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Unread 10-12-2009, 01:32
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Re: finding amplitude of a specific frequency

Well, I guess I should follow up on this.
For now I'm using a modified "Extract single tone information.vi" to look at the amplitudes of multiple frequencies using a single Fourrier transform. (apparently the FFT gives me a Hann spectrum; I'm probably not going to take the time to determine why that specific windowing function is used over others)

I was unable to find any Discrete Fourrier Transform functions - they seem to be only available in Mathscript. We do not get Mathscript with the FRC version of LabVIEW.

Phase Lock Loops are an excellent method on a hardware level, because of the ease of signal generation and comparison. However, on the software level, it seems very inefficient to be continuously subtracting and integrating a waveform.


You may be wondering why I'd care to do it in software:
I'm planning a simple communication protocol between robots, and I'd like to chose the frequencies for their transmission and noise characteristics, not be limited to frequencies that are commonly used (and run the risk of excessive sound output to ensure the message can be recieved).
Also, software is easier to distribute than hardware.
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