Tesla's New Patent Improves Navigation System for Autopilot

Tesla published a patent: 'System and methods for vehicle positioning'

Patent filing date: January 13, 2020
Patent publication date: May 14, 2020

The patent describes various vehicle technologies for improving positioning accuracy despite various factors that affect signals from navigation satellites. Such positioning accuracy is increased via determining an offset and communicating the offset in various ways or via sharing of raw positioning data between a plurality of devices, where at least one knows its location sufficiently accurately, for use in differential algorithms.

Navigation satellites transmit multiple signals to a positioning receiver, which can determine its position with a certain accuracy based on the signals. Satellite geometry, signal blockage, ionospheric perturbation, atmospheric conditions, or others, affect the signals such that that the accuracy of determining the position of the receiver is reduced.

For example, a smartphone with a positioning receiver may be able to determine its position to within 5 meters of the smartphone. But, the accuracy of the position determination may worsen when the receiver is in proximity of buildings, bridges, trees, or other structures.

Of course, this may be enough for some positioning apps, but greater accuracy is desirable for other apps, including autonomous driving. Accordingly, there is a desire to provide greater positioning accuracy despite the factors that affect the signals from the navigation satellites.

The patent says that vehicles are a kind of reference station that can receive and transmit data. When using the vehicle as a reference station, the vehicle can:

• receive a set of correction data from a stationary first vehicular client;
• locate a second vehicular client with respect to the first vehicular client based on a first vehicular client and the first value corresponding to the second vehicular client being in spatial proximity to first vehicular client, the second value corresponding to the second vehicular client being in temporal proximity to the first vehicular client; and
• send the set of correction data to the second vehicular client such that the second vehicular client is able to correct a positioning measurement resulting based on the set of correction data.

FIG. 1 shows a schematic diagram of an embodiment of a vehicle according to this disclosure.
Source: Tesla patent

This patent discloses inventions that improve positioning accuracy despite the factors that affect the signals from the navigation satellites. The inventions increase such positioning accuracy via determining and applying offsets (corrections) in various ways, or via sharing of raw positioning data between a plurality of devices, where at least one knows its location sufficiently accurately, for use in differential algorithms.

For example, some of such techniques can include:

• a reference station sharing a positional offset with an automobile;
• a reference station calculating and sharing a set of parameters (offsets/corrections) for various error components including atmospheric, orbital, and clock, and/or
• a reference station sharing its raw GNSS data so that vehicles can remove errors through differencing, or other calculations.

For example, the offset can be a positioning offset, i.e., an actual offset, a correction offset per satellite or per a plurality of satellites, a vehicular offset generated via a vehicle processing raw data when the vehicle is not in signal communication with a base station, or others.

This patent describes inventions that improve the navigation of Tesla cars. In fact, the more Tesla cars there are in the world, the more accurate their navigation will be. This, in turn, brings us closer to a more accurate and safer Autopilot, which, based on the data of satellites and other cars, can be more perfect.

Featured image: Tesla