##Reception of GPS signals from RTL-SDR and getting raw GPS data
- Using GNU radio software to realize the incoming data and plot its spectrum.
- GPS signals are well below the thermal noise, but can be received because it uses C/A signals which uses Spectrum spreading using PRN (Pseudo Random) Codes.
- By correlating the received signal (which looks like noise) by the C/A PRN code, GPS receivers receive data from satellites
##Results
- How PRN gold codes look like?, here are g5 and g17 C/A codes
- Results Yet, correlation of raw signal with all the 37 CA codes
- With self simulated data without noise, the power of correlation
####Check List!!!- check the CA code correlation on the simulated noise!
- Correlate Code spreaded data with the cacode, simulation
- construct time domain sinc filtered signal from gold codes with data representation similar to GPS signal
- resample the signal simulating Doppler effect due to satellite and predict Doppler shift from GPS signal buried under noise
##Following links were referenced :
- C/A Code Generator in python MATLAB
- Information about CDMA band allocation
- Hobbyiest Guide to RTL-SDR an interesting read
- Soft GPS Project Page
- 1 bit ADC and a short video description here
- 1 bit processing of BOC
- GNSS SDR, contains specs about RTL-SDR
- A homemade GPS Receiver
- [Satellite Signal Acquisition, Tracking, and Data Demodulation] (http://www.artechhouse.com/uploads/public/documents/chapters/kaplan_894_CH05.pdf)
- A homemade receiver for GPS & GLONASS satellites
- GPS simulated signal Generation