Method and apparatus for transmission polarization selection for a cellular base station

• US 20040203538A1
• Filed: 08/21/2002
• Published: 10/14/2004
• Est. Priority Date: 08/21/2002
• Status: Abandoned Application

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Laurila, Juha K., Hugl, Klaus, Leppanen, Kari J.
• Application Number:
  US10/224,324
• Publication Number:
  US 20040203538A1
• Time in Patent Office: Days
• US Class Current: 455/101
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

A method and apparatus for transmission polarization selection that includes receiving a signal from a device where the signal is received at two or three polarizations each polarization being orthogonal to each other. The polarization receiving the signal having the best performance characteristics is determined. Transmissions to the device are routed through appropriate transceivers and antennas such that they are transmitted using a polarization the same as that receiving the signal having the best performance characteristics. Performance characteristics measured may include highest power level, highest signal to noise ratio (SNR), highest carrier to interference ratio (CIR), highest signal to noise plus interference ratio (SNIR), lowest bit error ratio (BER), or lowest block error ratio (BLER).

Claims

1. A method for transmission polarization selection comprising:

receiving a signal from a device, the signal being received at two or three polarizations, each polarization being orthogonal to each other;

determining the polarization receiving the signal having the best performance characteristics; and

transmitting to the device using a polarization the same as that receiving the signal having the best performance characteristics.

2. The method according to claim 1, further comprising determining the polarization receiving the signal having the highest power level and transmitting to the device using a polarization the same as that receiving the signal having the highest power level.

3. The method according to claim 1, further comprising determining the polarization receiving the signal having the highest signal-to-noise ratio (SNR) and transmitting to the device using a polarization the same as that receiving the signal having the highest SNR.

4. The method according to claim 1, further comprising determining the polarization receiving the signal having the highest carrier-to-interference ratio (CIR) and transmitting to the device using a polarization the same as that receiving the signal having the highest CIR.

5. The method according to claim 1, further comprising determining the polarization receiving the signal having the highest signal-to-noise plus interference ratio (SNIR) and transmitting to the device using a polarization the same as that receiving the signal having the highest SNIR.

6. The method according to claim 1, further comprising determining the polarization receiving the signal having the lowest bit error ratio (BER) and transmitting to the device using a polarization the same as that receiving the signal having the lowest BER.

7. The method according to claim 1, further comprising determining the polarization receiving the signal having the lowest block error ratio (BLER) and transmitting to the device using a polarization the same as that receiving the signal having the lowest BLER.

8. The method according to claim 1, further comprising determining the polarization receiving the signal having the best performance characteristics using appropriate time averaging.

9. The method according to claim 1, further comprising determining the polarization receiving the signal having the best performance characteristics based on a statistical aspect of the performance characteristic.

10. The method according to claim 1, further comprising receiving a signal from a device, the signal being received at a single antenna having antenna ports having orthogonal polarizations to each other.

11. The method according to claim 1, further comprising receiving a signal from a device, the signal being received at two or three antennas each having orthogonal polarizations to each other.

12. The method according to claim 1, further comprising receiving a signal from a device, the signal being received at two or more antennas per orthogonal polarization.

13. The method according to claim 12, further comprising transmitting to the device using transmission diversity techniques.

14. The method according to claim 13, further comprising transmitting to the device using at least one of phase hopping, delay diversity, and space-time codes.

15. The method according to claim 12, further comprising transmitting to the device using beamforming.

16. A method for transmission polarization selection at a base station comprising:

receiving a signal from each of a plurality of mobile devices, each signal being received at a base station, each signal being received at polarizations orthogonal to each other;

determining for each signal received from each mobile device the polarization receiving the signal having the best performance characteristics; and

transmitting to each mobile device using a polarization the same as that receiving the signal having the best performance characteristics for the received signal from that mobile device.

17. The method according to claim 16, further comprising determining for each signal received from each mobile device the polarization receiving the signal having the highest power level and transmitting to each mobile device using a polarization the same as that receiving the signal having the highest power level for the received signal from that mobile device.

18. The method according to claim 16, further comprising determining for each signal received from each mobile device the polarization receiving the signal having the highest signal-to-noise ratio (SNR) and transmitting to each mobile device using a polarization the same as that receiving the signal having the highest SNR for the received signal from that mobile device.

19. The method according to claim 16, further comprising determining for each signal received from each mobile device the polarization receiving the signal having the highest carrier-to-interference ratio (CIR) and transmitting to each mobile device using a polarization the same as that receiving the signal having the highest CIR for the received signal from that mobile device.

20. The method according to claim 16, further comprising determining for each signal received from each mobile device the polarization receiving the signal having the highest signal-to-noise plus interference ratio (SNIR) and transmitting to each mobile device using a polarization the same as that receiving the signal having the highest SNIR for the received signal from that mobile device.

21. The method according to claim 16, further comprising determining for each signal received from each mobile device the polarization receiving the signal having the lowest bit error ratio (BER) and transmitting to each mobile device using a polarization the same as that receiving the signal having the lowest BER for the received signal from that mobile device.

22. The method according to claim 16, further comprising determining for each signal received from each mobile device the polarization receiving the signal having the lowest block error ratio (BLER) and transmitting to each mobile device using a polarization the same as that receiving the signal having the lowest BLER for the received signal from that mobile device.

23. The method according to claim 16, further comprising:

formulating a ratio, for the signal received from each mobile device, comprising the performance characteristics of the signal received at one polarization as a numerator and the performance characteristics of the signal received at another polarization as the denominator;

calculating values of the ratios and sorting these values into a list from highest value to lowest value;

transmitting to the mobile devices with ratio values in the upper half of the list using a polarization the same as that which received the signals with performance characteristics in the numerator of the ratios; and

transmitting to the mobile devices with ratio values in the lower half of the list using a polarization the same as that which received the signals with performance characteristics in the denominator of the ratios.

24. The method according to claim 16, further comprising:

formulating a ratio, for the signal received from each mobile device, comprising the performance characteristics of the signal received at one polarization as a numerator and the performance characteristics of the signal received at another polarization as the denominator;

calculating values of the ratios and sorting these values into a list from lowest value to highest value;

transmitting to the mobile devices with ratio values in the upper half of the list using a polarization the same as that which received the signals with performance characteristics in the numerator of the ratios; and

transmitting to the mobile devices with ratio values in the lower half of the list using a polarization the same as that which received the signals with performance characteristics in the denominator of the ratios.

25. The method according to claim 16, further comprising:

formulating a ratio, for the signal received from each mobile device, comprising the performance characteristics of the signal received at one polarization as a numerator and the performance characteristics of the signal received at another polarization as the denominator;

calculating values of the ratios and grouping the values larger than one into a first group and the remainder of the values into a second group;

transmitting to the mobile devices with ratio values in the first group using a polarization the same as that which received the signals with performance characteristics in the numerator of the ratios; and

transmitting to the mobile devices with ratio values in the second group using a polarization the same as that which received the signals with performance characteristics in the denominator of the ratios.

26. The method according to claim 16, further comprising:

formulating a ratio, for the signal received from each mobile device, comprising the performance characteristics of the signal received at one polarization as a numerator and the performance characteristics of the signal received at another polarization as the denominator;

calculating values of the ratios and grouping the values less than one into a first group and the remainder of the values into a second group;

transmitting to the mobile devices with ratio values in the first group using a polarization the same as that which received the signals with performance characteristics in the numerator of the ratios; and

transmitting to the mobile devices with ratio values in the second group using a polarization the same as that which received the signals with performance characteristics in the denominator of the ratios.

27. The method according to claim 16, further comprising transmitting to each mobile device using two or more antennas having the same polarization.

28. The method according to claim 27, further comprising transmitting to each mobile device using transmission diversity techniques.

29. The method according to claim 28, further comprising transmitting to each mobile device using at least one of phase hopping, delay diversity, and space-time codes.

30. The method according to claim 27, further comprising transmitting to each mobile device using beamforming.

31. A base station for transmission polarization selection comprising:

at least two antenna receive ports, the at least two antenna receive ports having at least two orthogonal polarizations, the at least two antenna receive ports receiving a signal from a mobile device;

at least two antenna transmit ports, the at least two antenna transmit ports having at least two orthogonal polarizations; and

a processor subsystem, the processor subsystem measuring performance characteristics of the signal received at each at least two antenna receive ports, the processor subsystem determining which antenna receive port received the signal with the best performance characteristics and controlling transmissions from the base station to the mobile device to be sent on the at least two antenna transmit ports having the same polarization as the antenna receive port receiving the signal with the best performance characteristics.

32. The base station according to claim 31, further comprising at least two transceivers operatively connected to the at least two antenna receive ports and the at least two antenna transmit ports.

33. The base station according to claim 32, the processor subsystem further comprising a frequency controller, the frequency controller capable of adjusting a radio frequency of each at least two transceivers.

34. The base station according to claim 32, the processor subsystem further comprising at least one base band processor, one base band processor being associated with each at least two transceivers and performing base band processing for signals received and transmitted between the base station and the mobile device.

35. The base station according to claim 32, the processor subsystem further comprising a selection unit, the selection unit routing signals for transmission to the mobile device to the appropriate at least one transceiver.

36. The base station according to claim 35, the processor subsystem further comprising a control unit, the control unit receiving information regarding which antenna receive port(s) having a single polarization received the signal with the best performance characteristics and controlling the selection unit to route the signals for transmission to the mobile device to the appropriate at least one transceiver.

37. The base station according to claim 32, further comprising at least two combiner units, each combiner unit routing signals received from a subset of the at least two transceivers to one antenna transmit port with a given polarization.

38. The base station according to claim 31, the processor subsystem further comprising a performance measuring unit for measuring the power level of the signal received at the at least one antenna receive port of each polarization.

39. The base station according to claim 31, the processor subsystem further comprising a performance measuring unit for measuring the signal-to-noise ratio (SNR) of the signal received at the at least one antenna receive port of each polarization.

40. The base station according to claim 31, the processor subsystem further comprising a performance measuring unit for measuring the carrier-to-interference ratio (CIR) of the signal received at the at least one antenna receive port of each polarization.

41. The base station according to claim 31, the processor subsystem further comprising a performance measuring unit for measuring the signal-to-noise plus interference ratio (SNIR) of the signal received at the at least one antenna receive port of each polarization.

42. The base station according to claim 31, the processor subsystem further comprising a performance measuring unit for measuring the bit error ratio (BER) of the signal received at the at least one antenna receive port of each polarization.

43. The base station according to claim 31, the processor subsystem further comprising a performance measuring unit for measuring the block error ratio (BLER) of the signal received at the at least one antenna receive port of each polarization.

44. The base station according to claim 31, wherein the base station comprises a GSM base station.

45. The base station according to claim 31, wherein the base station comprises a GSM EDGE base station.

46. The base station according to claim 31, wherein the base station comprises a Wireless Local Area Network (WLAN) base station.

47. The base station according to claim 31, wherein the base station comprises a TDMA base station.

48. An apparatus comprising a storage medium with instructions stored therein, the instructions when executed causing a computing device to perform:

receiving a signal from a device, the signal being received at two or three polarizations orthogonal to each other;

determining the polarization receiving the signal having the best performance characteristics; and

transmitting to the device using a polarization the same as that receiving the signal having the best performance characteristics.