LoRa Cloud Geolocation Services

LoRa Cloud Geolocation Services provides simple JSON web APIs that can be easily integrated with a LoRaWAN network or application server to enable estimating the location of LoRa-based devices.

In general, LoRa allows locating devices withing approximately 50m, without the need for a geolocation hardware module and no extra power consumption. Instead, the RSSI, SNR and TOA metadata that are being sent as part of your device’s LoRa radio frames are used to estimate the location of your device. If your device can perform WiFi scans, scanning results can also be used to estimate your device’s location. This yields a significant cost reduction compared to GPS.

Also, LoRa Cloud Geolocation integration allows estimating the location of LR1110-based devices with transceiver firmware from their GNSS scans.

Three query types are supported in scope of this integration and will be demonstrated below:

• LoRa TOA/RSSI - allows computing the location estimates using TOA and/or RSSI information from a single or multiple LoRa frames (for all LoRa devices)
• GNSS - location estimates are computed from the information contained in the GNSS scan result messages (NAV messages) (for LR1110 transceiver-based devices only)
• TOA/WiFi - the initial device location estimation is performed using the scanned WiFi access points, but if this estimation is not valid, another estimation is performed based on TOA metadata from device’s LoRa radio frames (for all LoRa devices capable of performing WiFi scans)

The location of your gateway has to be publicly available for this integration, as it participates in the process of computing the end device location. This is disabled in The Things Stack by default, because the application (and end device) owner does not have be the one providing the gateway coverage. If you own the gateway, it is safe for you to explicitly allow to publish its location.

To make the gateway location public, tick the Gateway location → Public box when adding your gateway in The Things Stack Console.

If your gateway is already added in The Things Stack Console, go to your gateway’s settings, navigate to the Location tab on the left hand menu and tick the Privacy → Publish location box.

Before proceding with this guide, make sure you have completed the LoRa Cloud Setup guide.

Configure Geolocation Integration

To setup LoRa Cloud Geolocation integration, navigate to your application in The Things Stack.

On the left hand menu, select Integrations → LoRa Cloud. Click the Expand button next to the Geolocation services.

Next, copy the token you previously created in LoRa Cloud Modem & Geolocation Services portal and paste it in the Token field.

Choose the Query type depending on the type of data you want to use for estimating the location of your device. As mentioned earlier, you can choose LoRa TOA/RSSI, GNSS or TOA/WiFi query type.

If you choose LoRa TOA/RSSI, you also have an option to enable Multiframe location lookups. Multiframe mode allows using the sequence of radio frames (instead of just a single frame) to improve the device’s location estimation accuracy. Multiframe mode is reported to be more accurate than averaging multiple location results calculated from several single radio frames. If you choose multiframe mode, you can also set the Multiframe window size to tell how many historical messages should be sent as part of the final request, and Multiframe time window as the maximum age of considered historical messages.

The setting for the Server URL points to the LoRa Cloud Modem & Geolocation Services and is set by default. Changing this is unnecessary.

Finish by clicking the Set token button.

Obtain Location Solutions

This section will show you how to obtain the location estimates using LoRa® TOA/RSSI, GNSS and TOA/WiFi query types.

After you obtain the location results, you can further integrate your The Things Stack application with other third-party IoT platforms to visualize them, etc.

LoRa TOA/RSSI

At this point, when your LoRa device sends any uplink message and it gets picked up by at least 3 gateways, you will notice the location estimation results present in the Location solved message in The Things Stack Live data tab, as shown below.

Notice the Source: LORA_RSSI_GEOLOCATION which indicates the type of the query you chose for geolocation.

GNSS

When your LR1110 transceiver performs a GNSS scan and sends the resulting data in an uplink NAV message, you will see the location estimate present in the Location solved message in The Things Stack Live data tab, as shown below.

Notice the Source: GPS which indicates the type of the query you chose for geolocation.

TOA/WiFi

When your LoRa device performs a WiFi scan and sends a resulting uplink message, the payload contains the MAC addresses of WiFi adapters and RSSIs of scanned WiFi networks. You need to decode this payload using the uplink payload formatter function in a way that the decoded_payload object that is a part of the uplink_message contains the access point records, like so:

"decoded_payload": {
    "access_points": [
    {
        "bssid": "14:60:80:9a:19:58",
        "rssi": -20
    },
    {
        "bssid": "fc:f5:28:7b:07:e5",
        "rssi": -80
    }
  ]
}

If estimating the location based on WiFi access point records cannot be performed, the location will be estimated using the TOA information from LoRa radio metadata and gateway location. In both cases, you will see the location estimate present in the Location solved message in The Things Stack Live data tab, as shown below.

Notice the Source: WIFI_RSSI_GEOLOCATION which indicates the type of the query you chose for geolocation.