Satellite (GPS) assisted clock apparatus, circuits, systems and processes for cellular terminals on asynchronous networks

• US 8,249,616 B2
• Filed: 08/23/2007
• Issued: 08/21/2012
• Est. Priority Date: 08/23/2007
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Boejer, Joergen, Vallauri, Alain, Guvelioglu, Ilyas Berk
• Primary Examiner(s): Patel, Ajit
• Assistant Examiner(s): WYCHE, MYRON
• Application Number:
  US11/844,006
• Publication Number:
  US 20090054075A1
• Time in Patent Office: 1,825 Days
• Field of Search: 455/33.1, 455/65, 455/272, 455/456.1, 455/456.21, 455/456.3, 455/456.4, 455/456.5, 455/456.6, 455/502, 455/517, 455/259
• US Class Current: 455/456.1
• CPC Class Codes: G01S 19/09 providing processing capability normally carried out by the receiver
• CPC Class Codes: G01S 19/12 wherein the cooperating elements are telecommunication base stations
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 2205/008 using a mobile telephone network
• CPC Class Codes: H04B 7/18532 Arrangements for managing transmission, i.e. for transporting data or a signalling message

Abstract

A wireless circuit (1100, 1190) for tracking an incoming signal and for use in a network (2000) having handover from one part (Cell A) of the network to another part (Cell B). The wireless circuit includes a processor (CE 1100) responsive to the incoming signal, the processor (CE 1100) operable to generate pulse edges representing network-based receiver synchronization instances (RSIs), and a timekeeping circuitry (2420, 2430, 2450) including an oscillator circuitry (2162), the timekeeping circuitry (2420, 2430) operable to maintain a set of counter circuitries (2422-2428) including a counter circuitry (2422) operable to maintain at least one network time component based on the RSIs and another counter circuitry (2428) operable at least during handover and during loss of network coverage for maintaining at least one internal time component (NC) based on the oscillator circuitry (2162), the set of counter circuitries (2422-2428) operable to account for elapsing time substantially gaplessly and substantially without overlap between the time components during a composite of network coverage, loss of network coverage and handover, and the timekeeping circuitry further including a time generator (2450) for combining the time components from the set of counter circuitries (2422-2428) to generate an approximate absolute time (SGTB). Other electronic circuits, positioning systems, methods of operation, and processes of manufacture are also disclosed and claimed.

Claims

1. A wireless circuit for tracking an incoming signal and for use in a network having handover from one part of the network to another part, and comprising:

a processor responsive to the incoming signal, said processor operable to generate pulse edges representing network-based receiver synchronization instances (RSIs); and

a timekeeping circuitry including an oscillator circuitry, said timekeeping circuitry operable to maintain a set of counter circuitries including a counter circuitry operable to maintain a running count representing at least one network time component based on successive RSIs and another counter circuitry operable at least during handover and during loss of network coverage between the wireless circuit and the network for maintaining a running count for representing at least one internal time component based on the oscillator circuitry, the set of counter circuitries operable to account for elapsing time substantially gaplessly and substantially without overlap between the time components during a composite of network coverage, loss of network coverage and handover, and said timekeeping circuitry further including a time generator for combining the time components from the set of counter circuitries to generate an approximate absolute time.

11. The wireless circuit claimed in claim 1 wherein said oscillator circuitry is adjustable in frequency in response to the incoming signal to provide a frequency correction.

12. The wireless circuit claimed in claim 1 further comprising a power management circuit, and wherein said oscillator circuitry includes an on-clock oscillator and a sleep clock oscillator coupled to said power management circuit.

13. The wireless circuit claimed in claim 1 wherein said oscillator circuitry includes an on-clock oscillator and a sleep clock oscillator coupled to respectively contribute to the set of counter circuitries so that said on-clock oscillator contributes in an awake mode, and said sleep clock oscillator contributes in a sleep mode.

14. The wireless circuit claimed in claim 1 wherein said oscillator circuitry includes an on-clock oscillator and a sleep clock oscillator, and said set of counter circuitries includes a counter responsive to both said on-clock oscillator and a sleep clock oscillator and operable to count a number of on-clock cycles in a sleep clock cycle.

15. The wireless circuit claimed in claim 14 wherein said time generator is responsive to both the time components from the set of counter circuitries and a count from said counter related to number of on-clock cycles in a sleep clock cycle, to generate the approximate absolute time.

16. The wireless circuit claimed in claim 1 wherein said oscillator circuitry includes an on-clock oscillator and a sleep clock oscillator, and said set of counter circuitries includes a further counter responsive to both said on-clock oscillator and said sleep clock oscillator and operable to count a first number of on-clock cycles in a sleep clock cycle prior to a transition from an awake mode to a sleep mode, and said further counter operable to count a second number of on-clock cycles in a sleep clock cycle subsequent to a transition from a sleep mode to an awake mode.

17. The wireless circuit claimed in claim 1 wherein said oscillator circuitry includes an on-clock oscillator, and said set of counter circuitries includes a counter for counting a number related to number of on-clock cycles between RSIs.

18. The wireless circuit claimed in claim 17 wherein said time generator is responsive to the time components from the set of counter circuitries and a count from said counter related to number of on-clock cycles between RSIs, to generate the approximate absolute time.

19. The wireless circuit claimed in claim 1 wherein said time generator is operable to form a ratio responsive to said set of counter circuitries, to contribute to the approximate absolute time.

20. The wireless circuit claimed in claim 1 wherein said time generator is operable to perform an interpolation responsive to said set of counter circuitries, to contribute to the approximate absolute time.

21. The wireless circuit claimed in claim 1 wherein said time generator is operable to perform a thermal correction responsive to said set of counter circuitries, to contribute to the approximate absolute time.

2. An electronic circuit for tracking an incoming signal from a first network, and comprising:

a processor responsive to the incoming signal, said processor operable to generate pulse edges representing network-based receiver synchronization instances (RSIs);

oscillator circuitry; and

an adjustment circuit operable to adjust operational frequency of the oscillator circuitry in response to and to correlate with frequency of receiving the network-based RSIs from said processor, said adjustment circuit including;

a time counter circuitry fed from said oscillator circuitry and including a counter operable to maintain a running count representing at least one network time component between successive RSIs; and

another counter circuitry operable at least during handover and during loss of network coverage between the electronic circuit and the first network for maintaining a running count for representing at least one internal time component based on said oscillator circuitry;

the counter circuitries operable to account for elapsing time between the time components during a composite of network coverage, loss of network coverage and handover;

circuitry, responsive in part to at least one running count, for determining elapsed time from a timing associated with a second network that is asynchronous to the first network.

3. The electronic circuit claimed in claim 2 wherein said another counter circuitry is operable to count clocks between RSIs (receiver synchronization instances) whereupon a next RSI initializes the running count in said another counter circuitry again.

4. The electronic circuit claimed in claim 3 wherein said adjustment circuit further includes a register circuit fed by said counter and coupled for actuation by said processor to hold an initial RSI position count upon occurrence of that next RSI from said processor.

5. The electronic circuit claimed in claim 4 wherein said adjustment circuit further includes an arithmetic circuit fed with the initial RSI position count from said register circuit and further fed with a subsequent running count from said counter, said arithmetic circuit operable to generate a difference between the initial RSI position count and the subsequent running count.

6. The electronic circuit claimed in claim 5 wherein said adjustment circuit further includes an accumulator fed with said difference from said arithmetic circuit.

7. The electronic circuit claimed in claim 6 wherein said accumulator is coupled to said processor for actuation of said accumulator when an RSI occurs, said accumulator operable to accumulate both positive and negative values of said difference.

8. The electronic circuit claimed in claim 6 wherein said oscillator circuitry is coupled to said accumulator for frequency correction.

9. The electronic circuit claimed in claim 2 further comprising a satellite positioning receiver coupled to said adjustment circuit.

10. The electronic circuit claimed in claim 2 for use with an incoming signal having modulation and further comprising a radio frequency (RF) section coupled to said oscillator circuitry and operable to heterodyne the incoming signal to baseband to recover the modulation, said processor responsive to the modulation.