LOCATION ERROR RADIUS DETERMINATION

摘要

A system and method determining an error radius reflecting the accuracy of a calculated position of a processing device is provided. A data structure includes an error radius mapped to a scaled geographic area or “tile” comprising an area in which a calculated position may be determined. The data structure may include a plurality of first fields identifying a scaled geographic area based on a global projection reference system, and a plurality of second fields identifying, for each of the first fields, a position error radius associated with a scaled geographic area and level. For any calculation of an inferred position based on beacon observations, a rapid lookup of the corresponding scaled area including the new inferred position in the data structure returns an error radius for the new inferred position.

主权项

1. A computer implemented method of determining an error radius for a calculated position, comprising:
providing a data structure including a plurality of first fields identifying a scaled geographic area based on a global projection reference system, the system divided into scaled geographic areas and having multiple levels of areas of different size, and a plurality of second fields identifying, for each of the first fields, a position error radius associated with a scaled geographic area and level, each position error radius calculated to be a maximum error radius for at least a threshold percentage of inferred positions in the associated scaled geographic area; determining a scaled geographic area associated with the calculated position; and returning a corresponding error radius mapped to a scaled geographic area associated with the calculated position.