摘要 |
The accuracy of location estimates based on time-of-arrival measurements may be improved using a variety of different approaches. In some approaches, accuracy predictions are made before a location estimate is computed, and the location estimate is only computed when a high accuracy is predicted. In other approaches, a plurality of preliminary location estimates are computed, and the accuracy of each preliminary estimate is determined. A final location estimate is then based on the preliminary location estimates with the best determined accuracy. In some approaches, the accuracy predictions and determinations are based on geometric dilution of precision (GDOP) or a known topography of a region. In another approach, a subset of time-of-arrival measurements is fed into a closed-form algorithm to produce a preliminary location estimate. This preliminary location estimate is then used to initialize an open-form location algorithm. Optionally, more than one of these approaches may be combined. |