Subscriber station with dynamic multi-mode service acquisition capability

1. A system for providing a dynamic multi-mode service acquisition capability to a subscriber station, the subscriber station capable of operating in two or more modes of operation, the system comprising:

first logic for indicating a time to scan condition while the subscriber station is operating in a current mode of operation having active and inactive states, the time to scan condition is indicated responsive to sufficient proximity being detected between the subscriber station and coverage area of a candidate system, wherein the proximity detection is accomplished based on consideration of an estimated location of the subscriber station in relation to the coverage area of the candidate system;

second logic for, responsive to the first logic, indicating a time to scan condition storing state information for the current mode of operation and attempting at least a partial acquisition of communications services from a candidate system in accordance with another mode of operation, the at least partial acquisition attempt initiated while the subscriber station is in the inactive state in the current mode of operation and scheduled to be accomplished before the subscriber station transitions back to the active state in the current mode of operation; and

third logic for, if the at least partial acquisition attempt is successful, causing the subscriber station to cease operating in accordance with the current mode of operation and begin operating in accordance with the other mode of operation, and for, if the at least partial acquisition attempt is unsuccessful, allowing the subscriber station to use the stored state information to resume operating in the current mode of operation.

2. The system of claim 1 wherein the estimated location of the subscriber station is determined based on signals received from one or more reference sources.

3. The system of claim 1 wherein at least one of the reference sources comprises a GPS satellite.

4. The system of claim 1 wherein at least one of the reference sources is a base station or sector.

5. The system of claim 1 wherein at least one of the reference sources is a GSP satellite and another is a base station or sector.

6. A system for providing a dynamic multi-mode service acquisition capability to a subscriber station, the subscriber station capable of operating in two or more modes of operation, the system comprising:

first logic for indicating a time to scan condition while the subscriber station is operating in a current mode of operation having active and inactive states;

second logic for, responsive to the first logic indicating a time to scan condition, storing state information for the current mode of operation and attempting at least a partial acquisition of communications services in accordance with another mode of operation, the at least partial acquisition attempt initiated while the subscriber station is in the inactive state in the current mode of operation and scheduled to be accomplished before the subscriber station transitions back to the active state in the current mode of operation, wherein the second logic determines when the subscriber station is scheduled to next transition to the active state in the current mode of operation, and, responsive thereto, determines one or more parameters of the at least partial acquisition; and

third logic for, if the at least partial acquisition attempt is successful, causing the subscriber station to cease operating in accordance with the current mode of operation and begin operating in accordance with the other mode of operation and for, if the at least partial acquisition attempt is unsuccessful, allowing the subscriber station to use the stored state information to resume operating in the current mode of operation.

7. The system of claim 6 wherein the one or more parameters comprise coherent integration time.

8. The system of claim 6 wherein the one or more parameters comprise incoherent integration times.

9. The system of claim 6 wherein the one or more parameters comprise coherent and incoherent integration times.

10. The system of claim 6 wherein the one or more parameters comprise one or more energy levels.

11. A method of dynamically acquiring services in a subscriber station, the subscriber station capable of operating in two or more modes of operation, the method comprising:

indicating a time to scan condition while the subscriber station is operating in a current mode of operation having active and inactive states, wherein the time to scan condition is indicated responsive to sufficient proximity being detected between the subscriber station and a coverage area of a candidate system, and wherein the proximity detection is accomplished based on consideration of an estimated location of the subscriber station cell in relation to the coverage area of the candidate system;

storing, responsive to the indication of the time to scan condition, state information for the current mode of operation;

attempting responsive to the indication of the time to scan condition, at least a partial acquisition of communications services in accordance with the other mode of operation, the at least partial acquisition attempt scheduled to be initiated while the subscriber station is in the inactive state in the current mode of operation and completed before the subscriber station transitions back to the active state in the current mode of operation;

causing, if the at least partial acquisition attempt is successful, the subscriber station to cease operating in accordance with the current mode of operation and begin operating in accordance with the other mode of operation; and

allowing, if the at least partial acquisition attempt is unsuccessful, the subscriber station to resume operating in the current mode of operation using the stored state information.

12. The method of claim 11 wherein the estimated location of the subscriber station is determined based on one or more signals received from reference sources.

13. The method of claim 12 wherein at least one of the reference sources comprises a GPS satellite.

14. The method of claim 12 wherein at least one of the reference sources comprises a base station or sector.

15. The method of claim 12 wherein at least one of the reference sources comprises a GPS satellite and another comprises a base station or sector.

16. The method of claim 11 wherein the attempting step comprises correlating a received signal with an identification code uniquely identifying a candidate system, resulting in a correlation function having a peak, and determining if the peak of the correlation function exceeds a predetermined threshold.

17. The method of claim 11 further comprising determining when the subscriber station is scheduled to transition to the active state in the current mode of operation, and, responsive thereto, determining one or more parameters of the at least partial acquisition.

18. The method of claim 17 wherein the one or more parameters comprise coherent integration time.

19. The method of claim 17 wherein the one or more parameters comprise non-coherent integration time.

20. The method of claim 17 wherein the one or more parameters comprise coherent and incoherent integration times.

21. The method of claim 17 wherein the one or more parameters comprise one or more energy levels.