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commradio subsystem part deux

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This commit is contained in:
adrian 2011-09-16 16:28:16 +03:00
parent f96123de1c
commit 66e2bac574
2 changed files with 45 additions and 14 deletions
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56
src/Instrumentation/commradio.cxx
View file

@ -45,7 +45,7 @@ FGCommRadio::FGCommRadio(SGPropertyNode *node) {
//pilot plane's antenna gain + AI aircraft antenna gain
//real-life gain for conventional monopole/dipole antenna
_antenna_gain = 2.0;
_propagation_model = 2; // in the future choose between models via option: realistic radio on/off
_propagation_model = 2; // choose between models via option: realistic radio on/off
}
@ -65,6 +65,9 @@ void FGCommRadio::bind ()
void FGCommRadio::update ()
{
if (dt <= 0.0) {
return; // paused
}
}
double FGCommRadio::getFrequency(int radio) {
@ -86,7 +89,7 @@ double FGCommRadio::getFrequency(int radio) {
void FGCommRadio::receive(SGGeod tx_pos, double freq, string text,
void FGCommRadio::receive_text(SGGeod tx_pos, double freq, string text,
int ground_to_air) {
comm1 = getFrequency(1);
@ -105,6 +108,7 @@ void FGCommRadio::receive(SGGeod tx_pos, double freq, string text,
//and the signal, due to being amplitude modulated, decreases volume after demodulation
//the implementation below is more akin to what would happen on a FM transmission
//therefore the correct way would be to work on the volume
/*
string hash_noise = " ";
int reps = fabs((int)signal - 11);
int t_size = text.size();
@ -112,6 +116,7 @@ void FGCommRadio::receive(SGGeod tx_pos, double freq, string text,
int pos = rand() % t_size -1;
text.replace(pos,1, hash_noise);
}
*/
}
fgSetString("/sim/messages/atc", text.c_str());
@ -120,7 +125,7 @@ void FGCommRadio::receive(SGGeod tx_pos, double freq, string text,
}
double FGCommRadio::ITM_calculate_attenuation(SGGeod pos, double freq,
int ground_to_air) {
int transmission_type) {
/// Implement radio attenuation
/// based on the Longley-Rice propagation model
@ -146,10 +151,10 @@ double FGCommRadio::ITM_calculate_attenuation(SGGeod pos, double freq,
double tx_pow,ant_gain;
double signal = 0.0;
if(ground_to_air)
if(transmission_type == 1)
tx_pow = _transmitter_power + 6.0;
if(ground_to_air)
if((transmission_type == 1) || (transmission_type == 3))
ant_gain = _antenna_gain + 3.0; //pilot plane's antenna gain + ground station antenna gain
double link_budget = tx_pow - _receiver_sensitivity + ant_gain;
@ -215,7 +220,7 @@ double FGCommRadio::ITM_calculate_attenuation(SGGeod pos, double freq,
transmitter_height = sender_alt;
}
if(ground_to_air)
if(transmission_type == 1)
transmitter_height += ATC_HAAT;
else
transmitter_height += Aircraft_HAAT;
@ -231,15 +236,31 @@ double FGCommRadio::ITM_calculate_attenuation(SGGeod pos, double freq,
double elevation_m = 0.0;
if (scenery->get_elevation_m( probe, elevation_m, NULL )) {
_elevations.push_front(elevation_m);
//cerr << "ITM:: Probe elev: " << elevation_m << endl;
if((transmission_type == 3) || (transmission_type == 4)) {
_elevations.push_back(elevation_m);
}
else {
_elevations.push_front(elevation_m);
}
}
else {
if((transmission_type == 3) || (transmission_type == 4)) {
_elevations.push_back(elevation_m);
}
else {
_elevations.push_front(0.0);
}
}
}
_elevations.push_back(elevation_under_pilot);
_elevations.push_front(elevation_under_sender);
if((transmission_type == 3) || (transmission_type == 4)) {
_elevations.push_front(elevation_under_pilot);
_elevations.push_back(elevation_under_sender);
}
else {
_elevations.push_back(elevation_under_pilot);
_elevations.push_front(elevation_under_sender);
}
double max_alt_between=0.0;
for( deque<double>::size_type i = 0; i < _elevations.size(); i++ ) {
@ -267,10 +288,19 @@ double FGCommRadio::ITM_calculate_attenuation(SGGeod pos, double freq,
// TODO: If we clear the first Fresnel zone, we are into line of sight teritory
// else we need to calculate point to point link loss
if((transmission_type == 3) || (transmission_type == 4)) {
// the sender and receiver roles are switched
point_to_point(itm_elev, receiver_height, transmitter_height,
eps_dielect, sgm_conductivity, eno, frq_mhz, radio_climate,
pol, conf, rel, dbloss, strmode, errnum);
}
else {
point_to_point(itm_elev, transmitter_height, receiver_height,
eps_dielect, sgm_conductivity, eno, frq_mhz, radio_climate,
pol, conf, rel, dbloss, strmode, errnum);
point_to_point(itm_elev, transmitter_height, receiver_height,
eps_dielect, sgm_conductivity, eno, frq_mhz, radio_climate,
pol, conf, rel, dbloss, strmode, errnum);
}
cerr << "ITM:: Link budget: " << link_budget << ", Attenuation: " << dbloss << " dBm, " << strmode << ", Error: " << errnum << endl;

3
src/Instrumentation/commradio.hxx
View file

@ -61,7 +61,8 @@ public:
void setFrequency(double freq, int radio);
double getFrequency(int radio);
void setTxPower(double txpower) { _transmitter_power = txpower; };
void receive_text(SGGeod tx_pos, double freq, string text, int ground_to_air);
// transmission_type: 1 for ground to air, 2 for air to air, 3 for pilot to ground, 4 for pilot to air
void receive_text(SGGeod tx_pos, double freq, string text, int transmission_type);
void setPropagationModel(int model) { _propagation_model = model; };
};