I'm wanting to recieve CDMA signals from satellite transmitters. I'd like to do it all in digital rather than analog. However my concern is obtaining corralation to despread an individual signal with the doppler effect from the satellite movement. I'd rather not perform the doppler search on the analog IF but if there is a way to perform this in the DSP that would be ideal. Now I've read how radar systems use "quarter turn" data to find the doppler. I'm not certain that it will work on satellites though.
Basically as I've read, in radar systems the first FFT is used for corralation with the broadcast carrier. Then past several DFT samples are FFT again across the bins to find the doppler of the return signal. I'm not completely clear on the full implementation of this as the article had no description of how the second FFT data was used.
I'm not certain that process would work. However I thought instead could I adjust the sample rate fed into the FFT comapred to the sample size to adjust the frequency of the corralation search instead?
If anyone has experience with this concept or has links to good information I can read I would greatly appreciate it.
Basically as I've read, in radar systems the first FFT is used for corralation with the broadcast carrier. Then past several DFT samples are FFT again across the bins to find the doppler of the return signal. I'm not completely clear on the full implementation of this as the article had no description of how the second FFT data was used.
I'm not certain that process would work. However I thought instead could I adjust the sample rate fed into the FFT comapred to the sample size to adjust the frequency of the corralation search instead?
If anyone has experience with this concept or has links to good information I can read I would greatly appreciate it.