public override void Correct(EpochSatellite epochSatellite)
{
if (IonoParamService == null)
{
return;
}
IIonoParam ionParam = IonoParamService.Get(epochSatellite.ReceiverTime);
if (ionParam == null)
{
return;
}
double correction = GetCorrectorInDistance(epochSatellite, ionParam);
this.Correction = correction;
if (IsCorrectionOnPhase)
{
this.Correction = -this.Correction;
}
// epochSatellite.SetCorrection(ErrorType, correction);
}
/// <summary>
/// 计算X，模型参数之一。phase (radians)
/// </summary>
/// <param name="ionParam"></param>
/// <param name="ionMLat">电离层穿刺点平均纬度，单位：半周</param>
/// <param name="tlocal"></param>
/// <returns></returns>
private static double GetX(IIonoParam ionParam, double ionMLat, double tlocal)
{
double per = GetPER(ionParam, ionMLat);
double x = 2.0 * PI * (tlocal - 50400.0) / per;
return(x);
}
/// <summary>
/// 计算PER，模型参数之一。period
/// </summary>
/// <param name="ionParam"></param>
/// <param name="ionMLat">电离层穿刺点平均纬度，单位：半周</param>
/// <returns></returns>
private static double GetPER(IIonoParam ionParam, double ionMLat)
{
double per = ionParam.BetaB0 +
ionParam.BetaB1 * ionMLat +
ionParam.BetaB2 * ionMLat * ionMLat +
ionParam.BetaB3 * ionMLat * ionMLat * ionMLat;
if (per < 72000.0)
{
per = 72000.0;
}
return(per);
}
/// <summary>
/// 计算AMP，模型参数之一。amplitude
/// </summary>
/// <param name="ionParam"></param>
/// <param name="ionMLat">电离层穿刺点平均纬度，单位：半周</param>
/// <returns></returns>
private static double GetAMP(IIonoParam ionParam, double ionMLat)
{
double amp = ionParam.AlfaA0 +
ionParam.AlfaA1 * ionMLat +
ionParam.AlfaA2 * ionMLat * ionMLat +
ionParam.AlfaA3 * ionMLat * ionMLat * ionMLat;
if (amp < 0.0)
{
//*******throw new Exception("amp limit="+amp);
amp = 0.0;
}
return(amp);
}
/// <summary>
/// 电离层模型改正。返回改正距离。 单位：米
/// </summary>
/// <param name="epochSatellite">卫星观测信息</param>
/// <param name="ionParam">电离层参数</param>
/// <returns></returns>
public static double GetCorrectorInDistance(EpochSatellite epochSatellite, IIonoParam ionParam)
{
if (ionParam == null)
{
return(0);
}
double correction = GetCorrectorInDistance(epochSatellite.RecevingTime.SecondsOfWeek,
epochSatellite.Ephemeris.XYZ,
epochSatellite.SiteInfo.EstimatedXyz,
ionParam);
return(correction);
}
/// <summary>
/// 电离层模型改正。返回时间延迟，单位：秒。
/// broadcast iono (coeff.v. icd-200)
/// input time: fraction of ut (or gps time of secondOfWeek) (machts nicht)
/// </summary>
/// <param name="weekSecond">周秒</param>
/// <param name="satXyz">卫星位置</param>
/// <param name="rcvXyz">接收机位置</param>
/// <returns>time delay in fraction</returns>
public static double IonoCorrection(double weekSecond, XYZ satXyz, XYZ rcvXyz, IIonoParam ionParam)
{
//*** divide by pi to funcKeyToDouble radians to semicircles
Polar p = CoordTransformer.XyzToGeoPolar(satXyz, rcvXyz, AngleUnit.Radian); //myV.GetLocalPolar(rxPos);
//azimuth angle between the user and satellite, measured clockwise positive from the true North (semi-circles)
double A = p.Azimuth; // 只参与三角计算，故单位为弧度radians here
//elevation angle between the user and satellite (semi-circles)
double E = p.Elevation / PI; //半周
GeoCoord geo = CoordTransformer.XyzToGeoCoord(rcvXyz, AngleUnit.Radian);
double rcvLat = geo.Lat / PI; //半周
double rcvLon = geo.Lon / PI; //半周
//earth's central angle between the user position and the earth projection of ionospheric intersection point (semi-circles)
double psi = GetEarthsCentralAngle(E);
double inoLat = GetIonLat(A, rcvLat, psi);
double inoLon = GetIonLon(A, rcvLon, psi, inoLat);
double ionMLat = GetMeanIonLat(inoLat, inoLon);
//*** local time from gps or ut time
double tlocal = GetLocalTime(weekSecond, inoLon);
//*** magnification factor, amplitude, and period
double f = GetF(E);
double amp = GetAMP(ionParam, ionMLat);
double x = GetX(ionParam, ionMLat, tlocal);
return(GetTimeDelay(f, amp, x));
}
/// <summary>
/// 电离层模型改正。返回改正距离。 单位：米
/// Tiono is referred to the L1 frequency; if the user is operating on the L2 frequency,
/// the correction term must be multiplied by γ (reference paragraph 20.3.3.3.3.2),
/// </summary>
/// <param name="weekSecond">周秒</param>
/// <param name="satXyz">卫星位置</param>
/// <param name="receiverXyz">接收机位置</param>
/// <param name="ionParam">电离层参数</param>
/// <returns> </returns>
public static double GetCorrectorInDistance(double weekSecond, XYZ satXyz, XYZ receiverXyz, IIonoParam ionParam)
{
if (ionParam == null)
{
return(0);
}
return(GnssConst.LIGHT_SPEED * IonoCorrection(weekSecond, satXyz, receiverXyz, ionParam));
}
