Method and system for utilizing polarization reuse in wireless communications

• US 20020164954A1
• Filed: 05/07/2001
• Published: 11/07/2002
• Est. Priority Date: 05/07/2001
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Jalali, Ahmad
• Granted Patent: US 7,493,143 B2
• Time in Patent Office: Days
• US Class Current: 455/67.11
• CPC Class Codes: H04B 7/0491 using two or more sectors, i.e. sector diversity
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

According to a disclosed embodiment, a first plurality of pilot signals of a first polarization is received and ranked. Subsequently, a second plurality of pilot signals of a second polarization is received and ranked. Following, a pilot signal from the first and second pluralities of pilot signals is selected based on a signal quality measurement such as a signal to interference ratio. Moreover, a system can be constructed comprising antennas configured to receive pilot signals of a first and a second polarization. The system further comprises a receiver configured to demodulate the pilot signals and a CPU configured to rank the pilot signals and to select a pilot signal based on a signal quality measurement. Communication quality is improved by communicating with the base transceiver station transmitting the pilot signal providing the highest signal quality measurement.

Claims

1. A method comprising steps of:

receiving a first plurality of pilot signals of a first polarization;

ranking said first plurality of pilot signals;

receiving a second plurality of pilot signals of a second polarization;

ranking said second plurality of pilot signals;

selecting a pilot signal from said first plurality of pilot signals and said second plurality of pilot signals based on a signal quality measurement.

2. The method of claim 1 further comprising a step of demodulating said first plurality of pilot signals after said step of receiving said first plurality of pilot signals and before said step of ranking said first plurality of pilot signals.

3. The method of claim 1 further comprising a step of demodulating said second plurality of pilot signals after said step of receiving said second plurality of pilot signals and before said step of ranking said second plurality of pilot signals.

4. The method of claim 1 wherein said first polarization is orthogonal to said second polarization.

5. The method of claim 1 wherein said first polarization and said second polarization are selected from the group consisting of a vertical polarization and a horizontal polarization.

6. The method of claim 1 wherein said first polarization and said second polarization are selected from the group consisting of a right hand circular polarization and a left hand circular polarization.

7. The method of claim 1 wherein said signal quality measurement comprises a signal to interference ratio.

8. The method of claim 1 wherein said signal quality measurement comprises a signal to noise ratio.

9. The method of claim 1 wherein said step of ranking said first plurality of pilot signals is based on said signal quality measurement.

10. The method of claim 1 wherein said step of ranking said second plurality of pilot signals is based on said signal quality measurement.

11. A method comprising steps of:

measuring a first signal quality of a first plurality of polarized pilot signals received utilizing a first polarized reception system, wherein each pilot signal of said first plurality of polarized pilot signals identifies one of a first plurality of sectors;

measuring a second signal quality of a second plurality of polarized pilot signals received utilizing a second polarized reception system, wherein each pilot signal of said second plurality of polarized pilot signals identifies one of a second plurality of sectors;

selecting a sector from said first plurality of sectors and said second plurality of sectors by comparing said first signal quality with said second signal quality.

12. The method of claim 11 wherein said first plurality of polarized pilot signals is orthogonal to said second plurality of polarized pilot signals.

13. The method of claim 11 wherein said first signal quality is measured by using a signal to interference ratio.

14. The method of claim 11 wherein said second signal quality is measured by using a signal to interference ratio.

15. The method of claim 11 wherein said first signal quality is measured by using a signal to noise ratio.

16. The method of claim 11 wherein said second signal quality is measured by using a signal to noise ratio.

17. The method of claim 11 wherein said selecting step comprises sending a sector identification to a base station.

18. The method of claim 11 wherein said selecting step further comprises steps of:

ranking said first plurality of polarized pilot signals;

ranking said second plurality of polarized pilot signals.

19. The method of claim 18 wherein said step of ranking said first plurality of polarized pilot signals is based on a signal to interference ratio measurement.

20. The method of claim 18 wherein said step of ranking said second plurality of polarized pilot signals is based on a signal to interference ratio measurement.

21. A system comprising:

a first antenna configured to receive a first plurality of pilot signals of a first polarization;

a second antenna configured to receive a second plurality of pilot signals of a second polarization;

a receiver configured to demodulate said first plurality of pilot signals and said second plurality of pilot signals;

a CPU configured to rank said first plurality of pilot signals and said second plurality of pilot signals, said CPU being further configured to select a pilot signal from said first plurality of pilot signals and said second plurality of pilot signals based on a signal quality measurement.

22. The system of claim 21 further comprising a flash memory module, wherein said CPU stores a first ranking of said first plurality of pilot signals and a second ranking of said second plurality of pilot signals in said flash memory module.

23. The system of claim 21 wherein said first polarization is orthogonal to said second polarization.

24. The system of claim 21 wherein said first polarization and said second polarization are selected from the group consisting of vertical polarization and a horizontal polarization.

25. The system of claim 21 wherein said first polarization and said second polarization are selected from the group consisting of a right hand circular polarization and a left hand circular polarization.

26. The system of claim 21 wherein said signal quality measurement comprises a signal to interference ratio.

27. The system of claim 21 wherein said signal quality measurement comprises a signal to noise ratio.

28. The system of claim 22 wherein said first ranking of said first plurality of pilot signals is based on said signal quality measurement.

29. The system of claim 22 wherein said second ranking of said second plurality of pilot signals is based on said signal quality measurement.