Added start of SatelliteOrbit object

Rewrite.vcxproj

@@ -80,6 +80,7 @@
     <ClCompile Include="Julian.cpp" />
     <ClCompile Include="main.cpp" />
     <ClCompile Include="Observer.cpp" />
+    <ClCompile Include="SatelliteOrbit.cpp" />
     <ClCompile Include="SGDP4.cpp" />
     <ClCompile Include="Timespan.cpp" />
     <ClCompile Include="Tle.cpp" />
@@ -92,6 +93,7 @@
     <ClInclude Include="Julian.h" />
     <ClInclude Include="Observer.h" />
     <ClInclude Include="SatelliteException.h" />
+    <ClInclude Include="SatelliteOrbit.h" />
     <ClInclude Include="SGDP4.h" />
     <ClInclude Include="Timespan.h" />
     <ClInclude Include="Tle.h" />

Rewrite.vcxproj.filters

@@ -45,6 +45,9 @@
     <ClCompile Include="Timespan.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="SatelliteOrbit.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="Coord.h">
@@ -77,5 +80,8 @@
     <ClInclude Include="Timespan.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="SatelliteOrbit.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>

SatelliteOrbit.cpp

@@ -0,0 +1,55 @@
+#include "SatelliteOrbit.h"
+
+SatelliteOrbit::SatelliteOrbit(void) {
+}
+
+SatelliteOrbit::~SatelliteOrbit(void) {
+}
+
+void SatelliteOrbit::SetTle(const Tle& tle) {
+
+    sgdp4_.SetTle(tle);
+}
+
+bool SatelliteOrbit::IsGeostationary() {
+#if 0
+    if (sgdp4_.MeanMotion() == 0.0)
+        return true;
+
+    /*
+    radius of apogee 
+    the distance from the centre of the planet to the point in the orbit furthest away from the planet
+    */
+    const double apogee_altitude = sgdp4_.RecoveredSemiMajorAxis() * (1.0 + sgdp4_.Eccentricity()) - Globals::XKMPER();
+
+    /*
+     * check if almost same speed as earth
+     * or altitude is over 35000 km
+     */
+    if (fabs(sgdp4_.MeanMotion() - Globals::OMEGA_E()) < 0.0005 || apogee_altitude > 35000)
+        return true;
+    else
+#endif
+        return false;
+}
+
+unsigned int SatelliteOrbit::GetOrbitNumber(const Julian& jul) const{
+#if 0
+    double diff = jul.SpanMin(sgdp4_.Epoch());
+    
+    return (unsigned int)floor((sgdp4_.MeanMotion() * 1440.0 / Globals::TWOPI() +
+        diff * sgdp4_.BStar() * Globals::AE()) * diff +
+        sgdp4_.MeanAnomoly() / Globals::TWOPI()) + sgdp4_.OrbitNumber() - 1.0;
+#endif
+    return 0;
+}
+
+#if 0
+/* same formulas, but the one from predict is nicer */
+//sat->footprint = 2.0 * xkmper * acos (xkmper/sat->pos.w);
+sat->footprint = 12756.33 * acos(xkmper / (xkmper + sat->alt));
+age = sat->jul_utc - sat->jul_epoch;
+sat->orbit = (long) floor((sat->tle.xno * xmnpda / twopi +
+        age * sat->tle.bstar * ae) * age +
+        sat->tle.xmo / twopi) + sat->tle.revnum - 1;
+#endif

SatelliteOrbit.h

@@ -0,0 +1,23 @@
+#ifndef SATELLITEORBIT_H_
+#define SATELLITEORBIT_H_
+
+#include "Tle.h"
+#include "SGDP4.h"
+
+class SatelliteOrbit {
+public:
+    SatelliteOrbit(void);
+    virtual ~SatelliteOrbit(void);
+
+    void SetTle(const Tle& tle);
+
+    bool IsGeostationary();
+
+    unsigned int GetOrbitNumber(const Julian& jul) const;
+
+private:
+    SGDP4 sgdp4_;
+};
+
+#endif
+

main.cpp

@@ -9,7 +9,18 @@
 #include <string>
 #include <iomanip>
 
-void RunTest();
+void FindSatellite(const Julian& time_start, const Julian& time_end) {
+
+    /*
+     * half a second
+     */
+    static const double delta = 1.0 / (60.0 * 60.0 * 24.0 * 2.0);
+
+    //while (fabs(time_end - time_start) > delta) {
+
+    //}
+
+}
 
 void GeneratePassList(const CoordGeodetic& geo, const SGDP4& model, const Julian& date) {
     Observer obs(geo);
@@ -18,12 +29,17 @@ void GeneratePassList(const CoordGeodetic& geo, const SGDP4& model, const Julian
 
     CoordTopographic topo = obs.GetLookAngle(eci);
 
-    Julian date_start;
-    Julian date_end;
+    /*
+     * set start and end date
+     */
+    Julian time0 = date;
+    Julian time1 = date;
+    time1.AddDay(10.0);
 
-    date_end.AddDay(10.0);
-
-    for (Julian jd = date_start; jd <= date_end; jd.AddMin(1.0)) {
+    /*
+     * step throw period with 1 minute increments
+     */
+    for (Julian jd = date; jd <= time1; jd.AddMin(1.0)) {
 
     }
 }
@@ -46,3 +62,72 @@ int main() {
     return 0;
 }
 
+#if 0
+
+http://olifantasia.com/projects/gnuradio/mdvh/weather_sat/weather_sat_scripts_without_capture_files_2010061701/decoding/poes-weather-hrpt-decoder/hrpt-decoder-1.0.0.2/satellite/predict/
+
+xmnpda = 1440.0
+
+    /* same formulas, but the one from predict is nicer */
+    //sat->footprint = 2.0 * xkmper * acos (xkmper/sat->pos.w);
+    sat->footprint = 12756.33 * acos (xkmper / (xkmper+sat->alt));
+    age = sat->jul_utc - sat->jul_epoch;
+    sat->orbit = (long) floor((sat->tle.xno * xmnpda/twopi +
+                    age * sat->tle.bstar * ae) * age +
+                    sat->tle.xmo/twopi) + sat->tle.revnum - 1;
+
+bool TSat::IsGeostationary(void)
+{
+ /* This function returns a 1 if the satellite
+    appears to be in a geostationary orbit
+
+    Circular orbit at an altitude of 35 800 km over the equator.
+    A satellite moving with the Earth's rotation in a geostationary
+    orbit has a period of 23 hours, 56 minutes and 4 seconds.
+ */
+ double sma, aalt;
+
+  if(meanmo == 0.0)
+     return true;
+
+  sma  = 331.25*exp(log(1440.0/meanmo)*(2.0/3.0));
+  aalt = sma*(1.0+eccn)-xkmper;
+
+  if(fabs(meanmo-omega_E) < 0.0005 || // allmost same speed as earth
+     aalt > 35000)                    // altitude is over 35000 km
+     return true;
+  else
+     return false;
+}
+
+// latitude in radians
+bool TSat::DoesRise(double lat)
+{
+ /* This function returns a true if the satellite can ever rise
+    above the horizon of the ground station.
+*/
+ double lin, sma, apogee;
+ bool rc = false;
+
+  if(meanmo == 0.0)
+     return rc;
+  else {
+     lin = incl;
+
+     if(lin >= 90.0)
+        lin=180.0-lin;
+
+     sma    = 331.25*exp(log(1440.0/meanmo)*(2.0/3.0));
+     apogee = sma*(1.0+eccn)-xkmper;
+
+     if((acos2(xkmper/(apogee+xkmper))+lin*deg2rad) > fabs(lat))
+        rc = true;
+     else
+  	rc = false;
+  }
+
+ return rc;
+}
+
+#endif
+