Asymmetric forward power control in a CDMA communication

• US 6,304,562 B1
• Filed: 01/21/1998
• Issued: 10/16/2001
• Est. Priority Date: 06/26/1997
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Youngky, Kang, Heewon, Ahn, Jaemin
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Tsegaye, Saba
• Application Number:
  US09/010,213
• Time in Patent Office: 1,364 Days
• Field of Search: 370/328, 370/332, 370/335, 370/341, 370/342, 370/431, 370/441, 370/331, 455/13.4, 455/522
• US Class Current: 370/332
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff

Abstract

In a CDMA communication system, a method and system for controlling forward link power by a mobile station in a handover state. The method and system include transmitting different power control bits to each base station to independently control the transmission power of each base station.

Claims

1. A code division multiple access (CDMA) system comprising:

a multiplicity of base stations operating to produce a combined forward power level, each one of said multiplicity of base stations having a set of power control bits; and

a mobile station in electronic communication with said multiplicity of base stations, said mobile station capable of measuring said combined forward power level, and said mobile station acting to independently adjust the value of each one of said sets of power control bits based upon said combined forward power level.

2. The CDMA system set forth in claim 1, wherein said mobile station compares the combined forward power level to a threshold and adjusts the values of each one of said sets of power control bits to command each one of said multiplicity of base stations to power down if said combined forward power level is greater than the threshold.

3. The CDMA system set forth in claim 1, wherein each one of said multiplicity of base stations has a forward link pilot signal strength, and wherein said mobile station compares the relative levels of each one of said forward link pilot signal strengths to determine which one of said multiplicity of base stations has a maximum forward link pilot signal strength.

4. The CDMA system set forth in claim 3, wherein said mobile station compares the combined forward power level to a threshold and adjusts the value of each one of said sets of power control bits to command selected ones of said multiplicity of base stations to power down and said one of said multiplicity of base stations having the maximum forward link pilot signal strength to power up if said combined forward power level is less than or equal to the threshold.

5. The CDMA system set forth in claim 1, wherein one of said multiplicity of base stations has a maximum forward link pilot signal strength, and wherein said mobile station compares the combined forward power level to a threshold and adjusts the value of each one of said sets of power control bits to command selected ones of said multiplicity of base stations to power down and said one of said multiplicity of base stations having the maximum forward link pilot signal strength to power up if said combined forward power level is less than or equal to the threshold.

6. A code division multiple access (CDMA) system comprising:

a multiplicity of base stations operating to produce a combined forward power level, each one of said multiplicity of base stations being associated with a set of power control bits; and

a mobile station in electronic communication with said multiplicity of base stations, said mobile station configured to independently adjust the value of each one of said sets of power control bits based upon said combined forward power level.

7. The CDMA system set forth in claim 6, wherein said mobile station compares the combined forward power level to a threshold and adjusts the value of each one of said sets of power control bits to command each one of said multiplicity of base stations to power down if said combined forward power level is greater than the threshold.

8. The CDKA system set forth in claim 6, wherein each one of said multiplicity of base stations has a forward link pilot signal strength, and wherein said mobile station compares the relative levels of each one of said forward link pilot signal strengths to determine which one of said multiplicity of base stations has a maximum forward link pilot signal strength.

9. The CDMA system set forth in claim 8, wherein said mobile station compares the combined forward power level to a threshold and adjusts the value of each one of said sets of power control bits to command selected ones of said multiplicity of base stations to power down and said one of said multiplicity of base stations having the maximum forward link pilot signal strength to power up if said combined a forward power level is less than or equal to the threshold.

10. The CDM system set forth in claim 6, wherein one of said multiplicity of base stations has a maximum forward link pilot signal strength, and wherein said mobile station compares the combined forward power level to a threshold and adjusts the value of each one of said sets of power control bits to command selected ones of said multiplicity of base stations to power down and said one of said multiplicity of base stations having the maximum forward link pilot signal strength to power up if said combined forward power level is less than or equal to the threshold.

11. The CDMA system set forth in claim 6, wherein each one of said multiplicity of base stations stores and maintains one of said sets of power control bits.

12. A method of operating a CMA system comprising the steps of:

measuring a combined forward power level of a multiplicity of base stations, each one of said multiplicity of base stations having a set of power control bits;

comparing the combined forward power level to a threshold; and

adjusting the value of each one of said sets of power control bits independently to command each one of said multiplicity of base stations to power down if said combined forward power level is greater than the threshold.

13. A method of operating a CDMA system comprising the steps of:

measuring a combined forward power level of a multiplicity of base stations, each one of said multiplicity of base stations having a set of power control bits and a forward link pilot signal strength;

comparing the combined forward power level to a threshold;

comparing the relative levels of each one of said forward link pilot signal strengths to determine which one of said multiplicity of base stations has a maximum forward link pilot signal strength; and

adjusting the value of each one of said sets of power control bits independently to command selected ones of said multiplicity of base stations to power down and said one of said multiplicity of base stations having a maximum forward link pilot signal strength to power up if said combined forward power level is less than or equal to the threshold.

14. The method of operating a CDMA system as set forth in claim 13, further comprising the step of adjusting the value of each one of said sets of power control bits independently to command each one of said multiplicity of base stations to power down if said combined forward power level is greater than the threshold.

15. A method of operating a code division multiple access (CDMA) system comprising the steps of:

maintaining a multiplicity of base stations operating to produce a combined forward power level, each one of said multiplicity of base stations being associated with a set of power control bits;

maintaining a mobile station in electronic communication with said multiplicity of base stations;

configuring said mobile station to independently adjust the value of each one of said sets of power control bits based upon said combined forward power level; and

adjusting the value of each one of said sets of power control bits based upon said combined forward power level.

16. The method of operating a CDMA system as set forth in claim 15, further comprising the steps of:

comparing the combined forward power level to a threshold; and

adjusting the value of each one of said sets of power control bits to command each one of said multiplicity of base stations to power down if said combined forward power level is greater than the threshold.

17. The method of operating a CDMA system as set forth in claim 15, wherein each one of said multiplicity of base stations has a forward link pilot signal strength, further comprising the step of:

comparing the relative levels of each one of said forward link pilot signal strengths to determine which one of said multiplicity of base stations has a maximum forward link pilot signal strength.

18. The method of operating a CDMA system as set forth in claim 17, further comprising the step of:

comparing the combined forward power level to a threshold and adjusting the value of each one of said sets of power control bits to command selected ones of said multiplicity of base stations to power down and said one of said multiplicity of base stations having the maximum forward link pilot signal strength to power up if said combined forward power level is less than or equal to the threshold.

19. The method of operating a CDMA system as set forth in claim 15, wherein one of said multiplicity of base stations has a maximum forward link pilot signal strength, further comprising the step of:

comparing the combined forward power level to a threshold and adjusting the value of each one of said sets of power control bits to command selected ones of said multiplicity of base stations to power down and said one of said multiplicity of base stations having the maximum forward link pilot signal strength to power up if said combined forward power level is less than or equal to the threshold.

20. The method of operating a CDMA system as set forth in claim 15, further comprising the step of:

storing and maintaining said sets of power control bits within said multiplicity of base stations.