Method and apparatus for determining time in a satellite positioning system
First Claim
1. A method for determining a reference time associated with a satellite positioning system, said method comprising:
- estimating a position of an entity relative to a set of satellites, said estimation being associated with a first time measurement, wherein said first time measurement and said reference time differ by an offset;
determining a relative velocity of said set of satellites; and
based on said relative velocity of said set of satellites and said estimated position, determining said offset between said first time measurement and said reference time.
2 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for determining a reference time associated with a satellite positioning system. In turn, the reference time, in one embodiment, may be used to determine other navigational information. Such navigational information may include, for example, the location/position of a satellite positioning system (SPS) receiver. In one embodiment, a relative velocity between an SPS receiver and a set of one or more satellites is used to determine an offset between time as indicated by the SPS receiver and the reference time. According to another embodiment of the invention, an error statistic is used to determine the reference time. According to yet another embodiment of the invention, two records, each representing at least a portion of a satellite message, are compared to determine time. In one implementation, the SPS receiver is mobile and operates in conjunction with a basestation to determine time and/or other navigational information according to one or a combination of the methods described.
224 Citations
40 Claims
-
1. A method for determining a reference time associated with a satellite positioning system, said method comprising:
-
estimating a position of an entity relative to a set of satellites, said estimation being associated with a first time measurement, wherein said first time measurement and said reference time differ by an offset;
determining a relative velocity of said set of satellites; and
based on said relative velocity of said set of satellites and said estimated position, determining said offset between said first time measurement and said reference time. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 40)
-
-
20. A method for determining a reference time associated with a satellite positioning system, said method comprising:
-
an entity estimating a first value associated with a position of a set of satellites relative to said entity, said estimated first value being associated with a first time measurement, wherein said first time measurement associated with said values and said reference time associated with said satellite positioning system differ by an offset;
calculating an error statistic for said first value; and
based on said error statistic, determining said offset between said first time measurement and said reference time associated with said satellite positioning system. - View Dependent Claims (21, 22, 23, 24, 25, 26, 27, 28)
-
-
29. An apparatus for determining a reference time associated with a satellite positioning system, said apparatus comprising:
-
a storage unit, to store a set of position values, said position values to indicate a relative position of a set of satellites, and wherein each of said set of position values is associated with a time of measurement that differs from said reference time by an offset; and
a processing unit, coupled to said storage unit, to determine said offset based on said set of position values and an estimate of a relative velocity of each of said set of satellites. - View Dependent Claims (30, 31, 32, 33, 34, 35, 36, 37, 38, 39)
-
Specification