/// <summary>
/// 计算卫星在信号发射时的位置
/// </summary>
/// <param name="n_FileData">星历数据</param>
/// <param name="satSendTime">卫星信号发射的时间</param>
/// <returns>卫星在地心坐标系中的空间直角坐标</returns>
public Position SatellitePosition(N_FileData n_FileData, GPSTime satSendTime)
{
Position satPosition = new Position();
double A, n0, tk, n, Mk, Ek, E0, f, uu, omega_uk, omega_rk, omega_ik, uk, rk, ik, xk, yk, Lk;
A = Math.Pow(n_FileData.SqrtA, 2);//轨道长半轴
n0 = Math.Sqrt((Constant.GM / Math.Pow(A, 3)));
tk = satSendTime.GPSWeek * 604800 + satSendTime.GPSSecond - n_FileData.GPSWeek * 604800 - n_FileData.TOE;
if (tk > 302400)
{
tk = tk - 604800;
}
else if (tk < -302400)
{
tk = tk + 604800;
}
n = n0 + n_FileData.DetlaN;
Mk = n_FileData.M0 + n * tk;
E0 = Mk;
Ek = Mk + n_FileData.E * Math.Sin(E0);
while (Math.Abs(Ek - E0) > Math.Pow(10, -12))
{
E0 = Ek;
Ek = Mk + n_FileData.E * Math.Sin(E0);
}
f = Math.Atan2((Math.Sqrt(1 - Math.Pow(n_FileData.E, 2))) * Math.Sin(Ek), Math.Cos(Ek) - n_FileData.E);
uu = f + n_FileData.OmegaLow;
omega_uk = n_FileData.Cus * Math.Sin(2 * uu) + n_FileData.Cuc * Math.Cos(2 * uu);
omega_rk = n_FileData.Crs * Math.Sin(2 * uu) + n_FileData.Crc * Math.Cos(2 * uu);
omega_ik = n_FileData.Cis * Math.Sin(2 * uu) + n_FileData.Cic * Math.Cos(2 * uu);
uk = uu + omega_uk;
rk = A * (1 - n_FileData.E * Math.Cos(Ek)) + omega_rk;
ik = n_FileData.I0 + omega_ik + n_FileData.IDot * tk;
xk = rk * Math.Cos(uk);
yk = rk * Math.Sin(uk);
Lk = n_FileData.Omega + (n_FileData.OmegaDot - Constant.OmegaDotE) * tk - Constant.OmegaDotE * n_FileData.TOE;
satPosition.XX = xk * Math.Cos(Lk) - yk * Math.Cos(ik) * Math.Sin(Lk);
satPosition.YY = xk * Math.Sin(Lk) + yk * Math.Cos(ik) * Math.Cos(Lk);
satPosition.ZZ = yk * Math.Sin(ik);
return(satPosition);
}
//public double LastEpochX;
//public double LastEpochY;
//public double LastEpochZ;
/// <summary>
/// 读取N文件
/// </summary>
public bool Read_N_File()
{
string path;//打开文件路径
OpenFileDialog ofd = new OpenFileDialog();
ofd.Title = "选择导航电文文件";
ofd.Filter = "N文件|*.*n|所有文件|*.*";
if (ofd.ShowDialog() == DialogResult.OK)
{
path = ofd.FileName;
}
else
{
return(false);
}
//清除
N_FileSum.n_FileHeadSum = null;
N_FileSum.n_FileDataSum.Clear();
StreamReader n_FileReader = new StreamReader(path);
string n_FileLine;//储存读到的每一行
n_FileLine = n_FileReader.ReadLine();
while (n_FileLine != null)
{
/**************************************读取头文件********************************************/
while (n_FileLine.Trim() != "END OF HEADER")
{
string tempStr = n_FileLine.Substring(60, n_FileLine.Length - 60);//用于判断内容的部分
switch (tempStr.Trim())
{
case "ION ALPHA":
n_FileHead.Ion_Alpha = new double[4];
n_FileHead.Ion_Alpha[0] = double.Parse(n_FileLine.Substring(2, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(11, 3)));
n_FileHead.Ion_Alpha[1] = double.Parse(n_FileLine.Substring(14, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(23, 3)));
n_FileHead.Ion_Alpha[2] = double.Parse(n_FileLine.Substring(26, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(35, 3)));
n_FileHead.Ion_Alpha[3] = double.Parse(n_FileLine.Substring(38, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(47, 3)));
break;
case "ION BETA":
n_FileHead.Ion_Beta = new double[4];
n_FileHead.Ion_Beta[0] = double.Parse(n_FileLine.Substring(2, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(11, 3)));
n_FileHead.Ion_Beta[1] = double.Parse(n_FileLine.Substring(14, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(23, 3)));
n_FileHead.Ion_Beta[2] = double.Parse(n_FileLine.Substring(26, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(35, 3)));
n_FileHead.Ion_Beta[3] = double.Parse(n_FileLine.Substring(38, 8)) * Math.Pow(10, double.Parse(n_FileLine.Substring(47, 3)));
break;
case "DELTA-UTC: A0,A1,T,W":
n_FileHead.A0 = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
n_FileHead.A1 = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileHead.T = int.Parse(n_FileLine.Substring(41, 9));
n_FileHead.W = int.Parse(n_FileLine.Substring(50, 9));
break;
case "LEAP SECONDS":
n_FileHead.Leap_Seconds = int.Parse(n_FileLine.Substring(0, 6));
break;
} //swich
n_FileLine = n_FileReader.ReadLine();
} //while (n_FileLine != "END OF HEADER")
N_FileSum.n_FileHeadSum = n_FileHead;//读出的值存入N_FileSum
/**************************************读取数据文件********************************************/
n_FileLine = n_FileReader.ReadLine();
int i = 0;
while (n_FileLine != null)
{
switch (i)
{
case 0:
n_FileData.PRN = int.Parse(n_FileLine.Substring(0, 2).Trim());
n_FileData.TOC.Year = int.Parse(n_FileLine.Substring(3, 2)) + 2000;
n_FileData.TOC.Month = int.Parse(n_FileLine.Substring(5, 3));
n_FileData.TOC.Day = int.Parse(n_FileLine.Substring(8, 3));
n_FileData.TOC.Hour = int.Parse(n_FileLine.Substring(11, 3));
n_FileData.TOC.Minute = int.Parse(n_FileLine.Substring(14, 3));
n_FileData.TOC.Second = double.Parse(n_FileLine.Substring(17, 5));
n_FileData.ClkBias = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileData.ClkDrift = double.Parse(n_FileLine.Substring(41, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(57, 3)));
n_FileData.ClkDriftRate = double.Parse(n_FileLine.Substring(60, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(76, 3)));
break;
case 1:
n_FileData.IODE = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
n_FileData.Crs = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileData.DetlaN = double.Parse(n_FileLine.Substring(41, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(57, 3)));
n_FileData.M0 = double.Parse(n_FileLine.Substring(60, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(76, 3)));
break;
case 2:
n_FileData.Cuc = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
n_FileData.E = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileData.Cus = double.Parse(n_FileLine.Substring(41, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(57, 3)));
n_FileData.SqrtA = double.Parse(n_FileLine.Substring(60, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(76, 3)));
break;
case 3:
n_FileData.TOE = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
n_FileData.Cic = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileData.Omega = double.Parse(n_FileLine.Substring(41, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(57, 3)));
n_FileData.Cis = double.Parse(n_FileLine.Substring(60, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(76, 3)));
break;
case 4:
n_FileData.I0 = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
n_FileData.Crc = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileData.OmegaLow = double.Parse(n_FileLine.Substring(41, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(57, 3)));
n_FileData.OmegaDot = double.Parse(n_FileLine.Substring(60, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(76, 3)));
break;
case 5:
n_FileData.IDot = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
n_FileData.CodesOnL2Channel = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileData.GPSWeek = double.Parse(n_FileLine.Substring(41, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(57, 3)));
n_FileData.L2PDataFlag = double.Parse(n_FileLine.Substring(60, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(76, 3)));
break;
case 6:
n_FileData.SVAccuracy = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
n_FileData.SVHealth = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));
n_FileData.TGD = double.Parse(n_FileLine.Substring(41, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(57, 3)));
n_FileData.IODC = double.Parse(n_FileLine.Substring(60, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(76, 3)));
break;
case 7:
n_FileData.TransTimeOfMsg = double.Parse(n_FileLine.Substring(3, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(19, 3)));
//n_FileData.Spare1 = double.Parse(n_FileLine.Substring(22, 15)) * Math.Pow(10, double.Parse(n_FileLine.Substring(38, 3)));//有的文件没有这个数据，会报错。
break;
}//switch (i)
i = i + 1;
i = i % 8;
if (i == 0)
{
N_FileSum.n_FileDataSum.Add(n_FileData);//读出的值存入N_FileSum
n_FileData = new N_FileData();
}
n_FileLine = n_FileReader.ReadLine();
} //while (n_FileLine != null)
} //while (n_FileLine != null)
return(true);
}
