Added ftm attributes to WiFiMeasurement

sensors/radio/WiFiMeasurement.h

@@ -29,6 +29,18 @@ private:
 	/** the measured signal strength */
 	float rssi;
 
+    /** FTM: estimated distance in m **/
+    float distance = NAN;
+
+    /** FTM: standard deviation of estimated distance in m. Only valid if numSuccessfulMeasurements >= 2 **/
+    float distanceStdDev = NAN;
+
+    /** FTM: The number of attempted measurements used in the RTT exchange  **/
+    int numAttemptedMeasurements = 0;
+
+    /** FTM: The number of successful measurements used to calculate the distance and standard deviation **/
+    int numSuccessfulMeasurements = 0;
+    
 	/** OPTIONAL. frequence the signal was received */
 	float freq = NAN;
 
@@ -52,6 +64,12 @@ public:
 			;
 	}
 
+    /** ctor with timestamp and ftm */
+    WiFiMeasurement(const AccessPoint& ap, const float rssi, const Timestamp ts, const float distance, const float distanceStdDev, const int numAttemptedMeasurements, const int numSuccessfulMeasurements) 
+        : ap(ap), rssi(rssi), freq(NAN), ts(ts), distance(distance), distanceStdDev(distanceStdDev), numAttemptedMeasurements(numAttemptedMeasurements), numSuccessfulMeasurements(numSuccessfulMeasurements) {
+        ;
+    }
+
 	/** ctor with timestamp and freq*/
 	WiFiMeasurement(const AccessPoint& ap, const float rssi, const float freq, const Timestamp ts) : ap(ap), rssi(rssi), freq(freq), ts(ts) {
 			;
@@ -68,6 +86,12 @@ public:
 	/** OPTIONAL: get the measurement's timestamp (if known!) */
 	const Timestamp& getTimestamp() const {return ts;}
 
+    float getFtmDist() const { return distance; }
+    float getFtmDistStd() const { return distanceStdDev; }
+
+    int getNumAttemptedMeasurements() const { return numAttemptedMeasurements; }
+    int getNumSuccessfulMeasurements() const { return numSuccessfulMeasurements; }
+
 	/** timestamp known? */
 	bool hasTimestamp() const {return ts == ts;}
 
@@ -83,6 +107,8 @@ public:
 	/** set the timestamp */
 	void setTimestamp(const Timestamp& val){ts = val;}
 
+    void setFtmDist(float val) { distance = val; }
+
 	/** as string for debug printing */
 	std::string asString() const {
 		std::string res = ap.asString();