Claims
- 1. A method for determining the location of a device in a wireless communication system, comprising:
receiving from a transmission source a first signal having included therein transmitted data and a second signal having included therein an identification code assigned to the transmission source; processing the second signal to recover the identification code; and determining a position estimate of the device based on the recovered identification code.
- 2. The method of claim 1, wherein the transmission source is a repeater in the wireless communication system.
- 3. The method of claim 1, wherein the second signal is a spread spectrum signal.
- 4. The method of claim 3, wherein the spread spectrum signal conforms to a CDMA standard.
- 5. The method of claim 4, wherein the spread spectrum signal conforms to IS-95 CDMA standard.
- 6. The method of claim 1, wherein the identification code comprises a pseudo-noise (PN) sequence at a particular offset.
- 7. The method of claim 1, wherein the identification code comprises a plurality of pseudo-noise (PN) sequences.
- 8. The method of claim 7, wherein the plurality of PN sequences are at particular offsets.
- 9. The method of claim 1, wherein the identification code comprises a delayed and attenuated version of the first signal.
- 10. The method of claim 1, wherein the identification code comprises a plurality of delayed and attenuated versions of the first signal and representative of a particular multipath profile.
- 11. The method of claim 1, wherein the identification code comprises a signal transmitted at a frequency different from the frequency of the first signal.
- 12. The method of claim 1, wherein the identification code comprises a signal transmitted at a frequency different from the frequency of the first signal and at a particular transmit offset.
- 13. The method of claim 1, wherein the identification code comprises one or more Gold code sequences.
- 14. The method of claim 13, wherein each Gold code sequence is at a particular offset.
- 15. The method of claim 1, further comprising:
adjusting a set of measurements for position determination in accordance with the recovered identification code.
- 16. The method of claim 1, wherein the position estimate of the device is a particular location within a coverage area of the transmission source.
- 17. The method of claim 16, wherein the position estimate of the device is approximately the center of the coverage area of the transmission source.
- 18. The method of claim 1, wherein the wireless communication system is a CDMA system.
- 19. The method of claim 1, wherein the wireless communication system is a TDMA system.
- 20. The method of claim 2, wherein the second signal is a spread spectrum signal.
- 21. The method of claim 2, wherein the identification code is a pseudo-noise (PN) sequence at a particular offset.
- 22. The method of claim 2, wherein the position estimate of the device is a particular location within a coverage area of the repeater.
- 23. A method for generating a signal suitable for use to estimate the location of a device in a wireless communication system, comprising:
receiving at a transmission source a first signal having included therein transmitted data; generating at the transmission source a second signal having included therein an identification code assigned to the transmission source; combining the first and second signals to provide a combined signal; and transmitting the combined signal from the transmission source.
- 24. The method of claim 23, further comprising:
processing the first signal to recover a timing reference, and wherein the second signal is generated in accordance with the recovered timing reference.
- 25. The method of claim 24, further comprising:
processing the first signal to recover a frequency reference for a carrier signal of the first signal, and wherein the second signal is further generated in accordance with the recovered frequency reference.
- 26. The method of claim 23, wherein the transmission source is a repeater in the communication system.
- 27. The method of claim 26, further comprising:
conditioning the combined signals within a repeater unit, and wherein the conditioned signal from the repeater unit is transmitted from the repeater.
- 28. The method of claim 26, further comprising:
conditioning the first signal within a repeater unit, and wherein the second signal is combined with the conditioned first signal within the repeater unit.
- 29. The method of claim 23, wherein the identification code is a pseudo-noise (PN) sequence at a particular offset.
- 30. The method of claim 29, wherein the offset of the PN sequence used for the identification code is one of a plurality of possible offsets and is reserved for identification of the transmission source.
- 31. The method of claim 29, wherein the timing of the PN sequence used for the identification code is approximately aligned with the timing of a PN sequence used to spread the transmitted data in the first signal.
- 32. The method of claim 23, wherein a carrier frequency of the second signal approximates a carrier frequency of the first signal.
- 33. The method of claim 23, wherein the second signal is a spread spectrum signal.
- 34. The method of claim 23, wherein an amplitude of the second signal is set to a particular level below the amplitude of the first signal.
- 35. The method of claim 23, wherein the wireless communication system is a CDMA system.
- 36. A method for generating a signal suitable for use to estimate the location of a terminal in a wireless communication system, comprising:
receiving and processing at a transmission source a first signal having included therein transmitted data; generating a second signal having included therein an identification code assigned to the transmission source; transmitting the first signal from the transmission source; and transmitting the second signal to a plurality of terminals within the communication system.
- 37. The method of claim 36, wherein the second signal comprises a plurality of signals at different offsets and representative of a particular multipath profile.
- 38. The method of claim 36, wherein the second signal comprises a plurality of pseudo-noise (PN) sequences at a plurality of offsets and representative of a particular multipath profile.
- 39. A method for determining the location of a terminal in a wireless communication system, comprising:
receiving at the terminal an indication for a particular identification code assigned to a transmission source; receiving from the transmission source a first signal having included therein transmitted data and a second signal having included therein the identification code; and processing the second signal to recover the identification code, and wherein the recovered identification code is used to identify the transmission source, and wherein the location of the terminal is estimated based on a position estimate associated with the identification code.
- 40. The method of claim 39, wherein a list of identification codes is included in a neighbor list of codes to be searched.
- 41. The method of claim 39, wherein a list of identification codes is sent to the terminal in response to a call related to position location.
- 42. The method of claim 39, wherein a list of identification codes is broadcast to the terminal via a broadcast channel.
- 43. The method of claim 39, wherein a list of identification codes is sent to the terminal upon request by the terminal.
- 44. A transmission unit in a wireless communication system, comprising:
a first unit operative to receive, condition, and retransmit signals on both forward and reverse links of the communication system; and a second unit coupled to the first unit and including
a first module operative to receive and process a first signal on the forward link having included therein transmitted data, a second module operative to generate a second signal having included therein an identification code assigned to the transmission unit, and a third module operative to combine the first and second signals to provide a combined signal for transmission from the transmission unit.
- 45. The transmission unit of claim 44, wherein the first module is further operative to process the first signal to recover a timing reference, and wherein the second signal is generated in accordance with the recovered timing reference.
- 46. The transmission unit of claim 45, wherein the first module is further operative to process the first signal to recover a frequency reference for a carrier signal of the first signal, and wherein the second signal is further generated in accordance with the recovered frequency reference.
- 47. A communication terminal including:
a receiver capable of receiving signals transmitted by a repeater and signals that were not transmitted by a repeater; and a processor for determining whether received signals were transmitted by a repeater or not, the processor further capable of ensuring that signals received from a repeater not be used in determining the position of the communication terminal.
- 48. A method for preventing signals transmitted through a repeater of a communication system from affecting a position determination, including:
receiving signals transmitted by a repeater and signals that were not transmitted by a repeater; determining whether received signals were transmitted by a repeater or not; and ensuring that signals received from a repeater not be used in determining the position of the communication terminal.
- 49. The method of claim 48, wherein the step of determining whether received signals were transmitted by a repeater or not is made based upon detection of an identification code inserted in the signals by the repeater.
- 50. A method for preventing signals transmitted through a repeater of a communication system from affecting a position determination, including:
receiving signals transmitted by a repeater and signals that were not transmitted by a repeater; transmitting information regarding the received signals, including an identification code which determines whether received signals were transmitted by a repeater or not; and ensuring that information related to signals received from a repeater is not used in determining the position of the communication terminal.
- 51. A method for determining the location of a device in a wireless communication system, comprising:
receiving from a first transmission source a first signal having included therein transmitted data and a second signal having included therein a first identification code assigned to the first transmission source, wherein the first identification code is selected from among a list of identification codes used for nearby transmission sources; processing the second signal to recover the first identification code; and determining a position estimate of the device based on the recovered first identification code.
- 52. The method of claim 51, wherein a determination of whether the first identification code is received from the first transmission source or another transmission source is made based on geometric constraint.
- 53. The method of claim 52, wherein the geometric constraint relates to time difference of arrival (TDOA) measurement.
- 54. The method of claim 51, wherein only identification codes in the list that are not repeated by other transmission sources are available for use as the first identification code for the first transmission source.
- 55. The method of claim 51, wherein the first identification code comprises a plurality of identification codes in the list.
- 56. The method of claim 55, wherein the plurality of identification codes for the first identification code are associated with different offsets.
- 57. The method of claim 51, wherein the nearby transmission sources are neighbor base stations, and the identification codes in the list are PN sequences assigned to the neighbor base stations.
- 58. The method of claim 51, wherein the identification code assigned to the first transmission source is delayed relative to the first signal by a particular amount of delay.
- 59. The method of claim 58, wherein the amount of delay is selected to allow for determination of whether the first identification code is received from the first transmission source or another transmission source.
- 60. A wireless terminal comprising:
a receiver operative to receive from a first transmission source a first signal having included therein transmitted data and a second signal having included therein a first identification code assigned to the first transmission source, wherein the first identification code is selected from among a list of identification codes used for nearby transmission sources; and a processor operative to process the second signal to recover the first identification code, wherein a position estimate of the terminal is determined based on the recovered first identification code.
- 61. The terminal of claim 60, wherein a determination of whether the first identification code is received from the first transmission source or another transmission source is made based on geometric constraint.
- 62. A method for determining the location of a device in a wireless communication system, comprising:
receiving from a transmission source a signal having included therein transmitted data, wherein the signal is further processed based on an identification code assigned to the transmission source; processing the signal to recover the identification code; and determining a position estimate of the device based on the recovered identification code.
- 63. The method of claim 62, wherein the signal is modulated by the identification code.
- 64. The method of claim 62, wherein the identification code is a PN sequence used for transmission source identification.
- 65. The method of claim 62, wherein the identification code is a PN sequence used by another transmission source to spectrally spread data.
- 66. A transmission unit in a wireless communication system, comprising:
a first unit operative to receive and process a first signal having included therein transmitted data, and to generate a second signal having included therein an identification code assigned to the transmission unit, and a second unit coupled to the first unit and operative to receive and modulate the first signal with the second signal to provide a modulated signal for transmission from the transmission unit, and wherein the identification code is used for position determination.
- 67. A wireless terminal comprising:
a receiver operative to receive from a transmission source a first signal having included therein transmitted data, wherein the first signal is further modulated with a second signal having included therein an identification code assigned to the transmission source, and wherein the receiver is further operative to process the first signal to recover the second signal; and a processor operative to process the second signal to recover the identification code, wherein a position estimate of the terminal is determined based on the recovered identification code.
RELATED APPLICATIONS
[0001] This application is a continuation in part of U.S. patent application Ser. No. 09/933,629, filed Aug. 20, 2001, entitled “METHOD AND APPARATUS FOR ESTIMATING THE POSITION OF A TERMINAL BASED ON IDENTIFICATION CODES FOR TRANSMISSION SOURCES,” which is a continuation in part of U.S. patent application Ser. No. 09/904,330, filed Jul. 12, 2001, entitled “METHOD AND APPARATUS FOR ESTIMATING THE POSITION OF A TERMINAL BASED ON IDENTIFICATION CODES FOR TRANSMISSION SOURCES”, all of which claims priority to U.S. Provisional Application No. 60/286,274, filed Apr. 24, 2001 and U.S. Provisional Application No. 60/299,315, filed Jun. 18, 2001.
Provisional Applications (2)
|
Number |
Date |
Country |
|
60286274 |
Apr 2001 |
US |
|
60299315 |
Jun 2001 |
US |
Continuation in Parts (2)
|
Number |
Date |
Country |
Parent |
09933629 |
Aug 2001 |
US |
Child |
10132908 |
Apr 2002 |
US |
Parent |
09904330 |
Jul 2001 |
US |
Child |
09933629 |
Aug 2001 |
US |