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Rename conversion functions to be more explicit

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...and set some more properties: tx-erp, etc.
This commit is contained in:
adrian 2011-12-03 18:48:24 +02:00
parent e4f511fb31
commit 52bdb959c7
2 changed files with 11 additions and 15 deletions
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22
src/Radio/radio.cxx
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@ -145,10 +145,7 @@ void FGRadioTransmission::receiveATC(SGGeod tx_pos, double freq, string text, in
else { else {
fgSetString("/sim/messages/atc", text.c_str()); fgSetString("/sim/messages/atc", text.c_str());
/** write signal strength above threshold to the property tree
* to implement a simple S-meter just divide by 3 dB per grade (VHF norm)
**/
_root_node->setDoubleValue("station[0]/signal", signal);
} }
} }
else if ( _propagation_model == 2 ) { else if ( _propagation_model == 2 ) {
@ -180,15 +177,10 @@ void FGRadioTransmission::receiveATC(SGGeod tx_pos, double freq, string text, in
//cerr << "Usable signal at limit: " << signal << endl; //cerr << "Usable signal at limit: " << signal << endl;
fgSetDouble("/sim/sound/voices/voice/volume", volume); fgSetDouble("/sim/sound/voices/voice/volume", volume);
fgSetString("/sim/messages/atc", text.c_str()); fgSetString("/sim/messages/atc", text.c_str());
_root_node->setDoubleValue("station[0]/signal", signal);
fgSetDouble("/sim/sound/voices/voice/volume", old_volume); fgSetDouble("/sim/sound/voices/voice/volume", old_volume);
} }
else { else {
fgSetString("/sim/messages/atc", text.c_str()); fgSetString("/sim/messages/atc", text.c_str());
/** write signal strength above threshold to the property tree
* to implement a simple S-meter just divide by 3 dB per grade (VHF norm)
**/
_root_node->setDoubleValue("station[0]/signal", signal);
} }
} }
@ -233,6 +225,8 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
double link_budget = tx_pow - _receiver_sensitivity - _rx_line_losses - _tx_line_losses + ant_gain; double link_budget = tx_pow - _receiver_sensitivity - _rx_line_losses - _tx_line_losses + ant_gain;
double signal_strength = tx_pow - _rx_line_losses - _tx_line_losses + ant_gain; double signal_strength = tx_pow - _rx_line_losses - _tx_line_losses + ant_gain;
double tx_erp = dbm_to_watt(tx_pow + _tx_antenna_gain - _tx_line_losses);
FGScenery * scenery = globals->get_scenery(); FGScenery * scenery = globals->get_scenery();
@ -309,7 +303,7 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
//cerr << "ITM:: RX-height: " << receiver_height << " meters, TX-height: " << transmitter_height << " meters, Distance: " << distance_m << " meters" << endl; //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]/rx-height", receiver_height);
_root_node->setDoubleValue("station[0]/tx-height", transmitter_height); _root_node->setDoubleValue("station[0]/tx-height", transmitter_height);
_root_node->setDoubleValue("station[0]/distance", distance_m); _root_node->setDoubleValue("station[0]/distance", distance_m / 1000);
unsigned int e_size = (deque<unsigned>::size_type)max_points; unsigned int e_size = (deque<unsigned>::size_type)max_points;
@ -411,6 +405,8 @@ double FGRadioTransmission::ITM_calculate_attenuation(SGGeod pos, double freq, i
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]/tx-erp", tx_erp);
return signal; return signal;
} }
@ -921,16 +917,16 @@ double FGRadioTransmission::polarization_loss() {
} }
double FGRadioTransmission::power_to_dbm(double power_watt) { double FGRadioTransmission::watt_to_dbm(double power_watt) {
return 10 * log10(1000 * power_watt); // returns dbm return 10 * log10(1000 * power_watt); // returns dbm
} }
double FGRadioTransmission::dbm_to_power(double dbm) { double FGRadioTransmission::dbm_to_watt(double dbm) {
return exp( (dbm-30) * log(10) / 10); // returns Watts return exp( (dbm-30) * log(10) / 10); // returns Watts
} }
double FGRadioTransmission::dbm_to_microvolt(double dbm) { double FGRadioTransmission::dbm_to_microvolt(double dbm) {
return sqrt(dbm_to_power(dbm) * 50) * 1000000; // returns microvolts return sqrt(dbm_to_watt(dbm) * 50) * 1000000; // returns microvolts
} }

4
src/Radio/radio.hxx
View file

@ -80,8 +80,8 @@ public:
void setPropagationModel(int model) { _propagation_model = model; }; void setPropagationModel(int model) { _propagation_model = model; };
void setPolarization(int polarization) { _polarization = polarization; }; void setPolarization(int polarization) { _polarization = polarization; };
// accessory functions for unit conversions // accessory functions for unit conversions
double power_to_dbm(double power_watt); double watt_to_dbm(double power_watt);
double dbm_to_power(double dbm); double dbm_to_watt(double dbm);
double dbm_to_microvolt(double dbm); double dbm_to_microvolt(double dbm);