Radiosonde + sat track updates

server/src/sats.mjs

@@ -1,59 +1,234 @@
 import {cfg} from './config.mjs';
 import {isEqual} from '@ztimson/utils';
+import {randomUUID} from 'node:crypto';
 
 const HISTORY_LIMIT = 500;
 const POLL_MS = 5_000;
 const TTL_MS = 3 * 60_000;
+const MAX_PREDICTION_DT = 30;
+const MAX_AZ_ERROR = 35;
+const MAX_EL_ERROR = 20;
+const MAX_GROUND_DISTANCE_KM = 1000;
+const MAX_FREQ_ERROR_KHZ = 15;
+
+const satellites = new Map();
+
+function normalizeAzimuth(az) {
+	return ((az % 360) + 360) % 360;
+}
+
+function circularDistance(a, b) {
+	const diff = Math.abs(normalizeAzimuth(a) - normalizeAzimuth(b));
+	return Math.min(diff, 360 - diff);
+}
+
+function circularDelta(from, to) {
+	let delta = normalizeAzimuth(to) - normalizeAzimuth(from);
+	if (delta > 180) delta -= 360;
+	if (delta < -180) delta += 360;
+	return delta;
+}
+
+function haversineDistance(lat1, lon1, lat2, lon2) {
+	const R = 6371;
+	const dLat = (lat2 - lat1) * Math.PI / 180;
+	const dLon = (lon2 - lon1) * Math.PI / 180;
+	const a =
+		Math.sin(dLat / 2) ** 2 +
+		Math.cos(lat1 * Math.PI / 180) *
+		Math.cos(lat2 * Math.PI / 180) *
+		Math.sin(dLon / 2) ** 2;
+	return R * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
+}
+
+function calculateBearing(lat1, lon1, lat2, lon2) {
+	const φ1 = lat1 * Math.PI / 180;
+	const φ2 = lat2 * Math.PI / 180;
+	const λ = (lon2 - lon1) * Math.PI / 180;
+	const y = Math.sin(λ) * Math.cos(φ2);
+	const x = Math.cos(φ1) * Math.sin(φ2) - Math.sin(φ1) * Math.cos(φ2) * Math.cos(λ);
+	return normalizeAzimuth(Math.atan2(y, x) * 180 / Math.PI);
+}
 
 function parseWm(raw) {
 	const f = raw.replace(/<[^>]+>/g, '').split(',').map(s => s.trim());
-	const [latitude, longitude] = f[15].split('/').map(s => parseFloat(s));
-	const [az, el] = f[16].split('/').map(s => parseFloat(s));
+	const [latitude, longitude] = (f[15] || '').split('/').map(s => parseFloat(s));
+	const [az, el] = (f[16] || '').split('/').map(s => parseFloat(s));
 	return {
 		timestamp: Date.now(),
 		freqMHz: parseFloat(f[3]),
 		satellite: f[14],
-		latitude, longitude,
-		az, el,
+		latitude,
+		longitude,
+		az: normalizeAzimuth(az),
+		el,
 		packetRssi: parseFloat(f[21]),
 		packetSnr: parseFloat(f[22]),
 		freqError: parseFloat(f[23]),
 		crcOk: !/CRC ERROR/i.test(f[24]),
-	}
+	};
 }
 
-const satellites = new Map();
+function createTrack(reading) {
+	const id = randomUUID();
+	const track = {
+		id,
+		name: reading.satellite,
+		history: [],
+		lastSeen: reading.timestamp,
+		state: {
+			az: reading.az,
+			el: reading.el,
+			latitude: reading.latitude,
+			longitude: reading.longitude,
+			freqError: reading.freqError,
+			azVelocity: 0,
+			elVelocity: 0,
+			latitudeVelocity: 0,
+			longitudeVelocity: 0,
+			groundSpeedKmh: 0,
+			heading: null,
+			freqErrorVelocity: 0,
+			confidence: 0.25,
+		},
+	};
+
+	track.history.push(reading);
+	satellites.set(id, track);
+	return track;
+}
+
+function predictTrack(track, timestamp) {
+	const dtRaw = (timestamp - track.lastSeen) / 1000;
+	const dt = Math.max(0, Math.min(dtRaw, MAX_PREDICTION_DT));
+	const state = track.state;
+	return {
+		az: normalizeAzimuth(state.az + state.azVelocity * dt),
+		el: state.el + state.elVelocity * dt,
+		latitude: state.latitude + state.latitudeVelocity * dt,
+		longitude: state.longitude + state.longitudeVelocity * dt,
+		freqError: state.freqError + state.freqErrorVelocity * dt,
+		dt,
+	};
+}
+
+function scoreTrack(track, reading) {
+	if(!track || !reading) return Infinity;
+	const dt = (reading.timestamp - track.lastSeen) / 1000;
+	if(dt <= 0 || dt > MAX_PREDICTION_DT) return Infinity;
+	if(track.name !== reading.satellite) return Infinity;
+
+	const predicted = predictTrack(track, reading.timestamp);
+	const azError = circularDistance(predicted.az, reading.az);
+	const elError = Math.abs(predicted.el - reading.el);
+	if(azError > MAX_AZ_ERROR || elError > MAX_EL_ERROR) return Infinity;
+
+	let groundDistance = 0;
+	if(Number.isFinite(reading.latitude) && Number.isFinite(reading.longitude) && Number.isFinite(predicted.latitude) && Number.isFinite(predicted.longitude)) {
+		groundDistance = haversineDistance(predicted.latitude, predicted.longitude, reading.latitude, reading.longitude);
+		if(groundDistance > MAX_GROUND_DISTANCE_KM) return Infinity;
+	}
+
+	let freqErrorDifference = 0;
+	if(Number.isFinite(reading.freqError) && Number.isFinite(predicted.freqError)) {
+		freqErrorDifference = Math.abs(reading.freqError - predicted.freqError);
+		if(freqErrorDifference > MAX_FREQ_ERROR_KHZ) return Infinity;
+	}
+
+	return (azError * 4 + elError * 5 + groundDistance * 0.03 + freqErrorDifference * 0.15); // Lower = better
+}
+
+function updateTrack(track, reading) {
+	const previous = track.history.at(-1);
+
+	if (!previous) {
+		track.history.push(reading);
+		track.lastSeen = reading.timestamp;
+		return;
+	}
+
+	const dt = (reading.timestamp - previous.timestamp) / 1000;
+	if(dt <= 0) return;
+
+	const state = track.state;
+	const azVelocity = circularDelta(previous.az, reading.az) / dt;
+	const elVelocity = (reading.el - previous.el) / dt;
+	const latitudeVelocity = (reading.latitude - previous.latitude) / dt;
+	const longitudeVelocity = (reading.longitude - previous.longitude) / dt;
+	const distanceKm = haversineDistance(previous.latitude, previous.longitude, reading.latitude, reading.longitude);
+	const groundSpeedKmh = distanceKm / dt * 3600;
+	const heading = distanceKm > 0.01 ? calculateBearing(previous.latitude, previous.longitude, reading.latitude, reading.longitude) : state.heading;
+	const freqErrorVelocity = Number.isFinite(reading.freqError) && Number.isFinite(previous.freqError) ? (reading.freqError - previous.freqError) / dt : state.freqErrorVelocity;
+	const SMOOTHING = 0.35;
+
+	state.azVelocity = state.azVelocity * (1 - SMOOTHING) + azVelocity * SMOOTHING;
+	state.elVelocity = state.elVelocity * (1 - SMOOTHING) + elVelocity * SMOOTHING;
+	state.latitudeVelocity = state.latitudeVelocity * (1 - SMOOTHING) + latitudeVelocity * SMOOTHING;
+	state.longitudeVelocity = state.longitudeVelocity * (1 - SMOOTHING) + longitudeVelocity * SMOOTHING;
+	state.freqErrorVelocity = state.freqErrorVelocity * (1 - SMOOTHING) + freqErrorVelocity * SMOOTHING;
+	state.az = reading.az;
+	state.el = reading.el;
+	state.latitude = reading.latitude;
+	state.longitude = reading.longitude;
+	state.freqError = reading.freqError;
+	state.groundSpeedKmh = groundSpeedKmh;
+	state.heading = heading;
+
+	const prediction = predictTrack(track, reading.timestamp);
+	const predictionError = circularDistance(prediction.az, reading.az) + Math.abs(prediction.el - reading.el);
+
+	if(predictionError < 5) {
+		state.confidence = Math.min(1, state.confidence + 0.08);
+	} else if(predictionError < 15) {
+		state.confidence = Math.min(1, state.confidence + 0.03);
+	} else {
+		state.confidence = Math.max(0, state.confidence - 0.08);
+	}
+
+	track.lastSeen = reading.timestamp;
+	if(!isEqual(track.history.at(-1), reading)) {
+		track.history.push(reading);
+		if(track.history.length > HISTORY_LIMIT) track.history.shift();
+	}
+}
 
 function pruneStale() {
 	const now = Date.now();
-	for (const [name, bucket] of satellites) {
-		if (now - bucket.lastSeen > TTL_MS) satellites.delete(name);
+	for(const [id, track] of satellites) {
+		if(now - track.lastSeen > TTL_MS) satellites.delete(id);
 	}
 }
 
+function findBestTrack(reading) {
+	let bestTrack = null;
+	let bestScore = Infinity;
+	for(const track of satellites.values()) {
+		const score = scoreTrack(track, reading);
+		if(score < bestScore) {
+			bestScore = score;
+			bestTrack = track;
+		}
+	}
+	return {track: bestTrack, score: bestScore,};
+}
+
 export async function pollTinyGS() {
-	const { TINYGS_URL, TINYGS_AUTH } = cfg();
+	const {TINYGS_URL, TINYGS_AUTH} = cfg();
 	try {
 		const raw = await fetch(TINYGS_URL + '/wm', {
-			headers: TINYGS_AUTH ? {Authorization: `Basic ${TINYGS_AUTH}`} : {}
+			headers: TINYGS_AUTH ? {Authorization: `Basic ${TINYGS_AUTH}`} : {},
 		}).then(r => r.text());
 		const reading = parseWm(raw);
-		if (!reading.satellite || reading.satellite === '-') return;
-
-		const key = reading.satellite + '-' + reading.freqMHz;
-		let bucket = satellites.get(key);
-		if (!bucket) {
-			bucket = { history: [], lastSeen: 0 };
-			satellites.set(key, bucket);
-		}
-
-		bucket.lastSeen = reading.timestamp;
-		if (!isEqual(bucket.history.at(-1), reading)) {
-			bucket.history.push(reading);
-			if (bucket.history.length > HISTORY_LIMIT) bucket.history.shift();
-		}
+		if(!reading.satellite || reading.satellite === '-') return;
 
 		pruneStale();
+		const {track, score,} = findBestTrack(reading);
+		if(!track || !Number.isFinite(score)) {
+			createTrack(reading);
+			return;
+		}
+
+		updateTrack(track, reading);
 	} catch (err) {
 		console.error('[tinygs] poll failed', err);
 	}
@@ -63,8 +238,20 @@ setInterval(pollTinyGS, POLL_MS);
 
 export const getTinyGSData = () => {
 	pruneStale();
-	return Array.from(satellites.entries()).map(([name, bucket]) => ({
-		...bucket.history.at(-1),
-		history: bucket.history.slice(0, -1),
-	}));
-}
+	return Array.from(satellites.values()).map(track => {
+		const latest = track.history.at(-1);
+		return {
+			id: track.id,
+			satellite: track.name,
+			...latest,
+			altitudeKm: null,
+			velocity: {
+				v: track.state.groundSpeedKmh,
+				az: track.state.azVelocity,
+				el: track.state.elVelocity,
+			},
+			heading: track.state.heading,
+			history: track.history.slice(0, -1),
+		};
+	});
+};

server/src/server.mjs

@@ -15,7 +15,7 @@ import {dailyWeather, hourlyWeather} from './openmeteo.mjs';
 import {getTinyGSData} from './sats.mjs';
 import {getSpaceWeather} from './space.mjs';
 import {Aurora} from './aurora.mjs';
-import {getSondes} from './radiosonde.mjs';
+import {getSondes} from './sonde.mjs';
 
 // ── Uncaught error handlers ───────────────────────────────────────────────────
 

server/src/sonde.mjs

@@ -18,7 +18,6 @@ export async function getSondes() {
 		const t = sonde.latest_telem ?? {};
 
 		const history = (sonde.path ?? []).map(([latitude, longitude, altitude]) => ({
-			id,
 			latitude,
 			longitude,
 			altitude