ChirpStack Network Server supports geolocation by using an external geolocation-server service. You can either use ChirpStack Geolocation Server or implement your own (matching the expected API).
For using geolocation, you need to use gateways that are capable of providing a “fine-timestamp”. Some of these gateways encrypt this fine-timestamp.
When configuring the per gateway and board specific decryption key, ChirpStack Network Server will decrypt the fine-timestamp, before forwarding it to the geolocation-server. For getting this fine-timestamp decryption key, please contact your gateway vendor or Semtech.
ChirpStack Network Server support multi-frame geolocation to increase the geolocation accuracy. In the Device Profile it is possible to configure the:
Example:
When the TTL is set to 5 minutes (300 seconds) and the minimum buffer size is set to 3, then geolocation will only be used when there are at least 3 frames in the geolocation buffer that are received within the last 5 minutes.
When ChirpStack Network Server (using the Geolocation Server) is able to resolve the location of the device, it will forward this to the application-server.