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Make antenna radiation calculations selectable via switch

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This commit is contained in:
adrian 2011-12-05 11:43:21 +02:00
parent d8e4f8035d
commit 4b8e74c6af
3 changed files with 46 additions and 41 deletions
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4
src/Radio/antenna.cxx
View file

@ -54,7 +54,7 @@ double FGRadioAntenna::calculate_gain(double bearing, double angle) {
azimuth += azimuth % 2; azimuth += azimuth % 2;
int elevation = (int)floor(angle); int elevation = (int)floor(angle);
elevation += elevation % 2; elevation += elevation % 2;
cerr << "Bearing: " << bearing << " angle: " << angle << " azimuth: " << azimuth << " elevation: " << elevation << endl;
for (unsigned int i =0; i < _pattern.size(); i++) { for (unsigned int i =0; i < _pattern.size(); i++) {
AntennaGain point_gain = _pattern[i]; AntennaGain point_gain = _pattern[i];
@ -68,7 +68,7 @@ double FGRadioAntenna::calculate_gain(double bearing, double angle) {
/*** load external plot file generated by NEC4 /*** load external plot file generated by NEC2
***/ ***/
void FGRadioAntenna::load_antenna_pattern(string type) { void FGRadioAntenna::load_antenna_pattern(string type) {

74
src/Radio/radio.cxx
View file

@ -54,7 +54,7 @@ FGRadioTransmission::FGRadioTransmission() {
_rx_antenna_height = 2.0; // RX antenna height above ground level _rx_antenna_height = 2.0; // RX antenna height above ground level
_rx_antenna_gain = 1.0; // gain expressed in dBi _rx_antenna_gain = 1.0; // maximum antenna gain expressed in dBi
_tx_antenna_gain = 1.0; _tx_antenna_gain = 1.0;
_rx_line_losses = 2.0; // to be configured for each station _rx_line_losses = 2.0; // to be configured for each station
@ -277,7 +277,7 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
int max_points = (int)floor(distance_m / point_distance); int max_points = (int)floor(distance_m / point_distance);
double delta_last = fmod(distance_m, point_distance); double delta_last = fmod(distance_m, point_distance);
deque<double> _elevations; deque<double> elevations;
deque<string> materials; deque<string> materials;
@ -308,7 +308,7 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
unsigned int e_size = (deque<unsigned>::size_type)max_points; unsigned int e_size = (deque<unsigned>::size_type)max_points;
while (_elevations.size() <= e_size) { while (elevations.size() <= e_size) {
probe_distance += point_distance; probe_distance += point_distance;
SGGeod probe = SGGeod::fromGeoc(center.advanceRadM( course, probe_distance )); SGGeod probe = SGGeod::fromGeoc(center.advanceRadM( course, probe_distance ));
const SGMaterial *mat = 0; const SGMaterial *mat = 0;
@ -316,7 +316,7 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
if (scenery->get_elevation_m( probe, elevation_m, &mat )) { if (scenery->get_elevation_m( probe, elevation_m, &mat )) {
if((transmission_type == 3) || (transmission_type == 4)) { if((transmission_type == 3) || (transmission_type == 4)) {
_elevations.push_back(elevation_m); elevations.push_back(elevation_m);
if(mat) { if(mat) {
const std::vector<string> mat_names = mat->get_names(); const std::vector<string> mat_names = mat->get_names();
materials.push_back(mat_names[0]); materials.push_back(mat_names[0]);
@ -326,7 +326,7 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
} }
} }
else { else {
_elevations.push_front(elevation_m); elevations.push_front(elevation_m);
if(mat) { if(mat) {
const std::vector<string> mat_names = mat->get_names(); const std::vector<string> mat_names = mat->get_names();
materials.push_front(mat_names[0]); materials.push_front(mat_names[0]);
@ -338,36 +338,36 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
} }
else { else {
if((transmission_type == 3) || (transmission_type == 4)) { if((transmission_type == 3) || (transmission_type == 4)) {
_elevations.push_back(0.0); elevations.push_back(0.0);
materials.push_back("None"); materials.push_back("None");
} }
else { else {
_elevations.push_front(0.0); elevations.push_front(0.0);
materials.push_front("None"); materials.push_front("None");
} }
} }
} }
if((transmission_type == 3) || (transmission_type == 4)) { if((transmission_type == 3) || (transmission_type == 4)) {
_elevations.push_front(elevation_under_pilot); elevations.push_front(elevation_under_pilot);
if (delta_last > (point_distance / 2) ) // only add last point if it's farther than half point_distance if (delta_last > (point_distance / 2) ) // only add last point if it's farther than half point_distance
_elevations.push_back(elevation_under_sender); elevations.push_back(elevation_under_sender);
} }
else { else {
_elevations.push_back(elevation_under_pilot); elevations.push_back(elevation_under_pilot);
if (delta_last > (point_distance / 2) ) if (delta_last > (point_distance / 2) )
_elevations.push_front(elevation_under_sender); elevations.push_front(elevation_under_sender);
} }
double num_points= (double)_elevations.size(); double num_points= (double)elevations.size();
_elevations.push_front(point_distance); elevations.push_front(point_distance);
_elevations.push_front(num_points -1); elevations.push_front(num_points -1);
int size = _elevations.size(); int size = elevations.size();
double itm_elev[size]; double itm_elev[size];
for(int i=0;i<size;i++) { for(int i=0;i<size;i++) {
itm_elev[i]=_elevations[i]; itm_elev[i]=elevations[i];
//cerr << "ITM:: itm_elev: " << _elevations[i] << endl; //cerr << "ITM:: itm_elev: " << elevations[i] << endl;
} }
if((transmission_type == 3) || (transmission_type == 4)) { if((transmission_type == 3) || (transmission_type == 4)) {
@ -398,34 +398,40 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
_root_node->setStringValue("station[0]/prop-mode", strmode); _root_node->setStringValue("station[0]/prop-mode", strmode);
_root_node->setDoubleValue("station[0]/clutter-attenuation", clutter_loss); _root_node->setDoubleValue("station[0]/clutter-attenuation", clutter_loss);
_root_node->setDoubleValue("station[0]/polarization-attenuation", pol_loss); _root_node->setDoubleValue("station[0]/polarization-attenuation", pol_loss);
//cerr << "Clutter loss: " << clutter_loss << endl;
//if (errnum == 4) // if parameters are outside sane values for lrprop, the alternative method is used //if (errnum == 4) // if parameters are outside sane values for lrprop, the alternative method is used
// return -1; // return -1;
double tx_pattern_gain = 0.0;
double rx_pattern_gain = 0.0;
if (_root_node->getBoolValue("use-antenna-pattern", false)) {
double sender_heading = 270.0; // due West double sender_heading = 270.0; // due West
double tx_antenna_bearing = sender_heading - reverse_course; double tx_antenna_bearing = sender_heading - reverse_course * SGD_RADIANS_TO_DEGREES;
double rx_antenna_bearing = own_heading - course; double rx_antenna_bearing = own_heading - course * SGD_RADIANS_TO_DEGREES;
double rx_elev_angle = atan((itm_elev[2] + transmitter_height - itm_elev[(int)itm_elev[0] + 2] + receiver_height) / distance_m) * SGD_RADIANS_TO_DEGREES; double rx_elev_angle = atan((itm_elev[2] + transmitter_height - itm_elev[(int)itm_elev[0] + 2] + receiver_height) / distance_m) * SGD_RADIANS_TO_DEGREES;
double tx_elev_angle = 0.0 - rx_elev_angle; double tx_elev_angle = 0.0 - rx_elev_angle;
_TX_antenna = new FGRadioAntenna("Plot2"); FGRadioAntenna* TX_antenna;
_TX_antenna->set_heading(sender_heading); FGRadioAntenna* RX_antenna;
_TX_antenna->set_elevation_angle(0); TX_antenna = new FGRadioAntenna("Plot2");
double tx_pattern_gain = _TX_antenna->calculate_gain(tx_antenna_bearing, tx_elev_angle); TX_antenna->set_heading(sender_heading);
_RX_antenna = new FGRadioAntenna("Plot2"); TX_antenna->set_elevation_angle(0);
_RX_antenna->set_heading(own_heading); tx_pattern_gain = TX_antenna->calculate_gain(tx_antenna_bearing, tx_elev_angle);
_RX_antenna->set_elevation_angle(fgGetDouble("/orientation/pitch-deg")); RX_antenna = new FGRadioAntenna("Plot2");
double rx_pattern_gain = _RX_antenna->calculate_gain(rx_antenna_bearing, rx_elev_angle); RX_antenna->set_heading(own_heading);
RX_antenna->set_elevation_angle(fgGetDouble("/orientation/pitch-deg"));
rx_pattern_gain = RX_antenna->calculate_gain(rx_antenna_bearing, rx_elev_angle);
delete _TX_antenna; delete TX_antenna;
delete _RX_antenna; delete RX_antenna;
signal = link_budget - dbloss - clutter_loss + pol_loss; }
double signal_strength_dbm = signal_strength - dbloss - clutter_loss + pol_loss;
signal = link_budget - dbloss - clutter_loss + pol_loss + rx_pattern_gain + tx_pattern_gain;
double signal_strength_dbm = signal_strength - dbloss - clutter_loss + pol_loss + rx_pattern_gain + tx_pattern_gain;
double field_strength_uV = dbm_to_microvolt(signal_strength_dbm); double field_strength_uV = dbm_to_microvolt(signal_strength_dbm);
_root_node->setDoubleValue("station[0]/signal-dbm", signal_strength_dbm); _root_node->setDoubleValue("station[0]/signal-dbm", signal_strength_dbm);
_root_node->setDoubleValue("station[0]/field-strength-uV", field_strength_uV); _root_node->setDoubleValue("station[0]/field-strength-uV", field_strength_uV);
_root_node->setDoubleValue("station[0]/signal", signal); _root_node->setDoubleValue("station[0]/signal", signal);
_root_node->setDoubleValue("station[0]/tx-erp", tx_erp); _root_node->setDoubleValue("station[0]/tx-erp", tx_erp);
_root_node->setDoubleValue("station[0]/tx-pattern-gain", tx_pattern_gain); //_root_node->setDoubleValue("station[0]/tx-pattern-gain", tx_pattern_gain);
_root_node->setDoubleValue("station[0]/rx-pattern-gain", rx_pattern_gain); //_root_node->setDoubleValue("station[0]/rx-pattern-gain", rx_pattern_gain);
return signal; return signal;
} }

3
src/Radio/radio.hxx
View file

@ -48,8 +48,7 @@ private:
double _tx_antenna_gain; double _tx_antenna_gain;
double _rx_line_losses; double _rx_line_losses;
double _tx_line_losses; double _tx_line_losses;
FGRadioAntenna* _TX_antenna;
FGRadioAntenna* _RX_antenna;
double _terrain_sampling_distance; double _terrain_sampling_distance;
int _polarization; int _polarization;
std::map<string, double[2]> _mat_database; std::map<string, double[2]> _mat_database;