During an indoor positioning survey, a device records Bluetooth Low Energy (BLE) or WiFi radio signals from the environment. Simultaneously, motion unit sensors provide additional input that is used for optimization of position estimations. The sensors must be calibrated for optimal performance. A built-in sensor check warns if one or more sensors are not calibrated or if required permissions are not granted.
Use the Sensors section in the user profile to verify the app permissions and the status of Bluetooth, location, compass, gyroscope, and accelerometer sensors. To access the Sensors section, tap Profile
at the top of the map list.
The IPS Setup app includes support for both Bluetooth and WiFi. You can configure the data type to use for a survey in the Configuration section of the Profile page under Network. If you select WiFi, the Sensors list expands to include WiFi and WiFi Scanning Throttling options.
Verify app permissions
To verify app permissions, complete the following steps:
- Tap Profile .
The status of the sensors is displayed in the Sensors section.
- Ensure that the following permissions are enabled:
- Location
- Google Location Accuracy
- Compass Calibration
- Bluetooth
Additionally, if Wi-Fi is selected as the option for the Survey Radio Type setting, ensure the following permissions are enabled:
- Wi-Fi
- Wi-Fi Scanning Throttling
Note:
Wi-Fi scan throttling is enabled by default on Android devices and can be disabled in developer mode. Learn more about configuring Wi-Fi scanning throttling.
Verify compass accuracy
Use your device's compass to determine its heading. Compass accuracy refers to the deviation between the reported heading and the true geomagnetic heading.
Note:
Due to hardware differences across Android devices, the compass may need to be calibrated before conducting a survey. Compass accuracy can be categorized into one of the following states:
- High—The status is displayed as OK in green.
- Medium—The status is displayed as Medium in orange.
- Low—The status is displayed as Low in yellow.
- Poor/Unreliable—The status is displayed as Calibrate in red.
If the compass accuracy is high, medium, or low, you can perform a survey. If the compass accuracy is poor, calibrate the compass before conducting a survey.
To calibrate the compass of your device, complete the following steps:
- Open IPS Setup and sign in if necessary.
- Tap Profile at the top of the map list screen.
If the compass accuracy is poor, a request to calibrate it appears in red. Calibrate the compass by moving the phone in a figure-eight shape and pull down on the screen to refresh the status. If the accuracy is high, calibration is not necessary. When it is medium or low, calibration is recommended but not required.
Alternatively, after loading a map from the list, tap the Sensor Check status bar when it is shown at the top of Map mode. The Sensor Check bar only appears when the app is in Map or Survey mode when one or more sensors are not calibrated, or if the required permissions are not granted.
You can calibrate the compass at any time without accessing the Sensor Check list.
Note:
If your survey device is not equipped with a compass or a gyroscope, it may not meet sensor calibration requirements. If this is the case, switch to a device that is equipped with these sensors to successfully collect the necessary data.
Regardless of the compass accuracy, you can still test the positioning in Map mode if the Indoor Positioning Data Service is available.
Configure Wi-Fi scan throttling
The IPS Setup app includes support for Wi-Fi and Bluetooth. You can configure the Survey Radio Type in the Configuration section of the Profile page under Network.
Note:
The app supports the Wi-Fi recorder data type on Android 10 and later.
After selecting Wi-Fi as the option for Survey Radio Type, the Wi-Fi Scanning Throttling option appears in the Sensors section. Wi-Fi throttling is enabled by default on Android devices. This means that each foreground app can scan four times in a two-minute period, allowing for a burst of scans in a short time, and background apps can scan once in a 30-minute period.
Learn more about the Wi-Fi scan throttling settings
To record Wi-Fi sensor data, you must disable Wi-Fi scanning throttling.
To disable Wi-Fi scan throttling, complete the following steps:
- Enable developer options on the Android device.
Once enabled, Developer options appear in the device's Settings app.
- Choose Developer options and turn off Wi-Fi scan throttling.
- Return to the IPS Setup app and ensure that Wi-Fi Scanning Throttling is disabled.
Path snapping
When preparing maps for performing surveys and positioning testing, you can create pathway features to enable path snapping functionality for your map. If pathways are configured for path snapping, the functionality is enabled by default. After the survey has been completed and the reference Indoor Positioning Data Service is configured for your map, positioning testing can be performed. Optionally, during the positioning testing, you can compare the location indicator accuracy with the path snapping feature enabled and disabled. You can enable and disable the feature by turning Path Snapping on or off in the profile menu.
To visualize the Pathways feature class, turn on Show Paths.