Native positioning service
Last updated on December 7th, 2022
The native positioning is an additional service on top of data uplink subscription, the data uplink service is thus required to activate the service.
| Service | Description | Specifications | Pricing |
|---|---|---|---|
| Native positioning | 1 position every 4 received transmission, in average |
|
+ 30% extra cost |
Additionnal requirement
A transmitter certification with good frequency stability is necessary to access this option.
Service Access Model
- Complementary service: on top of Data uplink service. Messages received for data uplink service can be used to compute native location
- Dedicated: Specific short messages. Native location is calculated with dedicated Low power short transmissions for longer autonomy
- A combination of both types of messages
Pricing
Prices are based on Data uplink service + 30% extra cost. Discount can apply based on commitment and volumes.
Why use the native positioning?
- No need for GNSS receiver and antenna integration for smaller and less expensive devices
- Power saving solution for device positioning since it can be computed using messages containing useful data and thus does not require additional emissions
- 200m to 1km accuracy for static asset
- Insensitive to GNSS jamming
- Unforgeable Doppler based location
More information about the quality of this service here: Native positioning service accuracy.
How does it work? The Doppler effect
When a device transmits signals to the Kinéis satellites, it is possible to compute a position using the Doppler effect.
The Doppler Effect is the change in frequency of an electromagnetic wave that occurs when the source and observer are moving relative to each other.
In this case, the satellite is passing above the Kinéis device, which is considered relatively still for the duration of the satellite pass (~10mn) in comparison to the satellite (passing at about 8km/s). The onboard instrument measures the received frequency of each message received over the satellite pass. Considering that the transmitted frequency is constant from the device, tracing the evolution of the received frequency over time gives the Doppler curve (exemple hereunder), from which the location of the device is computed by the Kinéis Service Center (c.f. image Native positioning step by step).
The location is attributed to the Device for a cluster of several messages. Each message is not localized individually.
Native positioning has existed for 40 years! Argos has contributed to the knowledge of the migratory routes followed by animals thanks to the Doppler effect exploitation.
