Method and apparatus for satellite positioning system based time measurement
First Claim
1. A computer readable storage medium containing executable computer program instructions which when executed cause a digital processing system to perform a method comprising:
- receiving at an entity a first record of at least a portion of a satellite data message of a satellite positioning system;
comparing said first record with a second record of said satellite data message wherein said first record and said second record overlap at least partially in time;
determining a time from said comparing step, said time indicating when said first record was received at a remote entity.
0 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for measuring time related to satellite data messages which are used with satellite positioning systems (SPS). In one method, a first record of at least a portion of a satellite data message is received at an entity, which is typically a basestation. The first record is compared with a second record of the satellite data message, where the first record and the second record overlap at least partially in time. Then a time is determined from this comparison, and this time indicates when the first record (or the source from which the first record was obtained) was received at a remote entity which is typically a mobile SPS receiver. Various other methods of the invention are described and various apparatuses of the invention are also described. The methods and apparatuses measure time of day using SPS signals without reading the satellite data messages which are transmitted as data within these signals. The methods and apparatuses are suitable for situations in which the received signal level is too weak to allow reading of the satellite data messages.
-
Citations
25 Claims
-
1. A computer readable storage medium containing executable computer program instructions which when executed cause a digital processing system to perform a method comprising:
-
receiving at an entity a first record of at least a portion of a satellite data message of a satellite positioning system; comparing said first record with a second record of said satellite data message wherein said first record and said second record overlap at least partially in time; determining a time from said comparing step, said time indicating when said first record was received at a remote entity. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A processor readable storage medium containing executable digital processor instructions which when executed cause a digital processing system to perform a method comprising:
-
receiving at a mobile satellite positioning system (SPS) receiver a first record of at least a portion of a satellite data message; receiving at said mobile SPS receiver a second record of said satellite data message, wherein said first record and said second record overlap at least partially in time; comparing said first record with said second record; determining a time from said comparing, said time indicating when said first record was received at said mobile SPS receiver. - View Dependent Claims (20, 21, 22, 23, 24, 25)
-
Specification