// radio.cxx -- implementation of FGRadio
// Class to manage radio propagation using the ITM model
-// Written by Adrian Musceac, started August 2011.
+// Written by Adrian Musceac YO8RZZ, started August 2011.
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
#include "radio.hxx"
#include <simgear/scene/material/mat.hxx>
#include <Scenery/scenery.hxx>
+#include <boost/scoped_array.hpp>
#define WITH_POINT_TO_POINT 1
#include "itm.cpp"
FGRadioTransmission::FGRadioTransmission() {
- _receiver_sensitivity = -105.0; // typical AM receiver sensitivity seems to be 0.8 microVolt at 12dB SINAD
+ _receiver_sensitivity = -105.0; // typical AM receiver sensitivity seems to be 0.8 microVolt at 12dB SINAD or less
/** AM transmitter power in dBm.
* Typical output powers for ATC ground equipment, VHF-UHF:
return freq;
}
-/*** TODO: receive multiplayer chat message and voice
-***/
+
void FGRadioTransmission::receiveChat(SGGeod tx_pos, double freq, string text, int ground_to_air) {
}
-/*** TODO: receive navaid
-***/
+
double FGRadioTransmission::receiveNav(SGGeod tx_pos, double freq, int transmission_type) {
- // typical VOR/LOC transmitter power appears to be 200 Watt ~ 53 dBm
+ // typical VOR/LOC transmitter power appears to be 100 - 200 Watt i.e 50 - 53 dBm
// vor/loc typical sensitivity between -107 and -101 dBm
// glideslope sensitivity between -85 and -81 dBm
if ( _propagation_model == 1) {
}
-/*** Receive ATC radio communication as text
-***/
-void FGRadioTransmission::receiveATC(SGGeod tx_pos, double freq, string text, int ground_to_air) {
+double FGRadioTransmission::receiveBeacon(SGGeod &tx_pos, double heading, double pitch) {
+
+ // these properties should be set by an instrument
+ _receiver_sensitivity = _root_node->getDoubleValue("station[0]/rx-sensitivity", _receiver_sensitivity);
+ _transmitter_power = watt_to_dbm(_root_node->getDoubleValue("station[0]/tx-power-watt", _transmitter_power));
+ _polarization = _root_node->getIntValue("station[0]/polarization", 1);
+ _tx_antenna_height += _root_node->getDoubleValue("station[0]/tx-antenna-height", 0);
+ _rx_antenna_height += _root_node->getDoubleValue("station[0]/rx-antenna-height", 0);
+ _tx_antenna_gain += _root_node->getDoubleValue("station[0]/tx-antenna-gain", 0);
+ _rx_antenna_gain += _root_node->getDoubleValue("station[0]/rx-antenna-gain", 0);
+
+ double freq = _root_node->getDoubleValue("station[0]/frequency", 144.8); // by default stay in the ham 2 meter band
+
+ double comm1 = getFrequency(1);
+ double comm2 = getFrequency(2);
+ if ( !(fabs(freq - comm1) <= 0.0001) && !(fabs(freq - comm2) <= 0.0001) ) {
+ return -1;
+ }
+ double signal = ITM_calculate_attenuation(tx_pos, freq, 1);
+
+ return signal;
+}
+
+
+
+void FGRadioTransmission::receiveATC(SGGeod tx_pos, double freq, string text, int ground_to_air) {
+
+ // adjust some default parameters in case the ATC code does not set them
if(ground_to_air == 1) {
_transmitter_power += 4.0;
_tx_antenna_height += 30.0;
_tx_antenna_gain += 2.0;
}
-
double comm1 = getFrequency(1);
double comm2 = getFrequency(2);
if ( !(fabs(freq - comm1) <= 0.0001) && !(fabs(freq - comm2) <= 0.0001) ) {
}
else {
- if ( _propagation_model == 0) {
- // skip propagation routines entirely
+ if ( _propagation_model == 0) { // skip propagation routines entirely
fgSetString("/sim/messages/atc", text.c_str());
}
- else if ( _propagation_model == 1 ) {
- // Use free-space, round earth
+ else if ( _propagation_model == 1 ) { // Use free-space, round earth
+
double signal = LOS_calculate_attenuation(tx_pos, freq, ground_to_air);
if (signal <= 0.0) {
return;
}
else {
-
fgSetString("/sim/messages/atc", text.c_str());
-
}
}
- else if ( _propagation_model == 2 ) {
- // Use ITM propagation model
+ else if ( _propagation_model == 2 ) { // Use ITM propagation model
+
double signal = ITM_calculate_attenuation(tx_pos, freq, ground_to_air);
if (signal <= 0.0) {
return;
}
if ((signal > 0.0) && (signal < 12.0)) {
- /** for low SNR values implement a way to make the conversation
+ /** for low SNR values need a way to make the conversation
* hard to understand but audible
* in the real world, the receiver AGC fails to capture the slope
* and the signal, due to being amplitude modulated, decreases volume after demodulation
text.replace(pos,1, hash_noise);
}
*/
- double volume = (fabs(signal - 12.0) / 12);
- double old_volume = fgGetDouble("/sim/sound/voices/voice/volume");
- SG_LOG(SG_GENERAL, SG_BULK, "Usable signal at limit: " << signal);
- //cerr << "Usable signal at limit: " << signal << endl;
- fgSetDouble("/sim/sound/voices/voice/volume", volume);
+ //double volume = (fabs(signal - 12.0) / 12);
+ //double old_volume = fgGetDouble("/sim/sound/voices/voice/volume");
+
+ //fgSetDouble("/sim/sound/voices/voice/volume", volume);
fgSetString("/sim/messages/atc", text.c_str());
- fgSetDouble("/sim/sound/voices/voice/volume", old_volume);
+ //fgSetDouble("/sim/sound/voices/voice/volume", old_volume);
}
else {
fgSetString("/sim/messages/atc", text.c_str());
}
-
}
-
}
-
}
-/*** Implement radio attenuation
- based on the Longley-Rice propagation model
-***/
+
double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, int transmission_type) {
-
+ if((freq < 40.0) || (freq > 20000.0)) // frequency out of recommended range
+ return -1;
/** ITM default parameters
TODO: take them from tile materials (especially for sea)?
**/
double reverse_course = SGGeodesy::courseRad(sender_pos_c, own_pos_c);
double distance_m = SGGeodesy::distanceM(own_pos, sender_pos);
double probe_distance = 0.0;
- /** If distance larger than this value (300 km), assume reception imposssible */
+ /** If distance larger than this value (300 km), assume reception imposssible to spare CPU cycles */
if (distance_m > 300000)
return -1.0;
- /** If above 8000 meters, consider LOS mode and calculate free-space att */
+ /** If above 8000 meters, consider LOS mode and calculate free-space att to spare CPU cycles */
if (own_alt > 8000) {
dbloss = 20 * log10(distance_m) +20 * log10(frq_mhz) -27.55;
SG_LOG(SG_GENERAL, SG_BULK,
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<string> materials;
+ deque<string*> materials;
double elevation_under_pilot = 0.0;
transmitter_height += _tx_antenna_height;
receiver_height += _rx_antenna_height;
-
- SG_LOG(SG_GENERAL, SG_BULK,
- "ITM:: RX-height: " << receiver_height << " meters, TX-height: " << transmitter_height << " meters, Distance: " << distance_m << " meters");
//cerr << "ITM:: RX-height: " << receiver_height << " meters, TX-height: " << transmitter_height << " meters, Distance: " << distance_m << " meters" << endl;
_root_node->setDoubleValue("station[0]/rx-height", receiver_height);
_root_node->setDoubleValue("station[0]/tx-height", transmitter_height);
elevations.push_back(elevation_m);
if(mat) {
const std::vector<string> mat_names = mat->get_names();
- materials.push_back(mat_names[0]);
+ string* name = new string(mat_names[0]);
+ materials.push_back(name);
}
else {
- materials.push_back("None");
+ string* no_material = new string("None");
+ materials.push_back(no_material);
}
}
else {
elevations.push_front(elevation_m);
if(mat) {
const std::vector<string> mat_names = mat->get_names();
- materials.push_front(mat_names[0]);
+ string* name = new string(mat_names[0]);
+ materials.push_front(name);
}
else {
- materials.push_front("None");
+ string* no_material = new string("None");
+ materials.push_front(no_material);
}
}
}
else {
if((transmission_type == 3) || (transmission_type == 4)) {
elevations.push_back(0.0);
- materials.push_back("None");
+ string* no_material = new string("None");
+ materials.push_back(no_material);
}
else {
+ string* no_material = new string("None");
elevations.push_front(0.0);
- materials.push_front("None");
+ materials.push_front(no_material);
}
}
}
if((transmission_type == 3) || (transmission_type == 4)) {
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);
}
else {
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(num_points -1);
int size = elevations.size();
- double *itm_elev;
- itm_elev = new double[size];
+ boost::scoped_array<double> itm_elev( new double[size] );
for(int i=0;i<size;i++) {
itm_elev[i]=elevations[i];
-
-
}
if((transmission_type == 3) || (transmission_type == 4)) {
// the sender and receiver roles are switched
- point_to_point(itm_elev, receiver_height, transmitter_height,
+ ITM::point_to_point(itm_elev.get(), receiver_height, transmitter_height,
eps_dielect, sgm_conductivity, eno, frq_mhz, radio_climate,
pol, conf, rel, dbloss, strmode, p_mode, horizons, errnum);
if( _root_node->getBoolValue( "use-clutter-attenuation", false ) )
- calculate_clutter_loss(frq_mhz, itm_elev, materials, receiver_height, transmitter_height, p_mode, horizons, clutter_loss);
+ calculate_clutter_loss(frq_mhz, itm_elev.get(), materials, receiver_height, transmitter_height, p_mode, horizons, clutter_loss);
}
else {
- point_to_point(itm_elev, transmitter_height, receiver_height,
+ ITM::point_to_point(itm_elev.get(), transmitter_height, receiver_height,
eps_dielect, sgm_conductivity, eno, frq_mhz, radio_climate,
pol, conf, rel, dbloss, strmode, p_mode, horizons, errnum);
if( _root_node->getBoolValue( "use-clutter-attenuation", false ) )
- calculate_clutter_loss(frq_mhz, itm_elev, materials, transmitter_height, receiver_height, p_mode, horizons, clutter_loss);
+ calculate_clutter_loss(frq_mhz, itm_elev.get(), materials, transmitter_height, receiver_height, p_mode, horizons, clutter_loss);
}
double pol_loss = 0.0;
+ // TODO: remove this check after we check a bit the axis calculations in this function
if (_polarization == 1) {
pol_loss = polarization_loss();
}
- SG_LOG(SG_GENERAL, SG_BULK,
- "ITM:: Link budget: " << link_budget << ", Attenuation: " << dbloss << " dBm, " << strmode << ", Error: " << errnum);
+ //SG_LOG(SG_GENERAL, SG_BULK,
+ // "ITM:: Link budget: " << link_budget << ", Attenuation: " << dbloss << " dBm, " << strmode << ", Error: " << errnum);
//cerr << "ITM:: Link budget: " << link_budget << ", Attenuation: " << dbloss << " dBm, " << strmode << ", Error: " << errnum << endl;
_root_node->setDoubleValue("station[0]/link-budget", link_budget);
_root_node->setDoubleValue("station[0]/terrain-attenuation", dbloss);
_root_node->setStringValue("station[0]/prop-mode", strmode);
_root_node->setDoubleValue("station[0]/clutter-attenuation", clutter_loss);
_root_node->setDoubleValue("station[0]/polarization-attenuation", pol_loss);
- //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, bail out fast
// return -1;
+
+ // temporary, keep this antenna radiation pattern code here
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 tx_antenna_bearing = sender_heading - reverse_course * SGD_RADIANS_TO_DEGREES;
- 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 tx_elev_angle = 0.0 - rx_elev_angle;
+ double sender_heading = 270.0; // due West
+ double tx_antenna_bearing = sender_heading - reverse_course * SGD_RADIANS_TO_DEGREES;
+ 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 tx_elev_angle = 0.0 - rx_elev_angle;
+ if (_root_node->getBoolValue("use-tx-antenna-pattern", false)) {
FGRadioAntenna* TX_antenna;
- FGRadioAntenna* RX_antenna;
TX_antenna = new FGRadioAntenna("Plot2");
TX_antenna->set_heading(sender_heading);
TX_antenna->set_elevation_angle(0);
tx_pattern_gain = TX_antenna->calculate_gain(tx_antenna_bearing, tx_elev_angle);
+ delete TX_antenna;
+ }
+ if (_root_node->getBoolValue("use-rx-antenna-pattern", false)) {
+ FGRadioAntenna* RX_antenna;
RX_antenna = new FGRadioAntenna("Plot2");
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 RX_antenna;
}
//_root_node->setDoubleValue("station[0]/tx-pattern-gain", tx_pattern_gain);
//_root_node->setDoubleValue("station[0]/rx-pattern-gain", rx_pattern_gain);
- delete[] itm_elev;
-
+ for (unsigned i =0; i < materials.size(); i++) {
+ delete materials[i];
+ }
+
return signal;
}
-/*** Calculate losses due to vegetation and urban clutter (WIP)
-* We are only worried about clutter loss, terrain influence
-* on the first Fresnel zone is calculated in the ITM functions
-***/
-void FGRadioTransmission::calculate_clutter_loss(double freq, double itm_elev[], deque<string> &materials,
+
+void FGRadioTransmission::calculate_clutter_loss(double freq, double itm_elev[], deque<string*> &materials,
double transmitter_height, double receiver_height, int p_mode,
double horizons[], double &clutter_loss) {
double distance_m = itm_elev[0] * itm_elev[1]; // only consider elevation points
-
+ unsigned mat_size = materials.size();
if (p_mode == 0) { // LOS: take each point and see how clutter height affects first Fresnel zone
int mat = 0;
int j=1;
double clutter_height = 0.0; // mean clutter height for a certain terrain type
double clutter_density = 0.0; // percent of reflected wave
+ if((unsigned)mat >= mat_size) { //this tends to happen when the model interferes with the antenna (obstructs)
+ //cerr << "Array index out of bounds 0-0: " << mat << " size: " << mat_size << endl;
+ break;
+ }
get_material_properties(materials[mat], clutter_height, clutter_density);
double grad = fabs(itm_elev[2] + transmitter_height - itm_elev[(int)itm_elev[0] + 2] + receiver_height) / distance_m;
// First Fresnel radius
double frs_rad = 548 * sqrt( (j * itm_elev[1] * (itm_elev[0] - j) * itm_elev[1] / 1000000) / ( distance_m * freq / 1000) );
-
+ if (frs_rad <= 0.0) { //this tends to happen when the model interferes with the antenna (obstructs)
+ //cerr << "Frs rad 0-0: " << frs_rad << endl;
+ continue;
+ }
//double earth_h = distance_m * (distance_m - j * itm_elev[1]) / ( 1000000 * 12.75 * 1.33 ); // K=4/3
double min_elev = SGMiscd::min(itm_elev[2] + transmitter_height, itm_elev[(int)itm_elev[0] + 2] + receiver_height);
break;
double clutter_height = 0.0; // mean clutter height for a certain terrain type
double clutter_density = 0.0; // percent of reflected wave
+
+ if((unsigned)mat >= mat_size) {
+ //cerr << "Array index out of bounds 1-1: " << mat << " size: " << mat_size << endl;
+ break;
+ }
get_material_properties(materials[mat], clutter_height, clutter_density);
double grad = fabs(itm_elev[2] + transmitter_height - itm_elev[num_points_1st + 2] + clutter_height) / distance_m;
// First Fresnel radius
double frs_rad = 548 * sqrt( (j * itm_elev[1] * (num_points_1st - j) * itm_elev[1] / 1000000) / ( num_points_1st * itm_elev[1] * freq / 1000) );
-
+ if (frs_rad <= 0.0) {
+ //cerr << "Frs rad 1-1: " << frs_rad << endl;
+ continue;
+ }
//double earth_h = distance_m * (distance_m - j * itm_elev[1]) / ( 1000000 * 12.75 * 1.33 ); // K=4/3
double min_elev = SGMiscd::min(itm_elev[2] + transmitter_height, itm_elev[num_points_1st + 2] + clutter_height);
break;
double clutter_height = 0.0; // mean clutter height for a certain terrain type
double clutter_density = 0.0; // percent of reflected wave
+
+ if((unsigned)mat >= mat_size) {
+ //cerr << "Array index out of bounds 1-2: " << mat << " size: " << mat_size << endl;
+ break;
+ }
get_material_properties(materials[mat], clutter_height, clutter_density);
double grad = fabs(itm_elev[last+1] + clutter_height - itm_elev[(int)itm_elev[0] + 2] + receiver_height) / distance_m;
// First Fresnel radius
double frs_rad = 548 * sqrt( (j * itm_elev[1] * (num_points_2nd - j) * itm_elev[1] / 1000000) / ( num_points_2nd * itm_elev[1] * freq / 1000) );
-
+ if (frs_rad <= 0.0) {
+ //cerr << "Frs rad 1-2: " << frs_rad << " numpoints2 " << num_points_2nd << " j: " << j << endl;
+ continue;
+ }
//double earth_h = distance_m * (distance_m - j * itm_elev[1]) / ( 1000000 * 12.75 * 1.33 ); // K=4/3
double min_elev = SGMiscd::min(itm_elev[last+1] + clutter_height, itm_elev[(int)itm_elev[0] + 2] + receiver_height);
break;
double clutter_height = 0.0; // mean clutter height for a certain terrain type
double clutter_density = 0.0; // percent of reflected wave
+ if((unsigned)mat >= mat_size) {
+ //cerr << "Array index out of bounds 2-1: " << mat << " size: " << mat_size << endl;
+ break;
+ }
get_material_properties(materials[mat], clutter_height, clutter_density);
double grad = fabs(itm_elev[2] + transmitter_height - itm_elev[num_points_1st + 2] + clutter_height) / distance_m;
// First Fresnel radius
double frs_rad = 548 * sqrt( (j * itm_elev[1] * (num_points_1st - j) * itm_elev[1] / 1000000) / ( num_points_1st * itm_elev[1] * freq / 1000) );
-
+ if (frs_rad <= 0.0) {
+ //cerr << "Frs rad 2-1: " << frs_rad << " numpoints1 " << num_points_1st << " j: " << j << endl;
+ continue;
+ }
//double earth_h = distance_m * (distance_m - j * itm_elev[1]) / ( 1000000 * 12.75 * 1.33 ); // K=4/3
double min_elev = SGMiscd::min(itm_elev[2] + transmitter_height, itm_elev[num_points_1st + 2] + clutter_height);
// no losses
}
j++;
+ mat++;
last = k;
}
mat +=1;
break;
double clutter_height = 0.0; // mean clutter height for a certain terrain type
double clutter_density = 0.0; // percent of reflected wave
+ if((unsigned)mat >= mat_size) {
+ //cerr << "Array index out of bounds 2-2: " << mat << " size: " << mat_size << endl;
+ break;
+ }
get_material_properties(materials[mat], clutter_height, clutter_density);
double grad = fabs(itm_elev[last+1] + clutter_height - itm_elev[num_points_1st + num_points_2nd + 2] + clutter_height) / distance_m;
// First Fresnel radius
double frs_rad = 548 * sqrt( (j * itm_elev[1] * (num_points_2nd - j) * itm_elev[1] / 1000000) / ( num_points_2nd * itm_elev[1] * freq / 1000) );
-
+ if (frs_rad <= 0.0) {
+ //cerr << "Frs rad 2-2: " << frs_rad << " numpoints2 " << num_points_2nd << " j: " << j << endl;
+ continue;
+ }
//double earth_h = distance_m * (distance_m - j * itm_elev[1]) / ( 1000000 * 12.75 * 1.33 ); // K=4/3
double min_elev = SGMiscd::min(itm_elev[last+1] + clutter_height, itm_elev[num_points_1st + num_points_2nd +2] + clutter_height);
break;
double clutter_height = 0.0; // mean clutter height for a certain terrain type
double clutter_density = 0.0; // percent of reflected wave
+ if((unsigned)mat >= mat_size) {
+ //cerr << "Array index out of bounds 2-3: " << mat << " size: " << mat_size << endl;
+ break;
+ }
get_material_properties(materials[mat], clutter_height, clutter_density);
double grad = fabs(itm_elev[last2+1] + clutter_height - itm_elev[(int)itm_elev[0] + 2] + receiver_height) / distance_m;
// First Fresnel radius
double frs_rad = 548 * sqrt( (j * itm_elev[1] * (num_points_3rd - j) * itm_elev[1] / 1000000) / ( num_points_3rd * itm_elev[1] * freq / 1000) );
-
+ if (frs_rad <= 0.0) {
+ //cerr << "Frs rad 2-3: " << frs_rad << " numpoints3 " << num_points_3rd << " j: " << j << endl;
+ continue;
+ }
//double earth_h = distance_m * (distance_m - j * itm_elev[1]) / ( 1000000 * 12.75 * 1.33 ); // K=4/3
}
}
- else if (p_mode == 2) { // troposcatter: ignore ground clutter for now...
+ else if (p_mode == 2) { // troposcatter: ignore ground clutter for now... maybe do something with weather
clutter_loss = 0.0;
}
}
-/*** Temporary material properties database
-* height: median clutter height
-* density: radiowave attenuation factor
-***/
-void FGRadioTransmission::get_material_properties(string mat_name, double &height, double &density) {
+
+void FGRadioTransmission::get_material_properties(string* mat_name, double &height, double &density) {
- if(mat_name == "Landmass") {
+ if(!mat_name)
+ return;
+
+ if(*mat_name == "Landmass") {
height = 15.0;
density = 0.2;
}
- else if(mat_name == "SomeSort") {
+ else if(*mat_name == "SomeSort") {
height = 15.0;
density = 0.2;
}
- else if(mat_name == "Island") {
+ else if(*mat_name == "Island") {
height = 15.0;
density = 0.2;
}
- else if(mat_name == "Default") {
+ else if(*mat_name == "Default") {
height = 15.0;
density = 0.2;
}
- else if(mat_name == "EvergreenBroadCover") {
+ else if(*mat_name == "EvergreenBroadCover") {
height = 20.0;
density = 0.2;
}
- else if(mat_name == "EvergreenForest") {
+ else if(*mat_name == "EvergreenForest") {
height = 20.0;
density = 0.2;
}
- else if(mat_name == "DeciduousBroadCover") {
+ else if(*mat_name == "DeciduousBroadCover") {
height = 15.0;
density = 0.3;
}
- else if(mat_name == "DeciduousForest") {
+ else if(*mat_name == "DeciduousForest") {
height = 15.0;
density = 0.3;
}
- else if(mat_name == "MixedForestCover") {
+ else if(*mat_name == "MixedForestCover") {
height = 20.0;
density = 0.25;
}
- else if(mat_name == "MixedForest") {
+ else if(*mat_name == "MixedForest") {
height = 15.0;
density = 0.25;
}
- else if(mat_name == "RainForest") {
+ else if(*mat_name == "RainForest") {
height = 25.0;
density = 0.55;
}
- else if(mat_name == "EvergreenNeedleCover") {
+ else if(*mat_name == "EvergreenNeedleCover") {
height = 15.0;
density = 0.2;
}
- else if(mat_name == "WoodedTundraCover") {
+ else if(*mat_name == "WoodedTundraCover") {
height = 5.0;
density = 0.15;
}
- else if(mat_name == "DeciduousNeedleCover") {
+ else if(*mat_name == "DeciduousNeedleCover") {
height = 5.0;
density = 0.2;
}
- else if(mat_name == "ScrubCover") {
+ else if(*mat_name == "ScrubCover") {
height = 3.0;
density = 0.15;
}
- else if(mat_name == "BuiltUpCover") {
+ else if(*mat_name == "BuiltUpCover") {
height = 30.0;
density = 0.7;
}
- else if(mat_name == "Urban") {
+ else if(*mat_name == "Urban") {
height = 30.0;
density = 0.7;
}
- else if(mat_name == "Construction") {
+ else if(*mat_name == "Construction") {
height = 30.0;
density = 0.7;
}
- else if(mat_name == "Industrial") {
+ else if(*mat_name == "Industrial") {
height = 30.0;
density = 0.7;
}
- else if(mat_name == "Port") {
+ else if(*mat_name == "Port") {
height = 30.0;
density = 0.7;
}
- else if(mat_name == "Town") {
+ else if(*mat_name == "Town") {
height = 10.0;
density = 0.5;
}
- else if(mat_name == "SubUrban") {
+ else if(*mat_name == "SubUrban") {
height = 10.0;
density = 0.5;
}
- else if(mat_name == "CropWoodCover") {
+ else if(*mat_name == "CropWoodCover") {
height = 10.0;
density = 0.1;
}
- else if(mat_name == "CropWood") {
+ else if(*mat_name == "CropWood") {
height = 10.0;
density = 0.1;
}
- else if(mat_name == "AgroForest") {
+ else if(*mat_name == "AgroForest") {
height = 10.0;
density = 0.1;
}
}
-/*** implement simple LOS propagation model (WIP)
-***/
+
double FGRadioTransmission::LOS_calculate_attenuation(SGGeod pos, double freq, int transmission_type) {
- double frq_mhz;
- if( (freq < 118.0) || (freq > 137.0) )
- frq_mhz = 125.0; // sane value, middle of bandplan
- else
- frq_mhz = freq;
+
+ double frq_mhz = freq;
double dbloss;
double tx_pow = _transmitter_power;
double ant_gain = _rx_antenna_gain + _tx_antenna_gain;
// free-space loss (distance calculation should be changed)
dbloss = 20 * log10(distance_m) +20 * log10(frq_mhz) -27.55;
signal = link_budget - dbloss + pol_loss;
- SG_LOG(SG_GENERAL, SG_BULK,
- "LOS:: Link budget: " << link_budget << ", Attenuation: " << dbloss << " dBm ");
+
//cerr << "LOS:: Link budget: " << link_budget << ", Attenuation: " << dbloss << " dBm " << endl;
return signal;
projects / flightgear.git / blobdiff