US6052081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for satellite positioning system based time measurement
Assignee: SnapTrack Inc
•
Filing: 1998-05-07
•
Granted: 2000-04-18
•
Expires: 2018-05-07
Abstract
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.
Inventors
- 👤 Norman F. Krasner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:54
CPC Classifications
G; G01; G01S; G01S5/00; G01S5/0009; G01S19/00; G01S19/01; G01S19/03; G01S19/09; G01S19/13; G01S19/24; G01S19/25; G01S19/256; G01S19/258; G04; G04R; G04R20/00; G04R20/02; G04R20/06; G01S19/23; G01S19/235
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
92 words
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.
Claim 2
Dependent Claim
92 words
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.
Claim 3
Dependent Claim
22 words
A computer readable storage medium as in claim 1 wherein said method is performed exclusively at said entity which is a basestation.
Claim 4
Dependent Claim
21 words
A computer readable storage medium as in claim 2 wherein said remote entity is a mobile satellite positioning system (SPS) receiver.
Claim 5
Dependent Claim
18 words
A computer readable storage medium as in claim 3 wherein said mobile SPS receiver is a GPS receiver.
Claim 6
Dependent Claim
29 words
A computer readable storage medium as in claim 3 wherein said second record provides time of day information such that said time may be determined from said second record.
Claim 7
Dependent Claim
18 words
A computer readable storage medium as in claim 5 wherein said second record is stored at said basestation.
Claim 8
Dependent Claim
28 words
A computer readable storage medium as in claim 5 wherein said comparing comprises performing a cross-correlation or a sample-by-sample comparison between said first record and said second record.
Claim 9
Dependent Claim
25 words
A computer readable storage medium as in claim 7, said method further comprising receiving at said entity a plurality of pseudoranges from said remote entity.
Claim 10
Dependent Claim
30 words
A computer readable storage medium as in claim 8, said method further comprising: using said time and said plurality of pseudoranges to determine a position information of said remote entity.
Claim 11
Dependent Claim
17 words
A computer readable storage medium as in claim 5 wherein said first record comprises 50 baud data.
Claim 12
Dependent Claim
22 words
A computer readable storage medium as in claim 5, said method further comprising precisely determining a carrier frequency of said first record.
Claim 13
Dependent Claim
20 words
A computer readable storage medium as in claim 9, said method further comprising communicating said position information to another entity.
Claim 14
Dependent Claim
23 words
A computer readable storage medium as in claim 6 wherein said first record is not demodulated and said basestation demodulates said first record.
Claim 15
Dependent Claim
38 words
A computer readable storage medium as in claim 1 wherein said first record comprises at least one record of at least said portion of said satellite data message corresponding to a first pseudorange of said plurality of pseudoranges.
Claim 16
Dependent Claim
94 words
A computer readable storage medium as in claim 14 further comprising: receiving at said entity a third record of at least a portion of a second satellite data message; comparing said third record with a fourth record of said second satellite data message, wherein said third record and said fourth record overlap at least partially in time; determining a second time from said comparing, said second time indicating when said third record was received at said remote entity, wherein said second satellite data message corresponds to a second pseudorange of said plurality of pseudoranges.
Claim 17
Dependent Claim
32 words
A computer readable storage medium as in claim 1 wherein said remote entity is a cellular telephone and said first record is received from said cellular telephone through a cellular telephone site.
Claim 18
Dependent Claim
20 words
A computer readable storage medium as in claim 16, said method further comprising communicating said position information to another entity.
Claim 19
Dependent Claim
23 words
A computer readable storage medium as in claim 17 wherein said another entity comprises a system coupled to said entity through a network.
Claim 20
Dependent Claim
101 words
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.
Claim 21
Dependent Claim
101 words
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.
Claim 22
Dependent Claim
29 words
A processor readable storage medium as in claim 19 wherein said second record provides time of day information such that said time may be determined from said second record.
Claim 23
Dependent Claim
18 words
A processor readable storage medium as in claim 20 wherein said second record is received from a basestation.
Claim 24
Dependent Claim
22 words
A processor readable storage medium as in claim 21, said method further comprising receiving satellite ephemeris information at said mobile SPS receiver.
Claim 25
Dependent Claim
19 words
A processor readable storage medium as in claim 22 wherein said satellite ephemeris information is received from said basestation.
Claim 26
Dependent Claim
22 words
A processor readable storage medium as in claim 20, said method further comprising receiving SPS signals and determining a plurality of pseudoranges.
Claim 27
Dependent Claim
25 words
A processor readable storage medium as in claim 24 wherein said first record is obtained by removing a PN code from said satellite data message.
References Cited (Backward Citations)
US4445118A
Cited
US4449830A
Cited
US4734701A
Cited
EP0444738A2
Cited
US5117232A
Cited
EP0508405A1
Cited
US5225842A
Cited
EP0545636A1
Cited
US5379224A
Cited
US5317322A
Cited
US5319374A
Cited
US5317323A
Cited
US5420592A
Cited
US5510797A
Cited
US5521887A
Cited
US5625556A
Cited
GB2301725A
Cited
US5640442A
Cited
US5570097A
Cited
US5841026A
Cited
US5812087A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-04-18 | 2003-10-18 | 2004-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-04-18 | 2007-10-18 | 2008-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-04-18 | 2011-10-18 | 2012-04-18 | $7700.00 | Window Closed / Lapsed |