Wireless terminal location using apparatus and methods employing carrier diversity

1. A method for use with a wireless device, the method comprising:

receiving from a first base station a first plurality of signals corresponding to different carrier frequencies, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability;

receiving at least a second signal from a second base station, said first and second signals corresponding to first and second carrier frequencies, respectively, said first and second carrier frequencies being different;

determining at least two channel gain ratios based, at least in part, on information indicative of corresponding predetermined relative transmission powers of said first and second signals, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station; and

determining a geographic area location estimate based, at least in part, on geographic location information which corresponds to said at least two determined channel gain ratios.

2. The method of claim 1 , wherein said one of said first plurality of signals comprises a strongest one of said first plurality of signals.

3. The method of claim 1 , wherein receiving said second signal further comprises:

receiving from said second base station a second plurality of signals corresponding to different carrier frequencies; and

selecting a strongest one of said second plurality of signals as said second signal.

4. The method of claim 3 , wherein at least two of said second plurality of signals are transmitted at different power levels.

5. The method of claim 1 , further comprising:

obtaining said information indicative of corresponding relative transmission powers of at least said first and second signals.

6. The method of claim 5 further comprising:

receiving broadcast information associated with a transmission power level used by said first base station for at least said first signal; and

receiving broadcast information associated with a transmission power level used by said second base station for at least said second signal.

7. The method of claim 1 , wherein determining said geographic area location estimate further comprises:

transmitting at least said at least two determined channel gain ratios to a network node; and

in response, receiving from said network node information associated with said geographic area location estimate.

8. The method of claim 1 , wherein said first and second signals comprise orthogonal frequency division multiplexing (OFDM) signals.

9. A wireless device comprising:

a receiver to receive a plurality of signals comprising at least: from a first base station a first plurality of signals corresponding to different carrier frequencies, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability, and from a second base station a second signal, said first and second signals corresponding to first and second carrier frequencies respectively, said first and second carrier frequencies being different;

a power measurement module to measure a corresponding received power of said first and second signals;

a relative transmission power determination module to determine relative transmission powers between said first and second signals;

a channel gain ratio module to determine at least two channel gain ratios based, at least in part, on information indicative of corresponding predetermined relative transmission powers of said first and second signals, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station; and

a geographic area determination module to determine a geographic area location estimate for said wireless device based, at least in part, on geographic location information corresponding to said at least two determined channel gain ratios.

10. The wireless device of claim 9 , further comprising:

a selection module to select said first and second signals from among said received plurality of signals.

11. The wireless device of claim 10 , said selection module to select at least one of said first and second signals based, at least in part, on a received signal strength.

12. The wireless device of claim 9 , said receiver to receive broadcast information based upon the transmitted first and second gain ratios.

13. The wireless device of claim 9 , further comprising:

memory to store base station location information, and said received first and second signals comprising OFDM beacon signals.

14. The wireless device of claim 9 , further comprising:

a transmitter to transmit first and second channel gain ratios to a base station over an uplink wireless communications channel, and wherein

said receiver to receive said geographic location information based, at least in part, on said transmitted first and second gain ratios.

15. The wireless device of claim 9 , further comprising:

memory to store base station location information, and wherein

said geographic area determination module to determine said geographic area location estimate based further, at least in part, on said base station location information.

16. A method for use with a wireless device, the method comprising:

receiving from a first base station a first plurality of signals corresponding to different carrier frequencies, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability;

receiving at least a second signal from a second base station, said first and second signals corresponding to first and second carrier frequencies, respectively, said first and second carrier frequencies being different;

determining at least two channel gain ratios, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station, said first channel gain ratio comprising a ratio of a first channel gain to a second channel gain, said first channel gain comprising a channel gain between said first base station and said wireless device, said second channel gain comprising a channel gain between said second base station and said wireless device; and

determining a geographic area location estimate based, at least in part, on geographic location information which corresponds to said at least two determined channel gain ratios.

17. A wireless device comprising:

a receiver to receive a plurality of signals comprising at least: from a first base station a first plurality of signals corresponding to different carrier frequencies, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability, and from a second base station a second signal, said first and second signals corresponding to first and second carrier frequencies respectively, said first and second carrier frequencies being different;

a power measurement module to measure a corresponding received power of said first and second signals;

a relative transmission power determination module to determine relative transmission powers between said first and second signals;

a channel gain ratio module to determine at least two channel gain ratios, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station, said first channel gain ratio comprising a ratio of a first channel gain to a second channel gain, said first channel gain comprising a channel gain between said first base station and said wireless device, said second channel gain comprising a channel gain between said second base station and said wireless device; and

a geographic area determination module to determine a geographic area location estimate for said wireless device based, at least in part, on geographic location information corresponding to said at least two determined channel gain ratios.

18. An apparatus for use in a wireless device, the apparatus comprising:

means for receiving a plurality of signals comprising: from a first base station a first plurality of signals corresponding to different carrier frequencies, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability; and from a second base station a second signal, said first and second signals corresponding to first and second carrier frequencies, respectively, said first and second carrier frequencies being different; and

means for determining at least two channel gain ratios based, at least in part, on information indicative of corresponding predetermined relative transmission powers of said first and second signals, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station; and

means for determining a geographic area location estimate for said wireless device based, at least in part, on geographic location information which corresponds to said at least two determined channel gain ratios.

19. The apparatus of claim 18 , wherein said one of said first plurality of signals comprises a strongest one of said first plurality of signals.

20. The apparatus of claim 18 , further comprising:

means for receiving, from said second base station, a second plurality of signals corresponding to different carrier frequencies; and

means for selecting a strongest one of said second plurality of signals as said second signal.

21. The apparatus of claim 20 , wherein at least two of said second plurality of signals are transmitted at different power levels.

22. The apparatus of claim 18 , further comprising:

means for obtaining said information indicative of corresponding relative transmission powers of at least said first and second signals.

23. The apparatus of claim 22 , further comprising:

means for receiving broadcast information associated with a transmission power level used by said first base station for at least said first signal; and

means for receiving broadcast information associated with a transmission power level used by said second base station for at least said second signal.

24. The apparatus of claim 18 , further comprising:

means for transmitting at least said at least two determined channel gain ratios to a network node; and

means for receiving, from said network node, information associated with said geographic area location estimate.

25. The apparatus of claim 18 , wherein said first and second signals comprise orthogonal frequency division multiplexing (OFDM) signals.

26. An apparatus for use in a wireless device, the apparatus comprising:

means for receiving a plurality of signals comprising: from a first base station a first plurality of signals corresponding to different carrier frequencies, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability; and from a second base station a second signal, said first and second signals corresponding to first and second carrier frequencies, respectively, said first and second carrier frequencies being different; and

means for determining at least two channel gain ratios, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station, said first channel gain ratio comprising a ratio of a first channel gain to a second channel gain, said first channel gain comprising a channel gain between said first base station and said wireless device, said second channel gain comprising a channel gain between said second base station and said wireless device; and

means for determining a geographic area location estimate for said wireless device based, at least in part, on geographic location information which corresponds to said at least two determined channel gain ratios.

27. An article comprising:

a non-transitory data storage medium having stored thereon a plurality of computer implementable instructions implementable by a processor in a wireless device to:

obtain a plurality of signals comprising: a first plurality of signals corresponding to different carrier frequencies received from a first base station, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein, one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability; and a second signal from a second base station, said first and second signals corresponding to first and second carrier frequencies, respectively, said first and second carrier frequencies being different; and

determine at least two channel gain ratios based, at least in part, on information indicative of corresponding predetermined relative transmission powers of said first and second signals, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station;

obtain on geographic location information which corresponds to said at least two determined channel gain ratios; and

determine a geographic area location estimate for said wireless device based, at least in part, on said geographic location information.

28. The article of claim 27 , said computer implementable instructions being further implementable to select said first and second signals from among said received plurality of signals.

29. The article of claim 28 , said computer implementable instructions being further implementable to select at least one of said first and second signals based, at least in part, on a received signal strength.

30. The article of claim 27 , said computer implementable instructions being further implementable to obtain broadcast information including at least one of a base station transmission power level and a base station relative transmission power level.

31. The article of claim 27 , said received first and second signals comprising OFDM beacon signals.

32. The article of claim 27 , said computer implementable instructions being further implementable to:

initiate transmission of first and second channel gain ratios to a base station over an uplink wireless communications channel.

33. The article of claim 27 , said computer implementable instructions being further implementable to:

obtain at least a portion of said geographic location information from a base station.

34. The article of claim 27 , said computer implementable instructions being further implementable to:

obtain base station location information; and

determine said geographic area location estimate based further, at least in part, on said base station location information.

35. An article comprising:

a non-transitory data storage medium having stored thereon a plurality of computer implementable instructions implementable by a processor in a wireless device to:

obtain a plurality of signals comprising: a first plurality of signals corresponding to different carrier frequencies received from a first base station, wherein at least two of said first plurality of signals are transmitted at different power levels, and wherein one of said first plurality of signals is selected as a first signal based, at least in part, on an indication of received signal reliability; and a second signal from a second base station, said first and second signals corresponding to first and second carrier frequencies, respectively, said first and second carrier frequencies being different; and

determine at least two channel gain ratios, said at least two channel gain ratios comprising a first channel gain ratio associated with said first base station and a second channel gain ratio associated with said second base station, said first channel gain ratio comprising a ratio of a first channel gain to a second channel gain, said first channel gain comprising a channel gain between said first base station and said wireless device, said second channel gain comprising a channel gain between said second base station and said wireless device;

obtain on geographic location information which corresponds to said at least two determined channel gain ratios; and

determine a geographic area location estimate for said wireless device based, at least in part, on said geographic location information.