Method and system for utilizing tone grouping with Givens rotations to reduce overhead associated with explicit feedback information
Aspects of a method and system for utilizing tone grouping with Givens rotations to reduce overhead associated with explicit feedback information are presented. In one aspect of the invention, Givens matrices may be utilized to reduce a quantity of information communicated in explicit feedback information via an uplink RF channel. The explicit feedback information may include specifications for a feedback beamforming matrix that may be utilized when transmitting signals via a corresponding downlink RF channel. The feedback beamforming matrix may represent a rotated version of an un-rotated matrix. The Givens matrices may be utilized to apply one or more Givens rotations to un-rotated matrix. The rotated matrix may reduce the quantity of information communicated in the explicit feedback information. The quantity of information communicated in the explicit feedback information may be further reduced by utilizing tone grouping.
1. A method for processing signals, comprising:
in a device that is operable for MIMO communication:
determining one or more Givens rotation angles and corresponding phase rotation angles for a beamforming matrix that corresponds to an RF channel;
selecting a tone group size;
selecting, based on the selected tone group size, frequency carriers from a plurality of frequency carriers that correspond to the RF channel; and
encoding the determined one or more Givens rotations angles and corresponding phase rotation angles that correspond to the selected frequency carriers to produce encoded information for transmission.
2. The method of claim 1 , wherein the selected tone group size is 2.
3. The method of claim 1 , wherein the selected tone group size is 4.
4. The method of claim 1 , wherein the selected tone group size is selected from a plurality of tone group sizes supported by the device.
5. The method of claim 1 , wherein the RF channel is a 20 MHz channel.
6. The method of claim 1 , wherein the RF channel is a 40 MHz channel.
7. The method of claim 1 , wherein the RF channel is a downlink RF channel, the method comprising:
transmitting the encoded information via an uplink RF channel.
8. The method of claim 1 , comprising generating the beamforming matrix based on signals received by the device via the RF channel.
9. The method of claim 1 , comprising binary encoding the determined one or more Givens rotations angles and corresponding phase rotation angles that correspond to the selected frequency carriers.
10. A system for processing signals, comprising:
one or more processors and/or circuits for use in a device that is operable for MIMO communication, the one or more processors and/or circuits being operable to:
determine one or more Givens rotation angles and corresponding phase rotation angles for a beamforming matrix that corresponds to an RF channel;
select a tone group size;
select, based on the selected tone group size, frequency carriers from a plurality of frequency carriers that correspond to the RF channel; and
encode the determined one or more Givens rotations angles and corresponding phase rotation angles that correspond to the selected frequency carriers to produce encoded information for transmission.
11. The system of claim 10 , wherein the selected tone group size is 2.
12. The system of claim 10 , wherein the selected tone group size is 4.
13. The system of claim 10 , wherein the selected tone group size is selected from a plurality of tone group sizes supported by the device.
14. The system of 10 , wherein the RF channel is a 20 MHz channel.
15. The system of claim 10 , wherein the RF channel is a 40 MHz channel.
16. The system of claim 10 , wherein:
the RF channel is a downlink RF channel; and
the one or more processors and/or circuits are operable to transmit the encoded information via an uplink RF channel.
17. The system of claim 10 , wherein the one or more processors and/or circuits are operable to generate the beamforming matrix based on signals received by the device via the RF channel.
18. The system of claim 10 , wherein the one or more processors and/or circuits are operable to generate the beamforming matrix utilizing a phase shifting matrix.
19. The system of claim 10 , wherein the one or more processors and/or circuits are operable to binary encode the determined one or more Givens rotations angles and corresponding phase rotation angles that correspond to the selected frequency carriers.
20. A system for processing signals, comprising:
one or more circuits for used in a MIMO communication device, the one or more circuits being operable to:
determine one or more Givens rotation angles and corresponding phase rotation angles for a beamforming matrix that corresponds to an RF channel;
select a tone group size from a plurality of tone group sizes that comprise a tone group size having a value of 2 and a tone group size having a value of 4;
select, based on the selected tone group size, frequency carriers from a plurality of frequency carriers that correspond to the RF channel; and
encode the determined one or more Givens rotations angles and corresponding phase rotation angles that correspond to the selected frequency carriers to produce encoded information for transmission.