Reliability and the accuracy of position-finding methods by estimation of the Rice factor of a radio link
AssigneeInfineon Technologies AG
InventorsAndreas Schmid, André Neubauer
Life of this patent
Estimating the term…
Abstract
In order to improve the reliability and the accuracy of a position-finding method such as the GPS method, the quality of a radio link which is used for the position-finding method is determined by estimating a parameter, in particular the Rice factor of the amplitude distribution density, which is characteristic of the ratio of the strength of a signal transmitted via a line-of-sight path, with respect to the strength of the signals transmitted via non-line-of-sight paths.
Claims10
A method for determination of the quality of a radio link, in which the radio signals propagate via two or more propagation paths, comprising:
- estimating a parameter that is characteristic of a signal strength of a received signal that is transmitted via a line-of-sight path, with respect to a strength of received signals transmitted via non-line-of-sight paths;
- and
- assuming a Rice distribution as the distribution function for the signal strength amplitude, wherein the estimated parameter comprises a Rice factor (K), and wherein the Rice factor is estimated using:
- K
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- where R is the amplitude of the sample values of the received signal and Ê{x} is approximated by a running averaging of x.
A method for determination of the quality of a radio link, in which the radio signals propagate via two or more propagation paths, comprising:
- estimating a parameter that is characteristic of a signal strength of a received signal that is transmitted via a line-of-sight path, with respect to a strength of received signals transmitted via non-line-of-sight paths;
- and
- assuming a Rice distribution as the distribution function for the signal strength amplitude, wherein the estimated parameter comprises a Rice factor (K), and wherein the Rice factor is estimated using:
- K
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- where R is the amplitude of the sample values of the received signal and Ê{x} is approximated by a running averaging of x.
A method for finding the position of a mobile station by means of a radio link between the mobile station and at least one reference station, comprising:
- determining a quality of the radio link, wherein the quality determination comprises estimating a parameter that is characteristic of a signal strength of a received signal that is transmitted via a line-of-sight path, with respect to a strength of received signals transmitted via non-line-of-sight paths;
- and
- using the parameter to decide whether the signal received from the reference station is to be used for position finding;
- or
- using the signals associated with the line-of-sight path and non line-of-sight paths for position finding after assigning weights to each of the signals by means of a weighting factor based on the value of the parameter for each of the signals.
Dependencies are inferred from the claim text.