Parallel cell ID acquisition in frequency division multiple access systems

• US 7,620,029 B2
• Filed: 10/09/2003
• Issued: 11/17/2009
• Est. Priority Date: 10/09/2003
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Pandian, David, Rick, Roland
• Primary Examiner(s): Vuong; Quochien B
• Application Number:
  US10/683,640
• Publication Number:
  US 20050078654A1
• Time in Patent Office: 2,231 Days
• Field of Search: 370/319, 370/328, 370/329, 370/331, 370/332, 370/344, 455/436, 455/450, 455/500, 455/502, 455/509, 455/515, 455/516, 455/524, 455/525, 375/356
• US Class Current: 370/344
• CPC Class Codes: H04B 7/2681 Synchronisation of a mobile station with one base station
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 56/00 Synchronisation arrangements

Abstract

This disclosure is directed to cell acquisition techniques for telecommunication systems that implement FDMA and TDMA techniques, such as GSM systems. The techniques make efficient use of processing time in order to accelerate the cell acquisition process. Upon acquiring synchronization information of a first cell of an FDMA system, the timing for the acquisition of cell identification (ID) information associated with the first cell can be scheduled based on the synchronization information of the first cell. Synchronization information of a second cell of the FDMA system can then be acquired prior to acquiring the cell ID information associated with the first cell. Moreover, synchronization information of a additional cells may similarly be acquired prior to acquiring the cell ID information associated with the first cell. In this manner, efficient use of processing time can be achieved between the acquisition of synchronization information and the acquisition of cell ID information.

Claims

1. A method comprising:

acquiring synchronization information of a first cell of a wireless communication system;

scheduling time for acquisition of cell identification (ID) information associated with the first cell based on the synchronization information of the first cell; and

acquiring synchronization information of a second cell of the wireless communication system after acquiring the synchronization information of the first cell and prior to acquiring the cell ID information associated with the first cell.

2. The method of claim 1, further comprising acquiring the synchronization information of the second cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell only when enough time exists for acquiring the synchronization information of the second cell before the scheduled time for acquisition of cell ID information associated with the first cell.

3. The method of claim 1, further comprising:

scheduling time for acquisition of cell ID information associated with the second cell based on the synchronization information of the second cell; and

acquiring synchronization information of a third cell of the wireless communication system prior to acquiring the cell ID information associated with the second cell.

4. The method of claim 3, further comprising acquiring synchronization information of the third cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell.

5. The method of claim 1, further comprising acquiring the cell ID information associated with the first cell at the scheduled time following the acquisition of synchronization information of the second cell.

6. The method of claim 5, further comprising selecting or rejecting the first cell based on the cell ID information associated with the first cell.

7. The method of claim 6, further comprising registering in the first cell when the first cell is selected based on the cell ID information associated with the first cell.

8. The method of claim 1, wherein the wireless communication system comprises a global systems for mobile communications (GSM) system, acquiring the synchronization information includes acquiring a frequency correction channel (FCCH) and a synchronization channel (SCH), and acquiring the cell ID information includes acquiring a public land mobile network (PLMN) code from a broadcast channel (BCCH).

9. The method of claim 1, further comprising generating a list of available networks including the first cell and the second cell, based on the cell ID information associated with the first cell and cell ID information associated with the second cell.

10. A subscriber unit comprising:

a receiver to receive a first signal associated with a first cell of a wireless communication system and a second signal associated with a second cell of the wireless communication system; and

a control unit to acquire synchronization information of the first cell, schedule time for acquisition of cell identification (ID) information associated with the first cell based on the synchronization information of the first cell, and acquire synchronization information of the second cell after acquiring the synchronization information of the first cell and prior to acquiring the cell ID information associated with the first cell.

11. The subscriber unit of claim 10, wherein the control unit acquires the synchronization information of the second cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell only when enough time exists for acquiring the synchronization information of the second cell before the scheduled time for acquisition of cell ID information associated with the first cell.

12. The subscriber unit of claim 10, wherein the control unit schedules time for acquisition of cell ID information associated with the second cell based on the synchronization information of the second cell, and acquires synchronization information of a third cell of the wireless communication system prior to acquiring the cell ID information associated with the second cell.

13. The subscriber unit of claim 12, wherein the control unit acquires synchronization information of the third cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell.

14. The subscriber unit of claim 10, wherein the control unit acquires the cell ID information associated with the first cell at the scheduled time.

15. The subscriber unit of claim 14, wherein the control unit selects or rejects the first cell based on the cell ID information associated with the first cell.

16. The subscriber unit of claim 10, wherein the control unit causes the subscriber unit to register in the first cell when the first cell is selected based on the cell ID information associated with the first cell.

17. The subscriber unit of claim 10, wherein the wireless communication system comprises a global systems for mobile communications (GSM) system, acquiring the synchronization information includes acquiring a frequency correction channel (FCCH) and a synchronization channel (SCH), and acquiring the cell ID information includes acquiring a public land mobile network (PLMN) code from a broadcast channel (BCCH).

18. A computer-readable medium stored with instructions executable by a subscriber unit, the instructions to cause the subscriber unit to:

acquire synchronization information of a first cell of a wireless communication system;

schedule time for acquisition of cell identification (ID) information associated with the first cell based on the synchronization information of the first cell; and

acquire synchronization information of a second cell of the wireless communication system after acquiring the synchronization information of the first cell and prior to acquiring the cell ID information associated with the first cell.

19. The computer-readable medium of claim 18, further comprising instructions that cause the subscriber unit to acquire the synchronization information of the second cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell only when enough time exists for acquiring the synchronization information of the second cell before the scheduled time for acquisition of cell ID information associated with the first cell.

20. The computer-readable medium of claim 18, further comprising instructions that cause the subscriber unit to schedule time for acquisition of cell ID information associated with the second cell based on the synchronization information of the second cell, and acquire synchronization information of a third cell of the wireless communication system prior to acquiring the cell ID information associated with the second cell.

21. The computer-readable medium of claim 20, further comprising instructions that cause the subscriber unit to acquire synchronization information of the third cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell.

22. The computer-readable medium of claim 18, further comprising instructions that cause the subscriber unit to acquire the cell ID information associated with the first cell at the scheduled time.

23. The computer-readable medium of claim 22, further comprising instructions that cause the subscriber unit to select or reject the first cell based on the cell ID information associated with the first cell.

24. The computer-readable medium of claim 23, further comprising instructions that cause the subscriber unit to register in the first cell when the first cell is selected based on the cell ID information associated with the first cell.

25. The computer-readable medium of claim 18, wherein the wireless communication system comprises a global systems for mobile communications (GSM) system, acquiring the synchronization information includes acquiring a frequency correction channel (FCCH) and a synchronization channel (SCH), and acquiring the cell ID information includes acquiring a public land mobile network (PLMN) code from a broadcast channel (BCCH).

26. A subscriber unit comprising:

means for acquiring synchronization information of a first cell of a wireless communication system;

means for scheduling time for acquisition of cell identification (ID) information associated with the first cell based on the synchronization information of the first cell; and

means for acquiring synchronization information of a second cell of the wireless communication system after acquiring the synchronization information of the first cell and prior to acquiring the cell ID information associated with the first cell.

27. The subscriber unit of claim 26, further comprising means for acquiring the synchronization information of the second cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell only when enough time exists for acquiring the synchronization information of the second cell before the scheduled time for acquisition of cell ID information associated with the first cell.

28. The subscriber unit of claim 26, further comprising:

means for scheduling time for acquisition of cell ID information associated with the second cell based on the synchronization information of the second cell; and

means for acquiring synchronization information of a third cell of the wireless communication system prior to acquiring the cell ID information associated with the second cell.

29. The subscriber unit of claim 28, farther comprising means for acquiring synchronization information of the third cell of the wireless communication system prior to acquiring the cell ID information associated with the first cell.

30. The subscriber unit of claim 26, further comprising means for acquiring the cell ID information associated with the first cell at the scheduled time.

31. The subscriber unit of claim 30, further comprising means for selecting or rejecting the first cell based on the cell ID information associated with the first cell.

32. The subscriber unit of claim 31, farther comprising means for registering in the first cell when the first cell is selected based on the cell ID information associated with the first cell.

33. The subscriber unit of claim 26, wherein the wireless communication system comprises a global systems for mobile communications (GSM) system, acquiring the synchronization information includes acquiring a frequency correction channel (FCCH) and a synchronization channel (SCH), and acquiring the cell ID information includes acquiring a public land mobile network (PLMN) code from a broadcast channel (BCCH).

34. In a global systems for mobile communications (GSM) system, a method comprising:

acquiring a frequency correction channel (FCCH) and a synchronization channel (SCH) of a first cell;

scheduling time for decoding of a broadcast channel (BCCH) associated with the first cell based on SCH of the first cell; and

acquiring an FCCH and an SCH of a second cell after acquiring the FCCH and the SCH of the first cell and prior to decoding the BCCH associated with the first cell.

35. The method of claim 34, further comprising acquiring the FCCH and SCH of the second cell prior to decoding the BCCH associated with the first cell only when enough time exists for acquiring the FCCH and SCH of the second cell before the scheduled time for acquisition of BCCH associated with the first cell.

36. The method of claim 34, wherein decoding the BCCH associated with the first cell includes acquiring a public land mobile network (PLMN) code for the first cell from the BCCH associated with the first cell.

37. The method of claim 34, further comprising:

scheduling time for decoding of a BCCH associated with the second cell prior to the decoding of the BCCH associated with the first cell.