Antti Lehtinen Doppler Positioning with GPS - Matematiikan laitos
Antti Lehtinen Doppler Positioning with GPS - Matematiikan laitos
Antti Lehtinen Doppler Positioning with GPS - Matematiikan laitos
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
3.4 <strong>Positioning</strong>ErrorAnalysis ...................... 13<br />
3.5 Limitationsofthe<strong>GPS</strong>........................ 14<br />
4 <strong>Doppler</strong> <strong>Positioning</strong> <strong>with</strong> the <strong>GPS</strong> 16<br />
4.1 Needfor<strong>Doppler</strong><strong>Positioning</strong>..................... 16<br />
4.2 Comparisonbetween<strong>GPS</strong>andTransit ............... 17<br />
4.3 TheGoverningEquations ...................... 18<br />
4.3.1 The<strong>Doppler</strong>ShiftEquation ................. 18<br />
4.3.2 TheClockDriftError .................... 20<br />
4.3.3 Mathematical Problem Formulation . . . . . . . . . . . . . 21<br />
4.4 SymbolicMethods .......................... 23<br />
4.4.1 Solvingthe Receiver Position . . . . . . . . . . . . . . . . 23<br />
4.4.2 Existence and Uniqueness Considerations . . . . . . . . . . 23<br />
4.5 StandardNumericalMethods .................... 24<br />
4.5.1 ProblemFormulation..................... 24<br />
4.5.2 TheNewtonMethod ..................... 25<br />
4.5.3 TheGauss-NewtonMethod ................. 26<br />
4.5.4 CalculatingtheDerivativeMatrix.............. 27<br />
4.6 ProblemSpecificIterativeMethods ................. 30<br />
5 <strong>Positioning</strong> Performance 31<br />
5.1 MeasurementNoise.......................... 31<br />
5.1.1 IonosphericEffects ...................... 31<br />
5.1.2 Receiver Noise . . . . . . . . . . . . . . . . . . . . . . . . . 32<br />
5.1.3 UnknownUserVelocity.................... 32<br />
5.1.4 BiasedTimeEstimate .................... 34<br />
5.2 <strong>Positioning</strong>Accuracy......................... 35<br />
5.2.1 Effect of Measurement Errors on <strong>Positioning</strong>Solution . . . 35<br />
5.2.2 <strong>Doppler</strong> Dilution of Precision . . . . . . . . . . . . . . . . 36<br />
iii