METHODS AND APPARATUS FOR USING MULTIPLE ANTENNAS HAVING DIFFERENT POLARIZATION

• US 20120275499A1
• Filed: 07/10/2012
• Published: 11/01/2012
• Est. Priority Date: 02/15/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Anreddy, Vikram Reddy, Wu, Xinzhou
• Granted Patent: US 8,755,833 B2
• Time in Patent Office: Days
• US Class Current: 375/219
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04B 7/0602 using antenna switching H04B7/0686 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04B 7/0805 with single receiver and antenna switching H04B7/0822 takes precedence
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

A MIMO wireless communications device supports a dual polarized mode of antenna operation and a single polarized mode of antenna operation. Antenna mode selection is performed as a function of signal to noise ration information and/or rank information corresponding to a communications channel matrix. One of a communications device'"'"'s processing chains is switched between first and second polarization orientation antennas, e.g., vertical and horizontally polarized antennas, as a function of the antenna mode selection. In various embodiments, the dual polarized mode is advantageously used for high SNR users, while in the low SNR regime, where the capacity is limited by received power, the single polarized antenna configuration, sometimes referred to as the spatial MIMO configuration, is used.

Claims

1. A communications device comprising:

a first antenna element polarized in a first direction;

a second antenna element polarized in a second direction, the second direction being different from the first direction by at least 45 degrees;

a first signal processing module coupled to the first antenna element; and

a second signal processing module coupled to the second antenna element.

2. The communications device of claim 1, wherein the first signal processing module and the second signal processing module are configured to recover data from a first received signal and a second received signal, the first received signal having a frequency that is the same as the frequency of the second received signal, and the first received signal having a first polarization different from a second polarization of the second received signal.

3. The communication device of claim 1, wherein the first signal processing module and the second signal processing module are configured to generate a first transmission signal and a second transmission signal, the first transmission signal having a frequency that is the same as the frequency of the second transmission signal, and the first transmission signal having a first polarization different from a second polarization)f the second transmission signal.

4. The communications device of claim 1, further comprising:

a third antenna element polarized in the first direction;

an antenna switching module configured to couple the second antenna element and the third antenna element to the second signal processing module, the antenna switching module selectively passing signals between the second processing module and one of the second antenna element and the third antenna element at any given time.

5. The communications device of claim 4, further comprising:

a channel quality determination module for generating channel quality indicators from received signals, the channel quality indicators including a signal to noise ratio value.

6. The communications device of claim 5, further comprising:

a channel quality information transmission control module for controlling transmission of channel quality information including the signal to noise ratio value and rank information for a channel matrix between transmitter antennas used to transmit to the communications device and receive antennas included in the communications device having a polarization which is the same as the transmitter antennas.

7. The communications device of claim 6, further comprising:

an antenna mode indicator signal detection module for detecting receipt of an antenna mode indicator signal and for recovering information indicating one of a dual polarized mode of operation and a single polarized mode of operation.

8. The communications device of claim 5, further comprising:

an antenna mode selection module for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of the generated channel quality indicators.

9. The communications device of claim 8, further comprising:

an antenna mode indicator signal generation module for generating a signal indicating the selected antenna mode of operation; and

an antenna mode indicator signal transmission control module for controlling transmission of the antenna mode indicator signal.

10. The communications device of claim 5, wherein the antenna switching module is configured to couple the second antenna element to the second signal processing module when the dual polarized mode of operation is selected;

and

wherein the antenna switching module is configured to couple the third antenna element to the second signal processing module when the single polarized mode of operation is selected.

11. The communications device of claim 10,

wherein the first direction is a vertical direction;

and

wherein the second direction is a horizontal direction.

12. The communications device of claim 2, further comprising:

an antenna mode selection module for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of received channel quality information;

wherein the first received signal and the second received signal are received through the first antenna element and the second antenna element when the dual polarized mode of operation is selected; and

wherein the first received signal and the second received signal are received through the first antenna element and the third antenna element when the single polarized mode of operation is selected.

13. The communications device of claim 2, further comprising:

an antenna mode selection module for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of received channel quality information;

wherein the first transmission signal and the second transmission signal are transmitted through the first antenna element and the second antenna element when the dual polarized mode of operation is selected; and

wherein the first transmission signal and the second transmission signal are transmitted through the first antenna element and the third antenna element when the single polarized mode of operation is selected.

14. The communications device of claim 2, wherein the communications device is a transceiver, the communications device further comprising:

a transmitter/receiver mode control module for controlling whether the communications device operates in a transmit or receive mode of operation; and

an antenna mode selection module for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of a received indicator signal, wherein the antenna mode selection module selects the dual polarized or single polarized mode of operation based on the antenna mode indicator signal.

15. The communications device of claim 14, wherein the received indicator signal is an antenna mode indicator signal.

16. The communications device of claim 14, wherein the received indicator signal is a signal from which a channel quality estimate is made;

and

wherein the antenna mode selection module selects the dual polarized mode of operation when the channel quality estimate indicates a first channel quality and selects the single polarized mode of operation when the channel quality estimate indicates a second channel quality which is lower than said first channel quality.

17. The communications device of claim 16, further comprising:

an antenna mode indicator signal generation module for generating a signal indicating the selected antenna mode of operation; and

an antenna mode indicator signal transmission control module for controlling transmission of said antenna mode indicator signal.

18. A communications device comprising:

a first antenna element means for exchanging signals in a first polarization having first polarization direction;

a second antenna element means for exchanging signals in a second polarization having a second polarization direction, the second polarization direction being different from the first polarization direction by at least 45 degrees;

a first signal processing means for processing the signals exchanged through the first antenna element means; and

a second signal processing means for processing the signals exchanged through the second antenna element means.

19. The communications device of claim 18, wherein the first signal processing means and the second signal processing means are for recovering data from a first received signal and a second received signal, the first received signal having a frequency that is the same as the frequency of the second received signal, and the first received signal having the first polarization different from the second polarization of the second received signal.

20. The communication device of claim 18, wherein the first signal processing means and the second signal processing means are for generating a first transmission signal and a second transmission signal, the first transmission signal having a frequency that is the same as the frequency of the second transmission signal, and the first transmission signal having the first polarization different from the second polarization of the second transmission signal.

21. The communications device of claim 18, further comprising:

a third antenna element means for exchanging signals in the first polarization;

an antenna switching means for coupling the second antenna element means and the third antenna element means to the second signal processing module means, the antenna switching means for selectively passing signals between the second processing means and one of the second antenna element means and the third antenna element means at any given time.

22. The communications device of claim 21, further comprising:

a channel quality determination means for generating channel quality indicators from received signals, the channel quality indicators including a signal to noise ratio value.

23. The communications device of claim 22, further comprising:

a channel quality information transmission control means for controlling transmission of channel quality information including the signal to noise ratio value and rank information for a channel matrix between transmitter antennas used to transmit to the communications device and receive antennas included in the communications device having a polarization which is the same as the transmitter antennas.

24. The communications device of claim 23, further comprising:

an antenna mode indicator signal detection means for detecting receipt of an antenna mode indicator signal and for recovering information indicating one of a dual polarized mode of operation and a single polarized mode of operation.

25. The communications device of claim 22, further comprising:

an antenna mode selection means for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of the generated channel quality indicators.

26. The communications device of claim 25, further comprising:

an antenna mode indicator signal generation means for generating a signal indicating the selected antenna mode of operation; and

an antenna mode indicator signal transmission control means for controlling transmission of the antenna mode indicator signal.

27. The communications device of claim 22, wherein the antenna switching means is configured to couple the second antenna element means to the second signal processing means when the dual polarized mode of operation is selected;

and

wherein the antenna switching means is configured to couple the third antenna element means to the second signal processing means when the single polarized mode of operation is selected.

28. The communications device of claim 27,

wherein the first polarization direction is a vertical direction;

and

wherein the second polarization direction is a horizontal direction.

29. The communications device of claim 18, further comprising:

an antenna mode selection means for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of received channel quality information;

wherein the first received signal and the second received signal are received through the first antenna element means and the second antenna element means when the dual polarized mode of operation is selected; and

wherein the first received signal and the second received signal are received through the first antenna element means and the third antenna element means when the single polarized mode of operation is selected.

30. The communications device of claim 19, further comprising:

an antenna mode selection means for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of received channel quality information;

wherein the first transmission signal and the second transmission signal are transmitted through the first antenna element means and the second antenna element means when the dual polarized mode of operation is selected; and

wherein the first transmission signal and the second transmission signal are transmitted through the first antenna element means and the third antenna element means when the single polarized mode of operation is selected.

31. The communications device of claim 19, wherein the communications device is a transceiver, the communications device further comprising:

a transmitter/receiver mode control means for controlling whether the communications device operates in a transmit or receive mode of operation; and

an antenna mode selection means for selecting between a dual polarized mode of operation and a single polarized mode of operation as a function of a received indicator signal, wherein the antenna mode selection means selects the dual polarized or single polarized mode of operation based on the antenna mode indicator signal.

32. The communications device of claim 31, wherein the received indicator signal is an antenna mode indicator signal.

33. The communications device of claim 31, wherein the received indicator signal is a signal from which a channel quality estimate is made;

and

wherein the antenna mode selection means selects the dual polarized mode of operation when the channel quality estimate indicates a first channel quality and selects the single polarized mode of operation when the channel quality estimate indicates a second channel quality which is lower than said first channel quality.

34. The communications device of claim 33, further comprising:

an antenna mode indicator signal generation means for generating a signal indicating the selected antenna mode of operation; and

an antenna mode indicator signal transmission control means for controlling transmission of said antenna mode indicator signal.