System and method to estimate the location of a receiver in a multi-path environment
US7030814B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 2002 |
| Grant date | Apr 18, 2006 |
| Priority date | — |
| Expiry date | Dec 25, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
System and method to determine the location of a receiver in a multipath environment are provided. The received signal is correlated with the reference signals associated with the transmitting sources. Each correlation function is processed to derive various types of signal constraints, such as probability densities and uncertainty regions or intervals. In some embodiments, these constraints are for the code-phases and the Doppler frequencies. These signal constraints are transformed into constraints on the receiver variables and then fused together into a unified receiver constraint. A-priori constraints, such as constraints on the location of the receiver or the timestamp, may be incorporated into the unified receiver constraint. Some embodiments estimate a location based also on the estimated Doppler frequency. The constraints used by the invention are based on models of multipath effects and are geared towards mitigating these effects. In one of these models, a probability density for code-phase is obtained by convolving a gaussian distribution with an exponential distribution that describes the extra delay introduced by multipath. Another approach is based on identifying outli…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.