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Speed and accuracy greatly improved!

A project log for Full Stack GPS Receiver

From raw RF samples of the GPS L1 C/A signal to a position fix, in a completely open fashion

Mike "Hamster" Field 05/03/2017 at 10:390 Comments

I thought up a away to improve the speed - now uses about 3% of a CPU core per channel. The speedup also allows the early/late tracking that is used to follow the Space Vehicle's Gold code to be change from +/- 1 .0 chip (1/1023th of a ms) to +/-0.75 chip.

This allows more accurate tracking, giving more accurate pseudoranges and more precise fixes. Adding an averaging filter removes quite a bit of the remaining noise too.

Now I am in the ballpark of a commercial GPS module!

Here is the console output as it runs, showing it as it tracks 7 channels:

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