How Does LoT work?
The Pixie Point
Each Pixie Point includes a 2.4GHz ISM controller, an 802.15.4a radio, power management unit, a power source (LiMnO2 primary battery) and a wide band antenna. It is controlled by embedded firmware that manages the Pixie Point operations, such as distance measurements, standard Bluetooth activities and unique Pixie Network Protocol actions.A small, efficient and incredibly powerful piece of hardware.
The SDK, running on an iOS device, is responsible for the local management of the Pixie Points. The key functions are to establish the connections to the Points, establish the Pixie Network (for multiple Points), managing raging activities and apply the Location Engine algorithms.
The accurate distance between Pixie Points is a must to create the accurate relative locations between points. Pixie uses the Time of Flight method.
With ToF, two Pixie Points measure the time it takes for RF signals to travel between each other. Measuring ToF leads to accurate and robust distance estimation, relying on the constant RF propagation speed (the speed of light). For maximum accuracy, Points are using an 802.15.4a Ultra Wide Band (UWB) two-way Time of Flight (TOF) measurement.
Pixies Points communicate with each other and form a robust self-managing network of things, that is completely private and secure.
The mesh network architecture provides 4 main benefits:
- Power optimization for the Points
- Range extension
- Location accuracy improvements. Using the network, the SDK can maintain matrix of distances between Points
The location engine calculates the exact location of a moving Pixie location tag relative to static anchor points.
The map is a composition of distances and relative angles between the Points. However, with multiple Points involved and real life noises in measurements, there is a need for the algorithmic engine to smooth and filter the raw measurements. We have brought our broad experience in this area so that the output map is accurate and reliable as possible.
Keeping security and privacy at the highest standards require account management that couples each Point to its owner. The Pixie Points belong to a specific account, not a specific device. Pixie Points ownership management is done in the Pixie Cloud.