public static Point Trilateration(PointData pd1, PointData pd2, PointData pd3)
{
Point pc1 = RoomData.GetCoordinates(pd1.id);
Point pc2 = RoomData.GetCoordinates(pd2.id);
Point pc3 = RoomData.GetCoordinates(pd3.id);
List <Point> results = new List <Point>();
double d1 = DistanceFromRssi(pd1);
double d2 = DistanceFromRssi(pd2);
double d3 = DistanceFromRssi(pd3);
GetCircleIntersections(results, pc1, pc2, d1, d2);
GetCircleIntersections(results, pc2, pc3, d2, d3);
GetCircleIntersections(results, pc1, pc3, d1, d3);
double minDistance = double.MaxValue;
Point bestPoint = null;
foreach (Point p1 in results)
{
foreach (Point p2 in results)
{
if (p1 != p2)
{
double distance = p1.Distance(p2);
if (distance < minDistance)
{
bestPoint = p1.Avg(p2);
distance = minDistance;
}
}
}
}
return(bestPoint);
}
public static List <PointData> ReadCSV(string pathToFile)
{
List <PointData> data = new List <PointData>();
using (StreamReader sr = new StreamReader(pathToFile))
{
sr.ReadLine();
while (sr.Peek() >= 0)
{
string line = sr.ReadLine();
PointData pd = new PointData();
string[] splitted = line.Split(',');
pd.id = Convert.ToInt32(splitted[3]);
pd.rssi = Convert.ToDouble(splitted[4].Replace('.', ','));
pd.timestamp = DateTime.ParseExact(splitted[5], "yyyy-MM-dd HH:mm:ss.fff", System.Globalization.CultureInfo.InvariantCulture);
data.Add(pd);
}
}
data.Sort((pd1, pd2) => pd1.timestamp.CompareTo(pd2.timestamp));
return(data);
}
public static double DistanceFromRssi(PointData pd)
{
return(Math.Pow(10, (MEASURED_POWER - pd.rssi) / (10 * RoomData.GetEnvFactor(pd.id))));
}
