```
public class PseudorangeCalculator

                    
```
Pseudorange Calculator
Calculates pseudoranges from raw GNSS measurements. Based on Google's GPS Tools best practices and ICD-GPS-200 specification.
Pseudorange is the distance from receiver to satellite, calculated from:
- Receiver time (from GnssClock)
- Satellite transmit time (from GnssMeasurement)
- Speed of light
Includes:
- Week rollover correction
- Clock bias handling
- State filtering for quality control

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`public final class`	`PseudorangeCalculator.MeasurementQuality`	Data class for measurement quality metrics.

Field Summary

Fields
Modifier and Type	Field	Description
`public final static PseudorangeCalculator`	`INSTANCE`

Method Summary

Modifier and Type	Method	Description
`final Pair<Double, Double>`	`calculatePseudorange(GnssMeasurement measurement, GnssClock clock)`	Calculate pseudorange from GNSS measurement and clock.
`final Boolean`	`isMeasurementValid(GnssMeasurement measurement)`	Check if a measurement is valid for pseudorange calculation.
`final Double`	`calculateGpsTime(GnssMeasurement measurement, GnssClock clock)`	Calculate GPS time from measurement and clock.
`final Pair<Integer, Double>`	`calculateGpsWeekAndTow(GnssClock clock)`	Calculate GPS week and time-of-week from clock.
`final Pair<Double, Double>`	`calculatePseudorangeRate(GnssMeasurement measurement)`	Calculate pseudorange rate (Doppler-derived velocity).
`final Double`	`calculateCarrierPhase(GnssMeasurement measurement)`	Calculate carrier phase if available.
`final Pair<Double, Double>`	`calculateAccumulatedDeltaRange(GnssMeasurement measurement)`	Calculate accumulated delta range (integrated carrier phase).
`final Boolean`	`isAccumulatedDeltaRangeValid(GnssMeasurement measurement)`	Check if accumulated delta range state is valid.
`final Double`	`calculateGeometricRange(Vector3D satPos, Vector3D userPos)`	Calculate geometric range from satellite position to user position.
`final Double`	`calculatePseudorangeResidual(Double measuredPseudorange, Double geometricRange, Double receiverClockBias, Double satelliteClockBias)`	Calculate pseudorange residual.
`final PseudorangeCalculator.MeasurementQuality`	`getMeasurementQuality(GnssMeasurement measurement)`	Get quality metrics for a measurement.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - calculatePseudorange
```
@RequiresApi(value = 24) final Pair<Double, Double> calculatePseudorange(GnssMeasurement measurement, GnssClock clock)
```
    Calculate pseudorange from GNSS measurement and clock.
    
    Parameters:
    
    measurement - GnssMeasurement from Android API
    
    clock - GnssClock from Android API
  - isMeasurementValid
```
@RequiresApi(value = 24) final Boolean isMeasurementValid(GnssMeasurement measurement)
```
    Check if a measurement is valid for pseudorange calculation.
    Requirements:
    Code lock acquired
    Time reference decoded (TOW for GPS/Galileo/BeiDou, TOD for GLONASS, or known from previous fix)
    Sufficient signal strength (CN0)
  - calculateGpsTime
```
@RequiresApi(value = 24) final Double calculateGpsTime(GnssMeasurement measurement, GnssClock clock)
```
    Calculate GPS time from measurement and clock.
    
    Parameters:
    
    measurement - GnssMeasurement
    
    clock - GnssClock
  - calculateGpsWeekAndTow
```
@RequiresApi(value = 24) final Pair<Integer, Double> calculateGpsWeekAndTow(GnssClock clock)
```
    Calculate GPS week and time-of-week from clock.
    
    Parameters:
    
    clock - GnssClock
  - calculatePseudorangeRate
```
@RequiresApi(value = 24) final Pair<Double, Double> calculatePseudorangeRate(GnssMeasurement measurement)
```
    Calculate pseudorange rate (Doppler-derived velocity). This is directly available from GnssMeasurement.
    
    Parameters:
    
    measurement - GnssMeasurement
  - calculateCarrierPhase
```
@RequiresApi(value = 24) final Double calculateCarrierPhase(GnssMeasurement measurement)
```
    Calculate carrier phase if available. Carrier phase is more accurate than code phase for positioning.
    
    Parameters:
    
    measurement - GnssMeasurement
  - calculateAccumulatedDeltaRange
```
@RequiresApi(value = 24) final Pair<Double, Double> calculateAccumulatedDeltaRange(GnssMeasurement measurement)
```
    Calculate accumulated delta range (integrated carrier phase). Useful for precise positioning.
    
    Parameters:
    
    measurement - GnssMeasurement
  - isAccumulatedDeltaRangeValid
```
@RequiresApi(value = 24) final Boolean isAccumulatedDeltaRangeValid(GnssMeasurement measurement)
```
    Check if accumulated delta range state is valid. Valid ADR can be used for carrier phase positioning.
  - calculateGeometricRange
```
 final Double calculateGeometricRange(Vector3D satPos, Vector3D userPos)
```
    Calculate geometric range from satellite position to user position. Used for residual calculation and quality control.
    
    Parameters:
    
    satPos - Satellite position ECEF (meters)
    
    userPos - User position ECEF (meters)
  - calculatePseudorangeResidual
```
 final Double calculatePseudorangeResidual(Double measuredPseudorange, Double geometricRange, Double receiverClockBias, Double satelliteClockBias)
```
    Calculate pseudorange residual. Residual = measured pseudorange - (geometric range + clock bias + satellite clock error)
    
    Parameters:
    
    measuredPseudorange - Measured pseudorange in meters
    
    geometricRange - Calculated geometric range in meters
    
    receiverClockBias - Receiver clock bias in meters
    
    satelliteClockBias - Satellite clock bias in seconds
  - getMeasurementQuality
```
@RequiresApi(value = 24) final PseudorangeCalculator.MeasurementQuality getMeasurementQuality(GnssMeasurement measurement)
```
    Get quality metrics for a measurement.

Object PseudorangeCalculator

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Method Detail

calculatePseudorange

isMeasurementValid

calculateGpsTime

calculateGpsWeekAndTow

calculatePseudorangeRate

calculateCarrierPhase

calculateAccumulatedDeltaRange

isAccumulatedDeltaRangeValid

calculateGeometricRange

calculatePseudorangeResidual

getMeasurementQuality