I need to implement an ASK (ampliltude shift keying) demodulation using a DSP ( a dsPIC ) and programming in C. Especifically talking, I need to demodulate a signal from a car's key transponder. I already have a circuit of antenna that receive the signal and I already can sample it, but I still have a doubt of how could be the best way, faster and reliable, to filter the signal. I was using a FIR filter using Kaiser windowing and 13 taps, but it demanded a lot of processing time and I still have some errors. Is there a better way to do it ?
With my best regards, Daniel.