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AM demodulation

Started by Steve October 7, 2003
> ... AM demodulation algorithm ...
Do a google search on "satellite_seminar.pdf." There will be two sites that come up. Click on the princeton site which will download the pdf document. Look on page 16 of that pdf document for an AM demodulation algorithm. Look on page 17 for a JAVA implementation. This algorithm works fine, because I have used it; however, you must consider 1) the input audio signal format to be demodulated and 2) the sample rate that you demodulate. Otherwise, your picture will look like random garbage. To briefly explain ... 1) I used an 8 bit WAV file to record the weather satellite audio signal, so I had to subtract 127 from the WAV data before I applied the AM demodulation algorithm. 2) each line has a visible image and an IR image. You must consider your sample rate because you will want to toss some data; otherwise, your image will be slanted. After you get this working, you will probably want to use wxsat. By the way, you really should try to understand the math! Ken