System and method capable of implicit feedback for the devices with an unequal number of transmitter and receiver chains in a wireless local area network

• US 8,279,972 B2
• Filed: 11/05/2010
• Issued: 10/02/2012
• Est. Priority Date: 12/07/2004
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Li, Qinghua, Lin, Xintian Eddie
• Primary Examiner(s): Singh, Hirdepal
• Application Number:
  US12/940,700
• Publication Number:
  US 20110053545A1
• Time in Patent Office: 697 Days
• Field of Search: 375/130, 375/135, 375/147, 375/260, 375/262, 375/267, 375/271, 375/295, 375/297, 375/299, 375/316, 375/322, 375/347, 375/349, 375/300, 375/343, 375/346
• US Class Current: 375/297
• CPC Class Codes: H04B 7/0421 utilizing implicit feedback, e.g. steered pilot signals
• CPC Class Codes: H04L 1/0675 characterised by the signaling

Abstract

An embodiment of the present invention provides a wireless station (STA) capable of implicit feedback in a wireless local area network, comprising at least one power amplifier, a plurality of antennas capable of being connected with said at least one power amplifier, and a switch capable of switching the connection between said plurality of antennas and said at least one power amplifier thereby enabling said wireless station to sound a complete channel matrix for an access point (AP) in communication with said wireless station (STA).

Claims

1. An apparatus, comprising:

a plurality of power amplifiers;

a plurality of antennas, the plurality of antennas including at least one antenna to receive wireless data signals and to not transmit wireless data signals, wherein the at least one antenna is capable of being connected with a first power amplifier of the plurality of power amplifiers; and

a switch to switch a connection with the first power amplifier, said switching comprising switching between the at least one antenna and at least one other of the plurality of antennas, said switching to occur when the apparatus is sounding a complete channel matrix for a remote device, the apparatus operative to rank each of the plurality of antennas based on power received in one or more packets received from an access point and transmit a short preamble to the access point using a strongest antenna and a weakest antenna from among the plurality of antennas.

2. The apparatus of claim 1, wherein all of said plurality of power amplifiers are switchably connected to said plurality of antennas.

3. The apparatus of claim 1, wherein said plurality of antennas are three antennas and said plurality of power amplifiers are two power amplifiers;

and

wherein both of said power amplifiers are switchably connected to all of three said antennas.

4. The apparatus of claim 1, wherein the complete channel matrix is a 3×

4 channel matrix.

5. The apparatus of claim 1, wherein said switching occurs during one or more long preambles.

6. The apparatus of claim 1, wherein the complete channel matrix corresponds to a multiple input multiple output (MIMO) wireless communications channel.

7. The apparatus of claim 1, wherein the complete channel matrix corresponds to an uplink channel with the access point.

8. A method, comprising:

providing a plurality of antennas in a wireless station, the plurality of antennas including at least one antenna to receive wireless data signals and to not transmit wireless data signals, wherein the at least one antenna is capable of being connected with a first power amplifier of a plurality of power amplifiers;

ranking each of the plurality of antennas based on power received in one or more packets received from an access point;

switching a connection with a first of the plurality of power amplifiers, said switching comprising switching between the at least one antenna and at least one other antenna of said plurality of antennas, said switching to occur when the wireless station is sounding a complete channel matrix for a remote device; and

transmitting a short preamble to the access point using a strongest antenna and a weakest antenna from among the plurality of antennas.

9. The method of claim 8, further comprising connecting switchably all of said plurality of power amplifiers to all of said plurality of antennas.

10. The method of claim 8, wherein said plurality of antennas are three antennas and said plurality of power amplifiers are two power amplifiers;

and

wherein the method further comprises connecting switchably both of said two power amplifiers to all of said three antennas.

11. The method of claim 8, wherein the complete channel matrix is a 3×

4 channel matrix.

12. The method of claim 8, wherein said switching occurs during one or more long preambles.

13. The method of claim 8, wherein the complete channel matrix corresponds to a multiple input multiple output (MIMO) wireless communications channel.

14. An article comprising a non-transitory storage medium having stored thereon instructions, that, when executed by a computing platform causes a wireless station comprising a plurality of antennas to:

rank each of the plurality of antennas based on power received in one or more packets received from an access point;

switch a connection with a first of a plurality of power amplifiers, said switching comprising switching between a first antenna of said plurality of antennas and a second antenna of said plurality of antennas, said switching to occur when the wireless station is sounding a complete channel matrix for a remote device; and

transmit a short preamble to the access point using a strongest antenna and a weakest antenna from among the plurality of antennas;

wherein the first antenna is to receive wireless data signals and is to not transmit wireless data signals, and the at least one antenna is capable of being connected with the first power amplifier of the plurality of power amplifiers.

15. The article of claim 14, wherein the instructions, when executed by a computer platform, further cause connecting switchably all of said pluratliy of power amplifiers to all of said plurality of antennas.

16. The article of claim 14, wherein said plurality of antennas are three antennas and said plurality of power amplifiers are two power amplifiers;

and

wherein the instructions, when executed by a computer platform, further cause connecting switchably both of said two power amplifiers to all of said three antennas.

17. The article of claim 14, wherein the complete channel matrix is a 3×

4 channel matrix.

18. The article of claim 14, wherein said switching occurs during one or more long preambles.

19. The article of claim 14, wherein the complete channel matrix corresponds to a multiple input multiple output (MIMO) wireless communications channel.

20. The article of claim 14, wherein the complete channel matrix corresponds to an uplink channel with the access point.