/** \brief SGP4SDP4 driver for doing AOS/LOS calculations.
* \param sat Pointer to the satellite data.
* \param qth Pointer to the QTH data.
* \param t The time for calculation (Julian Date)
*
*/
void
predict_calc (sat_t *sat, qth_t *qth, gdouble t)
{
obs_set_t obs_set;
geodetic_t sat_geodetic;
geodetic_t obs_geodetic;
double age;
obs_geodetic.lon = qth->lon * de2ra;
obs_geodetic.lat = qth->lat * de2ra;
obs_geodetic.alt = qth->alt / 1000.0;
obs_geodetic.theta = 0;
sat->jul_utc = t;
sat->tsince = (sat->jul_utc - sat->jul_epoch) * xmnpda;
/* call the norad routines according to the deep-space flag */
if (sat->flags & DEEP_SPACE_EPHEM_FLAG)
SDP4 (sat, sat->tsince);
else
SGP4 (sat, sat->tsince);
Convert_Sat_State (&sat->pos, &sat->vel);
/* get the velocity of the satellite */
Magnitude (&sat->vel);
sat->velo = sat->vel.w;
Calculate_Obs (sat->jul_utc, &sat->pos, &sat->vel, &obs_geodetic, &obs_set);
Calculate_LatLonAlt (sat->jul_utc, &sat->pos, &sat_geodetic);
while (sat_geodetic.lon < -pi)
sat_geodetic.lon += twopi;
while (sat_geodetic.lon > (pi))
sat_geodetic.lon -= twopi;
sat->az = Degrees (obs_set.az);
sat->el = Degrees (obs_set.el);
sat->range = obs_set.range;
sat->range_rate = obs_set.range_rate;
sat->ssplat = Degrees (sat_geodetic.lat);
sat->ssplon = Degrees (sat_geodetic.lon);
sat->alt = sat_geodetic.alt;
sat->ma = Degrees (sat->phase);
sat->ma *= 256.0/360.0;
sat->phase = Degrees (sat->phase);
/* 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;
}
static int compute_new_state_vect( const tle_t *tle, double *state_vect,
const int ephem)
{
double sat_params[N_SAT_PARAMS];
int rval = 0;
switch( ephem)
{
case 0:
SGP_init( sat_params, tle);
rval = SGP( 0., tle, sat_params, state_vect, state_vect + 3);
break;
case 1:
SGP4_init( sat_params, tle);
rval = SGP4( 0., tle, sat_params, state_vect, state_vect + 3);
break;
case 2:
SGP8_init( sat_params, tle);
rval = SGP8( 0., tle, sat_params, state_vect, state_vect + 3);
break;
case 3:
SDP4_init( sat_params, tle);
rval = SDP4( 0., tle, sat_params, state_vect, state_vect + 3);
break;
case 4:
SDP8_init( sat_params, tle);
rval = SDP8( 0., tle, sat_params, state_vect, state_vect + 3);
break;
default:
printf( "??? ephem = %d\n", ephem);
rval = -99;
break;
}
// if( rval)
// printf( "??? rval = %d; ecc = %.6lf\n", rval, tle->eo);
return( rval);
}
/* Main program */
int main( const int argc, const char **argv)
{
const char *tle_filename = ((argc == 1) ? "test.tle" : argv[1]);
FILE *ifile = fopen( tle_filename, "rb");
tle_t tle; /* Pointer to two-line elements set for satellite */
char line1[100], line2[100];
int ephem = 1; /* default to SGP4 */
int i; /* Index for loops etc */
int n_failures = 0, n_simple = 0, n_simplex = 0;
bool failures_only = false;
for( i = 2; i < argc; i++)
if( argv[i][0] == '-')
switch( argv[i][1])
{
case 'f':
failures_only = true;
break;
case 'v':
verbose = 1;
break;
case 'd':
dist_offset = atof( argv[i] + 2);
break;
case 's':
vel_offset = atof( argv[i] + 2);
break;
default:
printf( "Option '%s' unrecognized\n", argv[i]);
break;
}
if( !ifile)
{
printf( "Couldn't open input TLE file %s\n", tle_filename);
exit( -1);
}
*line1 = '\0';
while( fgets( line2, sizeof( line2), ifile))
{
int got_data = 0;
double state_vect[6];
set_tle_defaults( &tle);
if( strlen( line2) > 110 && line2[7] == '.' && line2[18] == '.'
&& line2[0] == '2' && line2[1] == '4')
{
got_data = 3; /* Find_Orb state vector ephemeris */
tle.epoch = atof( line2);
sscanf( line2 + 13, "%lf %lf %lf %lf %lf %lf",
state_vect + 0, state_vect + 1, state_vect + 2,
state_vect + 3, state_vect + 4, state_vect + 5);
}
else if( strlen( line1) > 55 && !memcmp( line1 + 50, " (TDB)", 6))
{ /* JPL Horizons vector */
const double obliq_2000 = 23.4392911 * PI / 180.;
tle.epoch = atof( line1); /* get JD epoch from header... */
strcpy( line1, line2);
if( fgets( line2, sizeof( line2), ifile))
got_data = 1;
sscanf( line1, "%lf %lf %lf",
state_vect + 0, state_vect + 1, state_vect + 2);
sscanf( line2, "%lf %lf %lf",
state_vect + 3, state_vect + 4, state_vect + 5);
/* Cvt ecliptic to equatorial 2000: */
rotate_vector( state_vect , obliq_2000, 0);
rotate_vector( state_vect + 3, obliq_2000, 0);
}
else if( parse_elements( line1, line2, &tle) >= 0)
got_data = 2;
if( got_data == 1 || got_data == 3)
tle.epoch -= 68.00 / 86400.; /* rough convert TDT to UTC */
if( got_data) /* hey! we got a TLE! */
{
double sat_params[N_SAT_PARAMS], trial_state[6];
int simple_rval;
bool failed = false;
tle_t new_tle;
if( got_data == 1 || got_data == 3)
{
ephem = 3; /* Use SDP4 for JPL Horizons vectors */
for( i = 0; i < 6 && fabs( state_vect[i]) < 1.; i++)
;
if( i == 6) /* all small quantities, must be in AU & AU/day : */
{
for( i = 0; i < 6; i++)
state_vect[i] *= AU_IN_KM;
for( i = 3; i < 6; i++)
state_vect[i] /= seconds_per_day;
}
for( i = 3; i < 6; i++) /* cvt km/sec to km/min */
state_vect[i] *= seconds_per_minute;
if( !failures_only)
show_results( "Before:", NULL, state_vect);
}
else
{
int is_deep = select_ephemeris( &tle);
if( is_deep && (ephem == 1 || ephem == 2))
ephem += 2; /* switch to an SDx */
if( !is_deep && (ephem == 3 || ephem == 4))
ephem -= 2; /* switch to an SGx */
/* Calling of NORAD routines */
/* Each NORAD routine (SGP, SGP4, SGP8, SDP4, SDP8) */
/* will be called in turn with the appropriate TLE set */
switch( ephem)
{
case 0:
SGP_init( sat_params, &tle);
SGP( 0., &tle, sat_params, state_vect, state_vect + 3);
break;
case 1:
SGP4_init( sat_params, &tle);
SGP4( 0., &tle, sat_params, state_vect, state_vect + 3);
break;
case 2:
SGP8_init( sat_params, &tle);
SGP8( 0., &tle, sat_params, state_vect, state_vect + 3);
break;
case 3:
SDP4_init( sat_params, &tle);
SDP4( 0., &tle, sat_params, state_vect, state_vect + 3);
break;
case 4:
SDP8_init( sat_params, &tle);
SDP8( 0., &tle, sat_params, state_vect, state_vect + 3);
break;
}
if( !failures_only)
show_results( "Before:", &tle, state_vect);
}
new_tle = tle;
simple_rval = compute_tle_from_state_vector( &new_tle, state_vect, ephem, trial_state);
if( simple_rval)
{
n_simplex++;
find_tle_via_simplex_method( &new_tle, state_vect, trial_state, ephem);
}
else
n_simple++;
compute_new_state_vect( &new_tle, trial_state, ephem);
for( i = 0; i < 6; i++)
{
trial_state[i] -= state_vect[i];
if( fabs( trial_state[i]) > 1e-6)
failed = true;
}
if( failed && failures_only)
show_results( "Before:", &tle, state_vect);
if( failed || !failures_only)
show_results( (simple_rval ? "Simplex result:" : "Simplest method:"),
&new_tle, trial_state);
if( failed)
n_failures++;
}
strcpy( line1, line2);
}
fclose( ifile);
printf( "%d solved with simple method; %d with simplex\n", n_simple, n_simplex);
if( n_failures)
printf( "%d failures\n", n_failures);
return(0);
} /* End of main() */
/** \brief Initialise satellite data.
* \param sat The satellite to initialise.
* \param qth Optional QTH info, use (0,0) if NULL.
*
* This function calculates the satellite data at t = 0, ie. epoch time
* The function is called automatically by gtk_sat_data_read_sat.
*/
void
gtk_sat_data_init_sat (sat_t *sat, qth_t *qth)
{
geodetic_t obs_geodetic;
obs_set_t obs_set;
geodetic_t sat_geodetic;
double jul_utc, age;
g_return_if_fail (sat != NULL);
jul_utc = Julian_Date_of_Epoch (sat->tle.epoch); // => tsince = 0.0
sat->jul_epoch = jul_utc;
/* initialise observer location */
if (qth != NULL) {
obs_geodetic.lon = qth->lon * de2ra;
obs_geodetic.lat = qth->lat * de2ra;
obs_geodetic.alt = qth->alt / 1000.0;
obs_geodetic.theta = 0;
}
else {
obs_geodetic.lon = 0.0;
obs_geodetic.lat = 0.0;
obs_geodetic.alt = 0.0;
obs_geodetic.theta = 0;
}
/* execute computations */
if (sat->flags & DEEP_SPACE_EPHEM_FLAG)
SDP4 (sat, 0.0);
else
SGP4 (sat, 0.0);
/* scale position and velocity to km and km/sec */
Convert_Sat_State (&sat->pos, &sat->vel);
/* get the velocity of the satellite */
Magnitude (&sat->vel);
sat->velo = sat->vel.w;
Calculate_Obs (jul_utc, &sat->pos, &sat->vel, &obs_geodetic, &obs_set);
Calculate_LatLonAlt (jul_utc, &sat->pos, &sat_geodetic);
while (sat_geodetic.lon < -pi)
sat_geodetic.lon += twopi;
while (sat_geodetic.lon > (pi))
sat_geodetic.lon -= twopi;
sat->az = Degrees (obs_set.az);
sat->el = Degrees (obs_set.el);
sat->range = obs_set.range;
sat->range_rate = obs_set.range_rate;
sat->ssplat = Degrees (sat_geodetic.lat);
sat->ssplon = Degrees (sat_geodetic.lon);
sat->alt = sat_geodetic.alt;
sat->ma = Degrees (sat->phase);
sat->ma *= 256.0/360.0;
sat->footprint = 2.0 * xkmper * acos (xkmper/sat->pos.w);
age = 0.0;
sat->orbit = (long) floor((sat->tle.xno * xmnpda/twopi +
age * sat->tle.bstar * ae) * age +
sat->tle.xmo/twopi) + sat->tle.revnum - 1;
/* orbit type */
sat->otype = get_orbit_type (sat);
}
/* Main program */
int
main(void)
{
/* TLE source file */
char tle_file[] = "./rax.txt";
/* Observer's geodetic co-ordinates. */
/* Lat North, Lon East in rads, Alt in km */
geodetic_t obs_geodetic = {0.7368, -1.4615, 0.251, 0.0};
/* Two-line Orbital Elements for the satellite */
tle_t tle ;
/* Zero vector for initializations */
vector_t zero_vector = {0,0,0,0};
/* Satellite position and velocity vectors */
vector_t vel = zero_vector;
vector_t pos = zero_vector;
/* Satellite Az, El, Range, Range rate */
vector_t obs_set;
/* Solar ECI position vector */
vector_t solar_vector = zero_vector;
/* Solar observed azi and ele vector */
vector_t solar_set;
/* Calendar date and time (UTC) */
struct tm utc;
/* Satellite's predicted geodetic position */
geodetic_t sat_geodetic;
double
tsince, /* Time since epoch (in minutes) */
jul_epoch, /* Julian date of epoch */
jul_utc, /* Julian UTC date */
eclipse_depth = 0, /* Depth of satellite eclipse */
/* Satellite's observed position, range, range rate */
sat_azi, sat_ele, sat_range, sat_range_rate,
/* Satellites geodetic position and velocity */
sat_lat, sat_lon, sat_alt, sat_vel,
/* Solar azimuth and elevation */
sun_azi, sun_ele;
/* Used for storing function return codes */
int flg;
char
ephem[5], /* Ephemeris in use string */
sat_status[12]; /* Satellite eclipse status */
/* Input one (first!) TLE set from file */
flg = Input_Tle_Set(tle_file, &tle);
/* Abort if file open fails */
if( flg == -1 )
{
printf(" File open failed - Exiting!\n");
exit(-1);
}
/* Print satellite name and TLE read status */
printf(" %s: ", tle.sat_name);
if( flg == -2 )
{
printf("TLE set bad - Exiting!\n");
exit(-2);
}
else
printf("TLE set good - Happy Tracking!\n");
/* Printout of tle set data for tests if needed */
/* printf("\n %s %s %i %i %i\n"
" %14f %10f %8f %8f\n"
" %8f %8f %9f %8f %8f %12f\n",
tle.sat_name, tle.idesg, tle.catnr, tle.elset, tle.revnum,
tle.epoch, tle.xndt2o, tle.xndd6o, tle.bstar,
tle.xincl, tle.xnodeo, tle.eo, tle.omegao, tle.xmo, tle.xno);
*/
/** !Clear all flags! **/
/* Before calling a different ephemeris */
/* or changing the TLE set, flow control */
/* flags must be cleared in main(). */
ClearFlag(ALL_FLAGS);
/** Select ephemeris type **/
/* Will set or clear the DEEP_SPACE_EPHEM_FLAG */
/* depending on the TLE parameters of the satellite. */
/* It will also pre-process tle members for the */
/* ephemeris functions SGP4 or SDP4 so this function */
/* must be called each time a new tle set is used */
select_ephemeris(&tle);
do /* Loop */
{
/* Get UTC calendar and convert to Julian */
UTC_Calendar_Now(&utc);
jul_utc = Julian_Date(&utc);
/* Convert satellite's epoch time to Julian */
/* and calculate time since epoch in minutes */
jul_epoch = Julian_Date_of_Epoch(tle.epoch);
tsince = (jul_utc - jul_epoch) * xmnpda;
/* Copy the ephemeris type in use to ephem string */
if( isFlagSet(DEEP_SPACE_EPHEM_FLAG) )
strcpy(ephem,"SDP4");
else
strcpy(ephem,"SGP4");
/* Call NORAD routines according to deep-space flag */
if( isFlagSet(DEEP_SPACE_EPHEM_FLAG) )
SDP4(tsince, &tle, &pos, &vel);
else
SGP4(tsince, &tle, &pos, &vel);
/* Scale position and velocity vectors to km and km/sec */
Convert_Sat_State( &pos, &vel );
/* Calculate velocity of satellite */
Magnitude( &vel );
sat_vel = vel.w;
/** All angles in rads. Distance in km. Velocity in km/s **/
/* Calculate satellite Azi, Ele, Range and Range-rate */
Calculate_Obs(jul_utc, &pos, &vel, &obs_geodetic, &obs_set);
/* Calculate satellite Lat North, Lon East and Alt. */
Calculate_LatLonAlt(jul_utc, &pos, &sat_geodetic);
/* Calculate solar position and satellite eclipse depth */
/* Also set or clear the satellite eclipsed flag accordingly */
Calculate_Solar_Position(jul_utc, &solar_vector);
Calculate_Obs(jul_utc,&solar_vector,&zero_vector,&obs_geodetic,&solar_set);
if( Sat_Eclipsed(&pos, &solar_vector, &eclipse_depth) )
SetFlag( SAT_ECLIPSED_FLAG );
else
ClearFlag( SAT_ECLIPSED_FLAG );
/* Copy a satellite eclipse status string in sat_status */
if( isFlagSet( SAT_ECLIPSED_FLAG ) )
strcpy( sat_status, "Eclipsed" );
else
strcpy( sat_status, "In Sunlight" );
/* Convert and print satellite and solar data */
sat_azi = Degrees(obs_set.x);
sat_ele = Degrees(obs_set.y);
sat_range = obs_set.z;
sat_range_rate = obs_set.w;
sat_lat = Degrees(sat_geodetic.lat);
sat_lon = Degrees(sat_geodetic.lon);
sat_alt = sat_geodetic.alt;
sun_azi = Degrees(solar_set.x);
sun_ele = Degrees(solar_set.y);
printf("\n Date: %02d/%02d/%04d UTC: %02d:%02d:%02d Ephemeris: %s"
"\n Azi=%6.1f Ele=%6.1f Range=%8.1f Range Rate=%6.2f"
"\n Lat=%6.1f Lon=%6.1f Alt=%8.1f Vel=%8.3f"
"\n Stellite Status: %s - Depth: %2.3f"
"\n Sun Azi=%6.1f Sun Ele=%6.1f\n",
utc.tm_mday, utc.tm_mon, utc.tm_year,
utc.tm_hour, utc.tm_min, utc.tm_sec, ephem,
sat_azi, sat_ele, sat_range, sat_range_rate,
sat_lat, sat_lon, sat_alt, sat_vel,
sat_status, eclipse_depth,
sun_azi, sun_ele);
sleep(1);
} /* End of do */
while( 1 ); /* This stops Compaq ccc 'unreachcode' warning! */
return(0);
} /* End of main() */
int main( const int argc, const char **argv)
{
const char *tle_file_name = "ALL_TLE.TXT";
FILE *ifile = fopen( argv[1], "rb"), *tle_file;
FILE *stations;
char line1[100], line2[100], buff[90];
double search_radius = .2; /* default to .2-degree search */
double lon = 0., rho_sin_phi = 0., rho_cos_phi = 0.;
char curr_mpc_code[4];
int i, debug_level = 0, show_non_mpc_report_lines = 0;
char prev_obj[20];
double prev_jd = 0., prev_ra = 0., prev_dec = 0.;
if( argc == 1)
error_exit( -2);
if( !ifile)
{
printf( "Couldn't open input file %s\n", argv[1]);
exit( -1);
}
stations = fopen( "ObsCodes.html", "rb");
if( !stations) /* perhaps stored with truncated extension? */
stations = fopen( "ObsCodes.htm", "rb");
if( !stations) /* Or as a text file? */
stations = fopen( "stations.txt", "rb");
if( !stations)
{
printf( "Failed to find MPC station list 'ObsCodes.html'\n");
printf( "This can be downloaded at:\n\n");
printf( "http://www.minorplanetcenter.org/iau/lists/ObsCodes.html\n");
exit( -1);
}
curr_mpc_code[0] = curr_mpc_code[3] = '\0';
for( i = 1; i < argc; i++)
if( argv[i][0] == '-')
switch( argv[i][1])
{
case 'r':
search_radius = atof( argv[i] + 2);
break;
case 't':
tle_file_name = argv[i] + 2;
break;
break;
case 'd':
debug_level = atoi( argv[i] + 2);
break;
case 'a':
show_non_mpc_report_lines = 1;
break;
default:
printf( "Unrecognized command-line option '%s'\n", argv[i]);
exit( -2);
break;
}
tle_file = fopen( tle_file_name, "rb");
if( !tle_file)
{
printf( "Couldn't open TLE file %s\n", tle_file_name);
exit( -1);
}
*prev_obj = '\0';
while( fgets( buff, sizeof( buff), ifile))
{
double target_ra, target_dec, jd;
if( !get_mpc_data( buff, &jd, &target_ra, &target_dec))
{
char preceding_line[80], line0[100];
double observer_loc[3], observer_loc2[3];
printf( "\n%s", buff);
if( !memcmp( prev_obj, buff, 12) && fabs( jd - prev_jd) < .3)
{
double motion, posn_ang;
if( !compute_motion( jd - prev_jd,
(target_ra - prev_ra) * cos( (prev_dec + target_dec) / 2.),
(target_dec - prev_dec), &motion, &posn_ang))
printf( " Object motion is %.3lf'/sec at PA %.1lf\n",
motion, posn_ang);
}
memcpy( prev_obj, buff, 12);
prev_ra = target_ra;
prev_dec = target_dec;
prev_jd = jd;
if( memcmp( curr_mpc_code, buff + 77, 3))
{
char tbuff[100];
int got_it = 0;
memcpy( curr_mpc_code, buff + 77, 3);
fseek( stations, 0L, SEEK_SET);
while( !got_it && fgets( tbuff, sizeof( tbuff), stations))
got_it = !memcmp( tbuff, curr_mpc_code, 3);
if( got_it)
sscanf( tbuff + 3, "%lf %lf %lf",
&lon, &rho_cos_phi, &rho_sin_phi);
if( !got_it)
printf( "FAILED to find MPC code %s\n", curr_mpc_code);
}
if( debug_level)
printf( "lon = %.5lf rho cos phi = %.5lf rho sin phi = %.5lf\n",
lon, rho_cos_phi, rho_sin_phi);
observer_cartesian_coords( jd,
lon * PI / 180., rho_cos_phi, rho_sin_phi, observer_loc);
observer_cartesian_coords( jd + TIME_EPSILON,
lon * PI / 180., rho_cos_phi, rho_sin_phi, observer_loc2);
fseek( tle_file, 0L, SEEK_SET);
*line0 = '\0';
if( fgets( line1, sizeof( line1), tle_file))
while( fgets( line2, sizeof( line2), tle_file))
{
tle_t tle; /* Structure for two-line elements set for satellite */
if( parse_elements( line1, line2, &tle) >= 0)
{ /* hey! we got a TLE! */
int is_deep = select_ephemeris( &tle);
double sat_params[N_SAT_PARAMS], radius, d_ra, d_dec;
double ra, dec, dist_to_satellite, t_since;
double pos[3]; /* Satellite position vector */
double unused_delta2;
if( debug_level > 1)
printf( "%s", line1);
t_since = (jd - tle.epoch) * 1440.;
if( is_deep)
{
SDP4_init( sat_params, &tle);
SDP4( t_since, &tle, sat_params, pos, NULL);
}
else
{
SGP4_init( sat_params, &tle);
SGP4( t_since, &tle, sat_params, pos, NULL);
}
if( debug_level > 1)
printf( "%s", line2);
if( debug_level > 2)
printf( " %.5lf %.5lf %.5lf\n", pos[0], pos[1], pos[2]);
get_satellite_ra_dec_delta( observer_loc, pos,
&ra, &dec, &dist_to_satellite);
if( debug_level > 3)
printf( "RA: %.5lf dec: %.5lf\n", ra * 180. / PI,
dec * 180. / PI);
epoch_of_date_to_j2000( jd, &ra, &dec);
d_ra = (ra - target_ra + PI * 4.);
while( d_ra > PI)
d_ra -= PI + PI;
d_dec = dec - target_dec;
radius = sqrt( d_ra * d_ra + d_dec * d_dec) * 180. / PI;
if( radius < search_radius) /* good enough for us! */
{
double arcmin_per_sec, posn_ang;
/* Compute position one second later, so we */
/* can show speed/PA of motion: */
t_since += TIME_EPSILON * 1440.;
if( is_deep)
SDP4( t_since, &tle, sat_params, pos, NULL);
else
SGP4( t_since, &tle, sat_params, pos, NULL);
get_satellite_ra_dec_delta( observer_loc2, pos,
&d_ra, &d_dec, &unused_delta2);
epoch_of_date_to_j2000( jd, &d_ra, &d_dec);
d_ra -= ra;
d_dec -= dec;
while( d_ra > PI)
d_ra -= PI + PI;
while( d_ra < -PI)
d_ra += PI + PI;
/* Put RA into 0 to 2pi range: */
if( !compute_motion( TIME_EPSILON, d_ra * cos( dec), d_dec,
&arcmin_per_sec, &posn_ang))
{
line1[8] = line1[16] = '\0';
memcpy( line1 + 30, line1 + 11, 6);
line1[11] = '\0';
printf( " %s = %s%s-%s",
line1 + 2, (line1[9] >= '6' ? "19" : "20"),
line1 + 9, line1 + 30);
printf( " e=%.2lf; P=%.1lf min; i=%.1lf",
tle.eo,
2. * PI / tle.xno,
tle.xincl * 180. / PI);
if( strlen( line0) < 30) /* object name given... */
printf( ": %s\n", line0); /* not all TLEs do this */
else
printf( "\n");
printf( " delta=%8.1lf km; offset=%5.2lf degrees; motion %6.3lf'/sec at PA=%.1lf\n",
dist_to_satellite, radius, arcmin_per_sec,
posn_ang);
/* "Speed" is displayed in arcminutes/second,
or in degrees/minute */
}
}
}
strcpy( preceding_line, line1);
strcpy( line0, line1);
strcpy( line1, line2);
for( i = 0; line0[i] >= ' '; i++)
;
line0[i] = '\0'; /* remove trailing CR/LF */
}
}
else if( show_non_mpc_report_lines)
printf( "%s", buff);
}
fclose( tle_file);
fclose( stations);
fclose( ifile);
return( 0);
} /* End of main() */
int main( const int argc, const char **argv)
{
FILE *ifile = fopen( argv[1], "rb");
char line1[100], line2[100];
const char *intl_id = NULL;
double step_size = .1;
int i, n_steps = 100;
if( !ifile)
{
printf( "Couldn't open input file\n");
exit( -1);
}
for( i = 1; i < argc; i++)
if( argv[i][0] == '-')
switch( argv[i][1])
{
case 'i':
intl_id = argv[i] + 2;
break;
case 'n':
n_steps = atoi( argv[i] + 2);
break;
default:
printf( "Unrecognized option '%s'\n", argv[i]);
break;
}
*line1 = '\0';
sxpx_set_implementation_param( SXPX_DUNDEE_COMPLIANCE, 1);
while( fgets( line2, sizeof( line2), ifile))
{
tle_t tle; /* Pointer to two-line elements set for satellite */
int err_val;
if( (!intl_id || !memcmp( intl_id, line1 + 9, 6))
&& (err_val = parse_elements( line1, line2, &tle)) >= 0)
{ /* hey! we got a TLE! */
int is_deep = select_ephemeris( &tle);
double sat_params[N_SAT_PARAMS], observer_loc[3];
if( err_val)
printf( "WARNING: TLE parsing error %d\n", err_val);
for( i = 0; i < 3; i++)
observer_loc[i] = '\0';
if( is_deep)
SDP4_init( sat_params, &tle);
else
SGP4_init( sat_params, &tle);
for( i = 0; i < n_steps; i++)
{
double ra, dec, dist_to_satellite;
double pos[3]; /* Satellite position vector */
double t_since = (double)( i - n_steps / 2) * step_size;
double jd = tle.epoch + t_since;
t_since *= 1440.;
if( is_deep)
err_val = SDP4( t_since, &tle, sat_params, pos, NULL);
else
err_val = SGP4( t_since, &tle, sat_params, pos, NULL);
if( err_val)
printf( "Ephemeris error %d\n", err_val);
get_satellite_ra_dec_delta( observer_loc, pos,
&ra, &dec, &dist_to_satellite);
epoch_of_date_to_j2000( jd, &ra, &dec);
printf( "%-14sC%13.5f %08.4f %+08.4f",
intl_id, jd, ra * 180. / PI, dec * 180. / PI);
printf( " TLEs 500\n");
}
}
strcpy( line1, line2);
}
fclose( ifile);
return( 0);
} /* End of main() */
