IMPLICIT CHANNEL TRACKING FOR SIMULTANEOUS MULTIUSER TRANSMISSION

• US 20200136699A1
• Filed: 12/26/2019
• Published: 04/30/2020
• Est. Priority Date: 12/26/2019
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Mansour, Avi, Avital, Shimon Ziv, Alpert, Yaron
• Granted Patent: US 11,271,627 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/06 using polling
• CPC Class Codes: H04W 74/0816 with collision avoidance

Abstract

Embodiments of the present disclosure provide for implicit channel tracking for simultaneous multiuser transmissions. Other embodiments may be described and claimed.

Claims

1. One or more non-transitory, computer-readable media having instructions that, when executed by one or more processors, cause an access point to:

calculate a first beamforming matrix based on feedback information received from a sounding operation;

transmit a first multiuser packet using the first beamforming matrix, the first multiuser packet to include data to be transmitted to a plurality of stations of an orthogonal frequency division multiple access (OFDMA) group;

receive, from the plurality of stations, uplink transmissions;

calculate a second beamforming matrix based on the uplink transmissions; and

transmit a second multiuser packet using the second beamforming matrix.

2. The one or more non-transitory, computer-readable media of claim 1, wherein the uplink transmissions include acknowledgment information with respect to data within the first multiuser packet.

3. The one or more non-transitory, computer-readable media of claim 1, wherein the instructions, when executed, further cause the access point to:

perform the sounding operation to acquire a channel for a transmission opportunity duration.

4. The one or more non-transitory, computer-readable media of claim 3, wherein said transmission of the second multiuser packet is within the transmission opportunity duration.

5. The one or more non-transitory, computer-readable media of claim 3, wherein the first beamforming matrix corresponds to a first state of the channel within a first portion of the transmission opportunity duration and the second beamforming matrix corresponds to a second state of the channel within a second portion of the transmission opportunity duration.

6. The one or more non-transitory, computer-readable media of claim 1, wherein the uplink transmissions include first uplink transmissions and second uplink transmissions, wherein to calculate the second beamforming matrix the access point is to:

determine reference channel values based on the first uplink transmissions;

determine updated channel values based on the second uplink transmissions; and

calculate the second beamforming matrix based on the updated channel values.

7. The one or more non-transitory, computer-readable media of claim 6, wherein the instructions when executed, further cause the access point to:

control a receive chain to receive both the first and the second uplink transmissions with a first receive state.

8. The one or more non-transitory, computer-readable media of claim 6, wherein the instructions, when executed, further cause the access point to:

correlate the reference channel values to the first beamforming matrix; and

calculate the second beamforming matrix based further on the correlation of the reference channel values to the first beamforming matrix.

9. The one or more non-transitory, computer-readable media of claim 8, wherein the instructions, when executed, further cause the access point to:

calculate the second beamforming matrix based on an inference that a change from the reference channel values to the updated channel values corresponds to a change from the first beamforming matrix to the second beamforming matrix.

10. An apparatus comprising:

memory; and

processing circuitry coupled with the memory, the processing circuitry to;

store, in the memory, first channel information based on feedback from a plurality of stations of a wireless local area network in response to one or more reference signals;

transmit a first multiuser packet to the plurality of stations based on the first channel information;

process uplink transmissions received from the plurality of stations;

store, in the memory, second channel information based on the uplink transmissions; and

transmit a second multiuser packet based on the second channel information,

wherein the first channel information corresponds to a downlink channel within a first portion of a transmission opportunity and the second channel information corresponds to the downlink channel within a second portion of the transmission opportunity.

11. The apparatus of claim 10, wherein the processing circuitry is further to perform a sounding operation to acquire the downlink channel for the transmission opportunity.

12. The apparatus of claim 10, wherein the uplink transmissions includes user uplink data or includes acknowledgment information with respect to data transmitted in the first multiuser packet.

13. The apparatus of claim 10, wherein the uplink transmissions include first uplink transmissions and second uplink transmissions and the processing circuitry is further to:

determine a first uplink (UL) channel state based on the first uplink transmissions;

determine a second UL channel state based on the second uplink transmissions;

determine an UL channel state change based on the first UL channel state and the second UL channel state;

determine a downlink (DL) channel state change based on the UL channel state change; and

determine the second channel information based on the DL channel state change.

14. The apparatus of claim 13, wherein the processing circuitry is to set components of a receive chain to be in a first receive state to receive both the first and second uplink transmissions.

15. The apparatus of claim 10, wherein the processing circuitry is further to:

generate first transmission parameters based on the first channel information; and

generate second transmission parameters based on the second channel information.

16. The apparatus of claim 15, wherein the first transmission parameters includes a first beamforming matrix or coding rate and the second transmission parameters includes a second beamforming matrix or coding rate.

18. The access point of claim 16, wherein the plurality of uplink transmissions include first uplink transmissions and second uplink transmissions and the baseband circuitry is to:

determine reference channel values based on the first uplink transmissions;

determine updated channel values based on the second uplink transmissions; and

determine the change in the uplink channel based on a comparison of the reference channel values to the updated channel values.

19. The access point of claim 16, wherein the baseband circuitry is further to control a receive chain of the radio front end module to receive the first and second uplink transmissions with a first receive state.

20. The access point of claim 16, wherein the baseband circuitry is further to:

correlate the reference channel values to the first beamforming matrix; and

calculate the second beamforming matrix based further on the correlation of the reference channel values to the first beamforming matrix.

21. The access point of claim 16, wherein the plurality of uplink transmissions include first uplink transmissions and second uplink transmissions and the baseband circuitry is to:

determine reference channel values based on the first uplink transmissions;

determine an updated reference channel values based on the second uplink transmissions; and

determine the change in the uplink channel based on a comparison of the updated channel values to the reference channel values.

22. The access point of claim 21, wherein the first uplink transmissions include the multiuser beamforming reports.

17. An access point having:

application circuitry to generate application data to be transmitted to a plurality of stations;

baseband circuitry coupled with the application circuitry to;

acquire a downlink channel for a transmission opportunity;

determine a first beamforming matrix based on a first state of the downlink channel as indicated in feedback information in multiuser beamforming reports received during acquisition of the downlink channel;

generate a first multiuser packet to be transmitted using the first beamforming matrix;

determine a change in an uplink channel based on a plurality of uplink transmissions;

determine a second state of the downlink channel based on the change in the uplink channel;

determine a second beamforming matrix based on the second state of the downlink channel; and

generate a second multiuser packet to be transmitted using the second beamforming matrix; and

a radio front end module to transmit the first and second multiuser packets within the transmission opportunity.