GNSS position solver for Semtech LR1110 / LR1120 trackers

SHA-256:

2dbaa921c24c9d5f362c0ea77bbc093535d4bb42600122aa9be0a12558e43dcb

The archive also includes a file manifest, build information and dependency licences.

curl -X POST https://gnss-solver.com/v1/solve/lr11xx -H "content-type: application/json" -d '{
  "format": "nav3",
  "payload": "<0x040D result hex, destination byte optional>",
  "gps_week": 2435
}'

Replace 2435 with the full GPS week of your capture; it is an example, not a permanent setting. If you have a key, add -H "x-api-key: YOUR_API_KEY". Omit that header for the anonymous trial. Keep keys on your backend, not in publicly served code.

Response: { position: {lat, lon, alt}, horizontal_accuracy_m, satellites_used, accepted, confidence, quality: { residual_rms_m, geometry }, solve_ms }. Use only accepted: true results. Rejections include reason codes. horizontal_accuracy_m is an estimate, not a guaranteed error limit; measurement_epoch_gpst identifies the solver’s estimated observation epoch, which may differ from upload time.

Check the HTTP status as well as accepted. An HTTP 200 rejection is a positioning decision; retrying the same packet with the same orbit data does not improve it. For HTTP 429, respect Retry-After if present; otherwise back off for a per-minute limit or wait until the next UTC day for a daily limit. For temporary service errors or timeouts, retry with increasing delays and a small retry limit.

Example response shapes (illustrative, fields omitted):

{ "accepted": true, "position": { "lat": 49.30171, "lon": -123.14166, "alt": 30 }, "horizontal_accuracy_m": 20 }
{ "accepted": false, "position": null, "reasons": ["invalid-nav3-structure"] }

Optional fields on the solve request let you choose how strict the acceptance is, from a tight pin to a rough area:

curl -X POST https://gnss-solver.com/v1/solve/lr11xx -H "content-type: application/json" -d '{
  "payload": "<hex>", "gps_week": 2435,
  "mode": "precision",            // only accept fixes ≤ 40 m (or "balanced" = ≤ 90 m)
  "max_accuracy_m": 50            // OR your own ceiling: reject anything worse than 50 m
}'

• "mode": "precision" — accept only fixes with an estimated accuracy ≤ 40 m, else reject.
• "mode": "balanced" — the same at ≤ 90 m.
• "max_accuracy_m": N — your own ceiling; if mode is also set, the tighter ceiling applies. Rejects any fix whose horizontal_accuracy_m is worse than that ceiling.
• Omit both — accept whatever the strict solver already trusts (no accuracy cap).

Low-power / best-effort mode. For sparse-sky single scans that the strict solver rejects, opt in to a weaker fix that is reported honestly and sanity-checked against your last known position:

curl -X POST https://gnss-solver.com/v1/solve/lr11xx -H "content-type: application/json" -d '{
  "payload": "<hex>", "gps_week": 2435,
  "best_effort": true,
  "anchor": { "lat": 48.6, "lon": -123.5 },   // last known position (optional but recommended)
  "anchor_max_km": 5                           // reject fixes this far from the anchor (default 5)
}'

• Accepts lower-redundancy fixes the strict solver would refuse; the response is tagged "mode": "best_effort" with a low confidence.
• Best-effort reports at least 75 m of uncertainty. That final reported value must pass your accuracy ceiling; mode: "precision" (40 m) therefore rejects best-effort fixes.
• horizontal_accuracy_m is floored so it never claims false precision — treat it as a rough area, not a pin.
• The anchor gate drops implausibly-far solutions (a common failure of weak fixes); a rejected one returns code: "anchor-distance-exceeded".
• The default strict behaviour is unchanged unless you set best_effort. Leave it off for anything safety- or billing-sensitive.

curl -X POST https://gnss-solver.com/v1/solve/lr11xx/multi -H "content-type: application/json" -d '{
  "captures": [
    { "payload": "<scan 1 hex>", "capture_time_gpst": 1472142795, "detected_sats": [ ... ] },
    { "payload": "<scan 2 hex>", "capture_time_gpst": 1472142817, "detected_sats": [ ... ] },
    { "payload": "<scan 3 hex>", "capture_time_gpst": 1472142839, "detected_sats": [ ... ] }
  ],
  "assist_position": { "lat": 49.28, "lon": -123.12 }
}'

2–6 captures within an hour, solved together with one shared position; a bad scan is dropped automatically. Same response shape plus frames: { given, solved, used, dropped }. Counts as one solve.

curl https://gnss-solver.com/v1/almanac/full

A fresh full-almanac image built from public data every day, in the shape the old LoRa Cloud endpoint returned, so existing firmware keeps working.

Developers may explicitly opt in to private rejected-payload diagnostics with allow_debug_payload_retention: true; when enabled by the operator, up to the first 32 payload bytes may be retained for at most 30 days. This demo does not opt in.

Privacy. By default, packets and positions you submit are solved in memory and discarded; the optional rejected-payload diagnostics described above are the exception. We do not retain solved positions through this option. We keep aggregate counters (solves per day) and a short-lived, hashed client identifier for rate limiting. The page uses privacy-friendly, cookieless, self-hosted analytics (Umami) that records only aggregate page visits, with no cookies, no personal data and no cross-site tracking; it loads no advertising or tracking scripts, and fonts are served from this site. Map tiles are fetched from OpenStreetMap when a result is shown, which reveals only the map area to them. Emails you send us are kept to answer them.

Trial terms. The hosted endpoint is a free trial for evaluation: fair-use daily limits, no uptime commitment, results provided as-is without warranty. Don't rely on it for safety-critical use. Paid access requires an agreed plan; the anonymous trial does not automatically create a paid account. There is no licence to buy.