I would like to know about Sirf 3 navigation problems
The differences between measure pseudorange and calculated pseudorange are about +/- 15 m. I calculated the difference as follows
difference=(measured pseudorange)- (geometric range+receiver clock bias-satellite clock bias +Ionospheric correction+ tropospheric correction) All values except tropospheric correction are obtained from MID 28,30,41 .
Let me know how to solve this difference?
I am trying to write positioning algorithm using both Least square method and Kalman filter. I think the random error in positioning result can be remove by stochastic modeling but I have no idea to remove the dc offset due to pseudorange error.
I would like to know that how to calculate the signal travel time from sirf3 messages (MID 28,30).