Location fix from unknown position
First Claim
1. An apparatus for determining a location of a receiver by means of signals received by the receiver from a plurality of satellites, the apparatus including:
- a processor executing an algorithm, the algorithm configuring the processor to;
when an estimate of the location of the receiver is unavailable, determine an approximate location of the receiver and input the approximate location into the algorithm as the estimate of the location of the receiver,restrict the approximate location of the receiver by performing a Doppler fix based on the received satellite signals or by computing a visibility horizon associated with the satellite positions relative to the receiver,identify and prioritize ambiguities in pseudoranges to the satellites from the restricted approximate location of the receiver, anddetermine the location of the receiver by applying the pseudoranges, according to the respective identified and prioritized ambiguities, to a location algorithm.
2 Assignments
0 Petitions
Accused Products
Abstract
An apparatus for determining a location of a receiver by using signals received by the receiver from a number of satellites, the apparatus being configured to, when the receiver has been unable to decode a time-of-transmission from the satellite signals, determine a location for the receiver by use of an algorithm that takes an estimate of the location of the receiver as an input, and, when an estimate of the location of the receiver is unavailable, determine an approximate location of the receiver in dependence on the satellite signals and input that approximate location into the algorithm as the estimate of the location of the receiver.
74 Citations
23 Claims
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1. An apparatus for determining a location of a receiver by means of signals received by the receiver from a plurality of satellites, the apparatus including:
a processor executing an algorithm, the algorithm configuring the processor to; when an estimate of the location of the receiver is unavailable, determine an approximate location of the receiver and input the approximate location into the algorithm as the estimate of the location of the receiver, restrict the approximate location of the receiver by performing a Doppler fix based on the received satellite signals or by computing a visibility horizon associated with the satellite positions relative to the receiver, identify and prioritize ambiguities in pseudoranges to the satellites from the restricted approximate location of the receiver, and determine the location of the receiver by applying the pseudoranges, according to the respective identified and prioritized ambiguities, to a location algorithm. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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19. A method for determining a location of a receiver when the receiver has been unable to decode a time-of-transmission from signals received by the receiver from a plurality of satellites and an estimate of the location of the receiver is unavailable, the method comprising:
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determining, by a processor, an approximate location of the receiver based on satellite signals from the plurality of satellites; inputting, by the processor that approximate location into an algorithm, as an estimate of the location of the receivers; restricting, by the processor, the approximate location of the receiver by performing a Doppler fix based on the received satellite signals or by computing a visibility horizon associated with the satellite positions relative to the receiver, computing, by the processor, pseudoranges to the visible satellites from the restricted approximate location of the receiver, identifying and prioritizing, by the processor, ambiguities in the pseudoranges, and determining, by the processor, the location of the receiver based on the identified and prioritized ambiguities in the pseudoranges.
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20. A non-transitory computer-readable medium encoded with instructions, that when executed by an apparatus for determining a location of a receiver by means of signals received by the receiver from a plurality of satellites, cause the apparatus to:
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when an estimate of the location of the receiver is unavailable, determine an approximate location of the receiver based on the satellites and input the approximate location into the algorithm as the estimate of the location of the receiver, restrict the approximate location of the receiver by performing a Doppler fix based on the received satellite signals or by computing a visibility horizon associated with the satellite positions relative to the receiver, identify and prioritize ambiguities in pseudoranges to the satellites from the restricted approximate location of the receiver, and determine the location of the receiver by applying the pseudoranges, according to the respective identified and prioritized ambiguities, to a location algorithm.
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21. An apparatus configured to determine a region of the Earth'"'"'s surface within which a receiver is located, the apparatus including:
a processor executing an algorithm, the algorithm configuring the processor to; identify a plurality of visible satellites from which that receiver is receiving signals; and determine a region of the Earth'"'"'s surface from which it is possible to simultaneously receive signals from the visible satellites as an approximate location of the receiver, and restrict the approximate location of the receiver by performing a Doppler fix based on the received satellite signals or by computing a visibility horizon associated with the satellite positions relative to the receiver in order to identify and prioritize ambiguities in pseudoranges to the visible satellites from the restricted approximate location of the receiver.
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22. A method for determining a region of the Earth'"'"'s surface within which a receiver is located comprising:
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identifying, by a processor, a plurality of visible satellites from which the receiver is receiving signals; and determining, by the processor, a region of the Earth'"'"'s surface from which it is possible to simultaneously receive signals from the visible satellites as an approximate location of the receiver, and restricting, by the processor, the approximate location of the receiver by performing a Doppler fix based on the received satellite signals or by computing a visibility horizon associated with the satellite positions relative to the receiver in order to identify and prioritize ambiguities in pseudoranges to the visible satellites from the restricted approximate location of the receiver.
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23. A non-transitory computer-readable medium encoded with instructions, that when executed by an apparatus configured to determine a region of the Earth'"'"'s surface within which a receiver is located, cause the apparatus to:
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identify a plurality of visible satellites from which that receiver is receiving signals; and determine a region of the Earth'"'"'s surface from which it is possible to simultaneously receive signals from the visible satellites as an approximate location of the receiver, and restricting, by the processor, the approximate location of the receiver by performing a Doppler fix based on the received satellite signals or by computing a visibility horizon associated with the satellite positions relative to the receiver in order to identify and prioritize ambiguities in pseudoranges to the visible satellites from the restricted approximate location of the receiver.
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Specification