// // SxP4Test.cpp // This sample code demonstrates how to use the C++ classes in order // to determine satellite position and look angles. // // mfh 12/07/2003 // #include "stdafx.h" #include #include "cTle.h" #include "cEci.h" #include "cOrbit.h" #include "cSite.h" ///////////////////////////////////////////////////////////////////////////// // Test routine to output position and velocity information void PrintPosVel(const cTle &tle) { cOrbit orbit(tle); cEci eci; vector Pos; // Calculate position, velocity // mpe = "minutes past epoch" for (int mpe = 0; mpe <= (360 * 4); mpe += 360) { // Get the position of the satellite at time "mpe" // The coordinates are placed into the local variable "eci". orbit.getPosition(mpe, &eci); // Push the coordinates object onto the end of the vector. Pos.push_back(eci); } // Print TLE data printf("%s\n", tle.getName().c_str()); printf("%s\n", tle.getLine1().c_str()); printf("%s\n\n", tle.getLine2().c_str()); // Header printf(" TSINCE X Y Z\n\n"); // Iterate over each of the ECI position objects pushed onto the // position vector, above, printing the ECI position information // as we go. for (unsigned int i = 0; i < Pos.size(); i++) { printf("%8d.00 %16.8f %16.8f %16.8f\n", i * 360, Pos[i].getPos().m_x, Pos[i].getPos().m_y, Pos[i].getPos().m_z); } printf("\n XDOT YDOT ZDOT\n\n"); // Iterate over each of the ECI position objects in the position // vector again, but this time print the velocity information. for (unsigned int i = 0; i < Pos.size(); i++) { printf(" %16.8f %16.8f %16.8f\n", Pos[i].getVel().m_x, Pos[i].getVel().m_y, Pos[i].getVel().m_z); } } ////////////////////////////////////////////////////////////////////////////// int main(int argc, char* argv[]) { // Test SGP4 string str1 = "SGP4 Test"; string str2 = "1 88888U 80275.98708465 .00073094 13844-3 66816-4 0 8"; string str3 = "2 88888 72.8435 115.9689 0086731 52.6988 110.5714 16.05824518 105"; cTle tle1(str1, str2, str3); PrintPosVel(tle1); printf("\n"); // Test SDP4 str1 = "SDP4 Test"; str2 = "1 11801U 80230.29629788 .01431103 00000-0 14311-1 8"; str3 = "2 11801 46.7916 230.4354 7318036 47.4722 10.4117 2.28537848 6"; cTle tleSDP4(str1, str2, str3); PrintPosVel(tleSDP4); printf("\nExample output:\n"); // Example: Define a location on the earth, then determine the look-angle // to the SDP4 satellite defined above. // Create an orbit object using the SDP4 TLE object. cOrbit orbitSDP4(tleSDP4); // Create an ECI object to hold the location of the satellite cEci eciSDP4; // Get the location of the satellite from the Orbit object. The // earth-centered inertial information is placed into eciSDP4. // Here we ask for the location of the satellite 90 minutes after // the TLE epoch. orbitSDP4.getPosition(90.0, &eciSDP4); // Now create a site object. Site objects represent a location on the // surface of the earth. Here we arbitrarily select a point on the // equator. cSite siteEquator(0.0, -100.0, 0); // 0.00 N, 100.00 W, 0 km altitude // Now get the "look angle" from the site to the satellite. // Note that the ECI object "eciSDP4" contains a time associated // with the coordinates it contains; this is the time at which // the look angle is valid. cCoordTopo topoLook = siteEquator.getLookAngle(eciSDP4); // Print out the results. Note that the Azimuth and Elevation are // stored in the cCoordTopo object as radians. Here we convert // to degrees using rad2deg() printf("AZ: %.1f EL: %.1f\n", rad2deg(topoLook.m_Az), rad2deg(topoLook.m_El)); }