basic algo that computes virtual location based on TTN gateway locations

server/src/index.ts

@@ -8,6 +8,38 @@ import lpTtnEndDeviceUplinksRoutes from "./controller/lpTtnEndDeviceUplinksContr
 import ttnGatewayReceptionRoutes from "./controller/ttnGatewayReceptionController";
 import wifiScanRoutes from "./controller/wifiScanController";
 
+interface LocationData {
+  rssi: number;
+  latitude: number;
+  longitude: number;
+}
+
+function calculateTtnGatewayLocation(dataList: LocationData[]): { latitude: number, longitude: number } {
+  if (!dataList || dataList.length === 0) {
+    throw new Error("The data list is empty or undefined.");
+  }
+
+  let totalWeight = 0;
+  let weightedLatitude = 0;
+  let weightedLongitude = 0;
+
+  // Loop through the dataList and calculate weighted sums based on RSSI
+  dataList.forEach(point => {
+    const weight = 1 / Math.abs(point.rssi); // Higher RSSI (closer to 0) gives more weight
+    totalWeight += weight;
+    weightedLatitude += point.latitude * weight;
+    weightedLongitude += point.longitude * weight;
+  });
+
+  // Calculate the weighted average to get the virtual location
+  const virtualLocation = {
+    latitude: weightedLatitude / totalWeight,
+    longitude: weightedLongitude / totalWeight
+  };
+
+  return virtualLocation;
+}
+
 dotenv.config();
 
 const app = express();
@@ -21,6 +53,17 @@ app.use("/api/wifi-scans", wifiScanRoutes);
 app.use("/api/ttn-gateway-receptions", ttnGatewayReceptionRoutes);
 app.use("/api/locations", locationRoutes);
 
+const dataList: LocationData[] = [
+  //sensecap_exporter_2024-10-18_12-52-30.json
+  { rssi: -108, latitude: 51.875759063444335, longitude: 4.448537528514863 },
+  { rssi: -114, latitude: 51.8875851, longitude: 4.4919652 },
+  { rssi: -106, latitude: 51.9102795122954, longitude: 4.48074765239573 },
+  { rssi: -103, latitude: 51.9111671447754, longitude: 4.46313190460205 }
+];
+
+const virtualLocation = calculateTtnGatewayLocation(dataList);
+console.log("TTN Gateway location:", virtualLocation);
+
 app.listen(PORT, () => {
-  console.log(`🚀 Server läuft auf http://localhost:${PORT}`);
+  console.log(`🚀 Server runs here: http://localhost:${PORT}`);
 });