# AWS IoT Core Device Location
<a name="device-location"></a>


|  | 
| --- |
| Before using the AWS IoT Core Device Location feature, review the Terms and Conditions for this feature. Note that AWS may transmit your geolocation search request parameters, such as the location data used to run searches, and other information to your chosen third party data provider, which may be outside of the AWS Region that you are currently using. The third party provider and the solver to be used is chosen based on the input payload received. For more information, see [AWS Service Terms](https://aws.amazon.com/service-terms). | 

Use AWS IoT Core Device Location to test the location of your IoT devices using third-party solvers. *Solvers* are algorithms provided by third-party vendors that resolve measurement data and estimate the location of your device. By identifying the location of your devices, you can track and debug them in the field to troubleshoot any issues.

The measurement data collected from various sources is resolved, and the geolocation information is reported as a [GeoJSON](https://geojson.org/) payload. The GeoJSON format is a format that's used to encode geographic data structures. The payload contains the latitude and longitude coordinates of your device location, which are based on the [ World Geodetic System coordinate system (WGS84)](https://gisgeography.com/wgs84-world-geodetic-system/).

**Topics**
+ [Measurement types and solvers](#location-measurement-types)
+ [How AWS IoT Core Device Location works](#location-how-works)
+ [How to use AWS IoT Core Device Location](#location-how-use)
+ [Resolving location of IoT devices](device-location-resolve-solvers.md)
+ [Resolving device location using AWS IoT Core Device Location MQTT topics](device-location-reserved-topics.md)
+ [Location solvers and device payload](device-location-solvers-payload.md)
+ [Advanced configuration for AWS IoT Core Device Location](device-location-advanced-configuration.md)

## Measurement types and solvers
<a name="location-measurement-types"></a>

AWS IoT Core Device Location partners with third-party vendors to resolve the measurement data and to provide an estimated device location. The following table shows the measurement types and the third-party location solvers, and information about supported devices. For information about LoRaWAN devices and configuring device location for them, see [Configuring position of LoRaWAN resources](https://docs.aws.amazon.com/iot-wireless/latest/developerguide/lorawan-configure-location.html).

**Note**  
General IoT devices and Sidewalk devices can use the device location MQTT topics to obtain the location information. For Wi-Fi, Cellular, and IP address measurement types, if the devices publish the measurement data to the [reserved topics](device-location-reserved-topics.md) in the defined GeoJSON format, AWS IoT Core Device Location can resolve the location of the device. For GNSS measurement type, the device must have the LR11xx chip to scan the measurement data for obtaining the resolved location information using the GNSS solver. For information about obtaining location information for LoRaWAN devices, see [Configuring position for LoRaWAN resources](https://docs.aws.amazon.com/iot-wireless/latest/developerguide/lorawan-configure-location.html) in the *AWS IoT Wireless documentation*.


**Measurement types and solvers**  

| Measurement type | Third-party solvers | Supported devices | 
| --- | --- | --- | 
| Wi-Fi access points | Wi-Fi based solver  | General IoT devices, LoRaWAN, and Amazon Sidewalk devices | 
| Cellular radio towers: GSM, LTE, CDMA, SCDMA, WCMDA, and TD-SCDMA data | Cellular based solver  | General IoT devices, LoRaWAN, and Amazon Sidewalk devices | 
| IP address | IP reverse lookup solver | Any IoT device that connects over TCP/IP | 
| GNSS scan data (NAV messages) | GNSS solver | General IoT devices, LoRaWAN, and Amazon Sidewalk devices | 
| Bluetooth Low Energy (BLE) | BLE based solver | Amazon Sidewalk devices | 

For more information about the location solvers and examples that show the device payload for the various measurement types, see [Location solvers and device payload](device-location-solvers-payload.md).

## How AWS IoT Core Device Location works
<a name="location-how-works"></a>

The following diagram shows how AWS IoT Core Device Location collects measurement data and resolves the location information of your devices.

![\[Image showing how AWS IoT Core Device Location uses your raw measurement data and resolves the device location.\]](http://docs.aws.amazon.com/iot/latest/developerguide/images/iot-device-location.png)


The following steps show how AWS IoT Core Device Location works.

1. 

**Receive measurement data**

   The raw measurement data related to your device location is first sent from the device. The measurement data is specified as a JSON payload.

1. 

**Process measurement data**

   The measurement data is processed, and AWS IoT Core Device Location chooses the measurement data to be used, which can be Wi-Fi, cellular, GNSS scan, or IP address information.

1. 

**Choose solver**

   The third-party solver is chosen based on the measurement data. For example, if the measurement data contains Wi-Fi and IP address information, it chooses the Wi-Fi solver and the IP reverse lookup solver.

1. 

**Obtain resolved location**

   An API request is sent to the solver providers requesting to resolve the location. AWS IoT Core Device Location then gets the estimated geolocation information from the solvers.

1. 

**Choose resolved location**

   The resolved location information and its accuracy is compared, and AWS IoT Core Device Location chooses the geolocation results with the highest accuracy.

1. 

**Output location information**

   The geolocation information is sent to you as a GeoJSON payload. The payload contains the WGS84 geo coordinates, the accuracy information, confidence levels, and the timestamp at which the resolved location was obtained.

## How to use AWS IoT Core Device Location
<a name="location-how-use"></a>

The following steps show how to use AWS IoT Core Device Location.

1. 

**Provide measurement data**

   Specify the raw measurement data related to the location of your device as a JSON payload. To retrieve the payload measurement data, go to your device logs, or use CloudWatch Logs, and copy the payload data information. The JSON payload must contain one or more types of data measurement. For examples that show the payload format for various solvers, see [Location solvers and device payload](device-location-solvers-payload.md).

1. 

**Resolve location information**

   Using the [Device Location](https://console.aws.amazon.com/iot/home#/device-location-test) page in the AWS IoT console or the [GetPositionEstimate](https://docs.aws.amazon.com/iot-wireless/latest/apireference/API_GetPositionEstimate.html) API operation, pass the payload measurement data and resolve the device location. AWS IoT Core Device Location then chooses the solver with the highest accuracy and reports the device location. For more information, see [Resolving location of IoT devices](device-location-resolve-solvers.md).

1. 

**Copy location information**

   Verify the geolocation information that was resolved by AWS IoT Core Device Location and reported as a GeoJSON payload. You can copy the payload for use with your applications and other AWS services. For example, you can send your geographical location data to Amazon Location Service using the [Location](location-rule-action.md) AWS IoT rule action.

The following topics show how to use AWS IoT Core Device Location and examples of device location payload.
+ [Resolving location of IoT devices](device-location-resolve-solvers.md)
+ [Location solvers and device payload](device-location-solvers-payload.md)