/// <summary>
/// 获取指定时刻的卫星位置，考虑了地球自转改正置。
/// </summary>
/// <param name="gpsTime"></param>
/// <param name="ephemeris"></param>
/// <returns></returns>
public static XYZ GetSatPosWithEarthRotateCorrection(Time gpsTime, Ephemeris ephemeris)
{
var dt = (ephemeris.Time - gpsTime); //相距参考时刻的秒数。
#region 方案1：顾及地球自转效应
//correction for earth rotation
double sinL = Math.Sin(RotateVelocityOfEarth * dt);
double cosL = Math.Cos(RotateVelocityOfEarth * dt);
double newX = cosL * ephemeris.XYZ.X - sinL * ephemeris.XYZ.Y;
double newY = sinL * ephemeris.XYZ.X + cosL * ephemeris.XYZ.Y;
double newZ = ephemeris.XYZ.Z;
XYZ newXyz = new XYZ(newX, newY, newZ);
#endregion
return(newXyz);
}
/// <summary>
/// 星历相减
/// </summary>
/// <param name="first"></param>
/// <param name="second"></param>
/// <returns></returns>
public static Ephemeris operator -(Ephemeris first, Ephemeris second)
{
if (first.Prn != second.Prn || first.Time != second.Time)
{
new Log(typeof(Ephemeris)).Error("不是同一卫星，不可相加，" + first + ", " + second);
return(first);
}
Ephemeris ephemeris = new Ephemeris(first.Prn, first.Time);
ephemeris.XYZ = first.XYZ - second.XYZ;
if (first.Rms != null && second.Rms != null)
{
// ephemeris.Rms = XYZ.RmsPlus(first.Rms, second.Rms);
}
ephemeris.XyzDot = first.XyzDot - second.XyzDot;
ephemeris.ClockBias = first.ClockBias - second.ClockBias;
ephemeris.ClockBiasRms = Utils.DoubleUtil.RmsPlus(first.ClockBiasRms, first.ClockBiasRms);
ephemeris.ClockDrift = first.ClockDrift - second.ClockDrift;
return(ephemeris);
}
/// <summary>
/// 用于比较排序。
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
public int CompareTo(Ephemeris other)
{
return((int)this.Time.CompareTo(other.Time));
}