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Finding an raw data source for initial experments

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 04/06/2017 at 02:580 Comments

It is very hard to find raw RF data for analysis. The only source I was able to find on the internet was http://www.jks.com/gps/gps.html

It contains a 59 MB file, that has the following properties:

It is important to note that the intermediate frequency is above half the sample rate - this will cause signals to be aliased down to 4.092 - (5.456/2) = 1.364 MHz, and the spectrum to be inverted.

If you download this file, and combine it with the project's C source, you will be able to experiment with this project and obtain a valid position fix. To do this, use the following command line

fsgps -s 5456000 -i 4092000  gps.samples.1bit.I.fs5456.if4092.bin

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