# Questions tagged [fourier]

Anything related to Fourier series, Fourier transform and similar mathematical tools used to analyze the frequency content of a signal.

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### LCR circuits with changing input frequencies

simulate this circuit – Schematic created using CircuitLab Ok, imagine an LCR circuit with a resonant frequency f connected to a signal generator inputting a sine wave. The signal generator ...
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### Fourier Transform Impulse

My friend and I are revising and we are confused on how to start the question below, and we're hoping someone could give us a hint. Sorry if it's a bit blurry. We have the following equation, but ...
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### Understanding harmonics of different Amplifier Circuits (A,AB,AB w/OP-Amp)

I have been test the circuits for amplifiers and got somewhat stuck in understanding the results for the FFT's harmonics. With a standard type B I was able to get this graph for the harmonics for ...
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### Why is X(jw) real and even if x(t) is real and even

So I'm going through Oppenheim's (really excellent) textbook "Signals and Systems" (2nd ed.) and the associated MIT course and I'm having an issue with the properties of the Fourier transform. On page ...
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### Does the sign matter on the frequency response?

I've been trying to calculate the frequency response of a series LR circuit with the output measured across the resistor. I solved it in two ways, one by taking the Fourier Transform of the impulse ...
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### Fourier transform to understand filtering on PWM

Is it correct to analyse the impact of a low-pass by regarding at the Fourier transform of a PWM signal, even if this one is generated with a H-Bridge ? And deduce that the higher frequencies forming ...
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### Laplace domain: poles on both sides of the jw and x plane

For a pole/zero plot, if a system has a pole on the left side only it is stable, and if the pole is on the right only it is not stable, but if the pole is on the right and left, would that be stable? ...
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### Calculating real part of a square wave

i'm trying to understand how Bruno putzey in Globally Modulated Self-Oscillating Amplifier with Improved Linearity in section 4.2 Analysis comes to the equation in presented in (2), see snapshot below....
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