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[wgbh66]

Hello everybody... my name is diana.... I am new in DSP.... and I am trying to learn it with matlab tools. can anyone tell me the best way to start?
I tried to have a look to sptool, but i think it is not enough to control the signal and analize it. my signals will be bioacoustics.
another silly questions:
1. i think we use filter to eliminate the noise, right?
2. what is the source of the noise? because if i have a signal, so it is my input, how can i say there is noise in it or not?! I thought that the noise is because of quantization of the amplitudes, so we loss information, which generates noise... is it true?
3. if i know the amplitudes vector of the signal, with its FS, what are the steps to analize it?
I appreciate your kindly reply.. I know that replies will help a lot of beginners like me. thank you