Quadrature ( I-Q ) Modulation Tutorial

Learn quadrature modulation through interactive flash programs

 

HINT: If program is too big for screen click mouse in program then push "CTRL" and spin mouse wheel at the same time... or push F11 for full screen.

This Quadrature Modulation Tutorial Consists of 4 Flash programs with embedded audio. These programs will allow you to learn about quadrature modulation and quadrature demodulation without getting overwhelmed by math.

Flash Program Description

I Q Modulation
Programs

Tutorial 1

Shows I-Q Modulation to change the phase of a signal, to change the frequency of a signal and to change the amplitude of a signal. This is the basis for AM, FM and Phase modulation when using quadrature ( I- Q ) modulation techniques.

Click here

pic1

(approx 4M of Audio)

Tutorial 2

This program shows how Quadrature data is put into an FFT as complex data (i e as I+jQ). This program reveals how a complex FFT allows for more information than a real ony data stream. This program reveals how when I Q data is used that not only is the frequency of detected video known, but also whether the demodulated frequency came from the positive or negative side of the carrier.

Click here

pic2

(approx 2 M of Audio)

Tutorial 3

This program allows the user to adjust the incoming signals frequency and phase relative to the sampling frequency and to see the I Q data stream that results. It also shows the beginner how to interpret the I Q data stream.

Click here

pic3

(approx 2 M of Audio)

Tutorial 4

This program shows how an IQ data stream is used to demodulate an Amplitude modulated signal.

Click Here

pic4

(approx 3 M of Audio)