will go into detail about how to demodulate an amplitude modulated (AM) signal using MATLAB, and share some personal insights and commentary along the way. So let’s dive in!

The Basics of AM Demodulation

Before we get into the specifics of implementing AM demodulation in MATLAB, let’s first understand the basics of AM modulation and demodulation. AM modulation involves varying the amplitude of a carrier signal based on the intensity of the input signal (also known as the modulating signal). This modulated signal can then be transmitted over a medium, such as air or a wire.

AM demodulation, on the other hand, is the process of extracting the original modulating signal from the received AM signal. This is done by reversing the process of modulation, effectively recovering the original signal from the carrier wave.

Implementing AM Demodulation in MATLAB

MATLAB provides a powerful set of functions and tools for signal processing, making it an excellent choice for implementing AM demodulation algorithms. To get started, we need to have the AM signal that we want to demodulate.

Once we have the AM signal, we can use the MATLAB function hilbert to obtain the complex envelope of the signal. The complex envelope represents the original modulating signal, which is obtained by shifting the frequency spectrum of the AM signal to baseband.

Here’s a code snippet that demonstrates how to perform AM demodulation using the hilbert function in MATLAB:

% Load the AM signal
am_signal = load('am_signal.mat');

% Compute the complex envelope using hilbert transform
complex_envelope = hilbert(am_signal);

% Extract the original modulating signal
modulating_signal = real(complex_envelope);

% Plot the demodulated signal
title('Demodulated Signal');

In the above code, we first load the AM signal from a file (assuming it is stored as a MATLAB variable). Then, we use the hilbert function to compute the complex envelope of the AM signal. Finally, we extract the original modulating signal by taking the real part of the complex envelope. We can then visualize the demodulated signal using the plot function.

Personal Insights and Commentary

Implementing AM demodulation in MATLAB can be a fascinating exercise, as it allows us to gain a deeper understanding of how modulation and demodulation work in practice. It’s incredible to see how MATLAB simplifies the process by providing convenient functions like hilbert.

During my exploration of AM demodulation in MATLAB, I found that signal processing is a vast field with endless possibilities. MATLAB’s extensive signal processing toolbox opens up a world of opportunities for designing and implementing complex demodulation algorithms.

Moreover, by experimenting with different AM signals and exploring the effects of noise and interference, I was able to gain valuable insights into the robustness and limitations of AM demodulation techniques. This hands-on experience deepened my understanding of the underlying principles and helped me develop more effective demodulation algorithms.


AM demodulation using MATLAB is an exciting and educational topic that allows us to explore the world of signal processing. By understanding the basics of AM modulation and demodulation, and leveraging the powerful tools provided by MATLAB, we can effectively extract the original modulating signal from the received AM signal. Through personal exploration and experimentation, we can gain valuable insights and improve our demodulation algorithms. So why not give it a try and dive into the fascinating world of AM demodulation with MATLAB? Happy coding!