Spectral Analysis – a Fourier transform tutorial – part #5

This part of the tutorial demonstrates the Fourier transform operation in a few cases of periodic and aperiodic signals, such as an AM signal, an FM signal, a rectangular nonrepetitive signal and a cardinal sinus signal. The last slide contains an application to the scaling property of the Fourier transform on a nonrepetitive time signal. It actually shows that spreading a signal in the time domain shrinks its spectrum and…

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How to Model a Phase-Locked Loop (PLL) in Excel – part#1

A Phase-Locked Loop is a type of electronic circuit. It generates an oscillation with the same frequency as a reference oscillation and a relatively constant phase difference  with respect to the same reference. The applications spectrum of such a circuit are extremely wide. Signal modulation, demodulation, detection and filtering, frequency conversion and synthesis are just a fraction of what this circuit can do. Though very simple, it is often not enough understood in industry by…

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Static Lissajous Emulators (2D and 3D)

This is a static Lissajous emulator in the sense that the waveform is obtained by combining 2 static sinusoidal waves with different frequencies. As a paranthesis, I will be preparing a dynamic version which will look just like the wave shape seen on a real oscilloscope. The file presented here has two different worksheets, the first one contains a classic 2D Lissajous figure and the second one has a 3D Lissajous pattern obtained from three different…

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