Incorrect pseudoranges can be a source of caluclation errors.
A type 2 PLL should be used.
Integrations/correlations inside the PLL should be done over 10-20ms.
This integration time will be dependent upon the maximum amount of gforce your application will experience.
For a stationary receiver integrations needed to be done faster than 1 second.
For an object traveling at 1 g force integration time needs to done faster than 19 ms.
This is to track within 1Hz of the carrier frequency.
A least mean squares curve fitting should be done on the calculated locations of data.
Here is a plot of the current jumps in C/A Code length for integrations over 1ms, along with carrier frequency.
C/A code length is adjusted based off a remainder from the last code length.
Thus the correct C/A code length should be within half of a sample.
If the rounding is not included in the calculation an error will result.
If the sampling frequency used for calculations is not the same as the sampling device errors will be introduced in the receiver.
Pseudorange = (Datapoint - DataPointMin) * SamplingFreq +.068
All of the pseudoranges will be scalled incorrectly depending on how far off the sampling frequency is.
See Adjusting the sampling frequency.