Method and apparatus for cell identification for uplink interference avoidance using inter-frequency measurements

1. An apparatus operable in a cell employing a downlink carrier configured to:

perform a first inter-frequency measurement on another downlink carrier at a different frequency than said downlink carrier, wherein said first inter-frequency measurement comprises at least one of a receive signal strength indicator (RSSI) measurement, a receive signal code power (RSCP) measurement, and an average channel power-to-total signal power ratio (Ec/Io) measurement;

compare a result of said first inter-frequency measurement of said another downlink carrier with another value; and

perform a second inter-frequency measurement different from said first inter-frequency measurement on said another downlink carrier when said result exceeds said another value to identify another cell from a plurality of co-sited cells, wherein said another downlink carrier of one of said plurality of co-sited cells is skipped and another one of said plurality of co-sited cells is identified based on said second inter-frequency measurement.

2. The apparatus as recited in claim 1 wherein said apparatus is further configured to launch one of an inter-frequency handover and an inter-system handover from said downlink carrier to avoid interference in an uplink carrier.

3. The apparatus as recited in claim 1 wherein said apparatus is further configured to identify said another cell from said plurality of co-sited cells by identifying a scrambling code and timing of said plurality of co-sited cells in accordance with at least one of a primary synchronization channel (P-SCH), a secondary synchronized channel (S-SCH), and a primary common pilot channel (P-CPICH).

4. The apparatus as recited in claim 1 wherein one of said downlink carrier and said another downlink carrier is located in one of a core band of frequencies and an extension band of frequencies.

5. The apparatus as recited in claim 1 wherein said another value is one of a threshold value and a value from a measurement of said downlink carrier.

6. The apparatus as recited in claim 1 wherein said another value is one of a predefined value, a value dynamically set as a function of a network operating conditions associated with said apparatus, and a value based on a characteristic of said apparatus.

7. The apparatus as recited in claim 1 wherein said apparatus is further configured to report said value of said first inter-frequency measurement to a network device.

8. The apparatus as recited in claim 1 wherein said apparatus is further configured to identify said another cell from said plurality of co-sited cells in response to instruction from a network device.

9. The apparatus as recited in claim 1 wherein said second inter-frequency measurement is performed by using a compressed mode.

10. The apparatus as recited in claim 1 wherein said apparatus forms at least a part of a mobile device.

11. A method of operating an apparatus operable in a cell employing a downlink carrier, comprising:

performing a first inter-frequency measurement on another downlink carrier at a different frequency than said downlink carrier, wherein said first inter-frequency measurement comprises at least one of a receive signal strength indicator (RSSI) measurement, a receive signal code power (RSCP) measurement, and an average channel power-to-total signal power ratio (Ec/Io) measurement;

comparing a result of said first inter-frequency measurement of said another downlink carrier with another value; and

performing a second inter-frequency measurement different from said first inter-frequency measurement on said another downlink carrier when said result exceeds said another value to identify another cell from a plurality of co-sited cells, wherein said another downlink carrier of one of said plurality of co-sited cells is skipped and another one of said plurality of co-sited cells is identified based on said second inter-frequency measurement.

12. The method as recited in claim 11 further comprising launching one of an inter-frequency handover and an inter-system handover from said downlink carrier to avoid interference in an uplink carrier.

13. The method as recited in claim 1 wherein said performing said second inter-frequency measurement to identify another cell from said plurality of co-sited cells comprises identifying a scrambling code and timing of said plurality of co-sited cells in accordance with at least one of a primary synchronization channel (P-SCH), a secondary synchronized channel (S-SCH), and a primary common pilot channel (P-CPICH).

14. The method as recited in claim 11 wherein one of said downlink carrier and said another downlink carrier is located in one of a core band of frequencies and an extension band of frequencies.

15. The method as recited in claim 11 wherein said another value is one of a threshold value and a value from a measurement of said downlink carrier.

16. The method as recited in claim 11 wherein said another value is one of a predefined value, a value dynamically set as a function of a network operating conditions associated with said apparatus, and a value based on a characteristic of said apparatus.

17. The method as recited in claim 11 further comprising reporting said value of said first inter-frequency measurement to a network device.

18. The method as recited in claim 11 wherein said performing said second inter-frequency measurement to identify another cell from said plurality of co-sited cells is in response to instruction from a network device.

19. The method as recited in claim 11 wherein said second inter-frequency measurement is performed by using a compressed mode.