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US-20260128772-A1 - WLAN SPATIAL NULLING

US20260128772A1US 20260128772 A1US20260128772 A1US 20260128772A1US-20260128772-A1

Abstract

An access point (AP) may include a transceiver and a processing device. The transceiver may be operable to communicate with at least a second AP and at least a first station (STA). The processing device may be operable to transmit a null data packet announcement and a joint null data packet from the AP and the second AP. The processing device may also be operable to request a sounding feedback from the first STA. The processing device may further be operable to obtain a channel estimation feedback from the second AP. The processing device may also be operable to perform a precoder calculation using the sounding feedback and the channel estimation feedback. The processing device may further be operable to provide the precoder calculation to the second AP.

Inventors

  • Rainer Strobel
  • Avi Avraham Mansour
  • Ziv Avital
  • Sigurd Schelstraete

Assignees

  • MAXLINEAR, INC.

Dates

Publication Date
20260507
Application Date
20251106

Claims (20)

  1. 1 . An access point (AP), comprising: a transceiver operable to communicate with at least a second AP and at least a first station (STA); a processing device operable to: transmit a null data packet announcement (NDPA) and a joint null data packet (NDP) from the AP and the second AP; request a sounding feedback from the first STA; obtain a channel estimation feedback from the second AP; perform a precoder calculation using the sounding feedback and the channel estimation feedback; and provide the precoder calculation to the second AP.
  2. 2 . The AP of claim 1 , wherein the NDPA is jointly transmitted at the same time by the AP and the second AP.
  3. 3 . The AP of claim 1 , wherein the NDPA is transmitted by the AP at a first dedicated time slot and a second NDPA is transmitted by the second AP at a second dedicated time slot.
  4. 4 . The AP of claim 1 , wherein the second AP requests a second sounding feedback from a second STA associated with the second AP, and the second AP determines the channel estimation feedback using the second sounding feedback.
  5. 5 . The AP of claim 1 , wherein the channel estimation feedback comprises a feedback exchange packet obtained from the second AP.
  6. 6 . The AP of claim 5 , wherein the feedback exchange packet comprises a different tone grouping and quantization bits relative to the sounding feedback.
  7. 7 . The AP of claim 5 , wherein the feedback exchange packet is transmitted between the AP and the second AP via a non-wireless local area network link.
  8. 8 . The AP of claim 5 , wherein the feedback exchange packet is transmitted between the AP and the second AP at a different time interval than transmission of the sounding feedback.
  9. 9 . An access point (AP), comprising: a transceiver operable to communicate with at least a second AP and at least a first station (STA); a processing device operable to: transmit a first NDPA and a first NDP from the AP; obtain a sounding feedback from the first STA in response to the first NDPA and the first NDP; transmit a nulling report poll (RP) to a second STA; obtain a first nulling feedback from the second STA in response to the nulling RP; cause a transmission of a second NDPA and a second NDP from the second AP, wherein the second AP obtains a second channel estimation feedback from the second STA and a second nulling feedback from the first STA; and determine an equalizer for the first STA based on the sounding feedback, the first nulling feedback, the second channel estimation feedback, and the second nulling feedback.
  10. 10 . The AP of claim 9 , wherein the first NDPA and the second NDPA are jointly transmitted at the same time by the AP and the second AP.
  11. 11 . The AP of claim 9 , wherein the first STA listens to packets from the AP and not the second AP, and the second STA listens to packets from the second AP and not the AP.
  12. 12 . The AP of claim 9 , wherein the first nulling feedback is transmitted with a different tone grouping and quantization bits than transmission of the sounding feedback.
  13. 13 . The AP of claim 9 , wherein the first nulling feedback is transmitted at a different time interval than transmission of the sounding feedback.
  14. 14 . The AP of claim 9 , wherein the nulling RP comprises transmit precoding operable to improve mutual nulling between the AP and the second AP.
  15. 15 . A method, comprising: transmitting a null data packet announcement (NDPA) and a joint null data packet (NDP) from an access point (AP) to a second AP; requesting a sounding feedback from a first station (STA) associated with the AP; obtaining a channel estimation feedback from the second AP; performing a precoder calculation using the sounding feedback and the channel estimation feedback; and providing the precoder calculation to the second AP.
  16. 16 . The method of claim 15 , wherein the NDPA is transmitted by the AP at a first dedicated time slot and a second NDPA is transmitted by the second AP at a second dedicated time slot.
  17. 17 . The method of claim 15 , wherein the second AP requests a second sounding feedback from a second STA associated with the second AP, and the second AP determines the channel estimation feedback using the second sounding feedback.
  18. 18 . The method of claim 15 , wherein: the channel estimation feedback comprises a feedback exchange packet obtained from the second AP; and the feedback exchange packet comprises a different tone grouping and quantization bits relative to the sounding feedback.
  19. 19 . The method of claim 18 , wherein the feedback exchange packet is transmitted between the AP and the second AP via a non-wireless local area network link.
  20. 20 . The method of claim 18 , wherein the feedback exchange packet is transmitted between the AP and the second AP at a different time interval than transmission of the sounding feedback.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This U.S. patent application claims priority to U.S. Provisional Patent Application No. 63/717,276, titled “WLAN SPATIAL NULLING,” and filed on Nov. 6, 2024, the disclosure of which is hereby incorporated by reference in its entirety. TECHNICAL FIELD This disclosure generally relates to wireless communication, and more specifically, to spatial nulling in a wireless local area network. BACKGROUND Unless otherwise indicated herein, the materials described herein are not prior art to the claims in the present application and are not admitted to be prior art by inclusion in this section. Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards include protocols for implementing wireless local area network (WLAN) communications, including Wi-Fi®. Multiple access point coordination is a key feature of ultra-high reliability (UHR) WLAN. Spatial re-use with spatial nulling may increase spectral efficiency as spatial reuse may allow simultaneous transmission in the same frequency band from multiple access points (APs). Multiple-input and multiple-output (MIMO) precoding techniques may be used to suppress interference between neighboring WLAN networks (overlapping basic service sets (OBSS)), which is called spatial nulling. The subject matter claimed in the present disclosure is not limited to implementations that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one example technology area where some implementations described in the present disclosure may be practiced. SUMMARY In an example embodiment, an access point (AP) may include a transceiver and a processing device. The transceiver may be operable to communicate with at least a second AP and at least a first station (STA). The processing device may be operable to transmit a null data packet announcement (NDPA) and a joint null data packet (NDP) from the AP and the second AP. The processing device may also be operable to request a sounding feedback from the first STA. The processing device may further be operable to obtain a channel estimation feedback from the second AP. The processing device may also be operable to perform a precoder calculation using the sounding feedback and the channel estimation feedback. The processing device may further be operable to provide the precoder calculation to the second AP. In another embodiment, an access point (AP) may include a transceiver and a processing device. The transceiver may be operable to communicate with at least a second AP and at least a first STA. The processing device may be operable to transmit a null data packet announcement and a joint null data packet from the AP. The processing device may also be operable to obtain a sounding feedback from the first STA in response to the first NDPA and the first NDP. The processing device may further be operable to transmit a nulling report poll (RP) to a second STA. The processing device may also be operable to obtain a first nulling feedback from the second STA in response to the nulling RP. The processing device may further be operable to cause a transmission of a second NDPA and a second NDP from the second AP. The second AP may obtain a second channel estimation feedback from the second STA and a second nulling feedback from the first STA. The processing device may also be operable to determine an equalizer for the first STA based on the sounding feedback, the first nulling feedback, the second channel estimation feedback, and the second nulling feedback. In another embodiment, a method may include transmitting an NDPA and an NDP from an AP to a second AP. The method may also include requesting a sounding feedback from a first STA associated with the AP. The method may further include obtaining a channel estimation feedback from the second AP. The method may also include performing a precoder calculation using the sounding feedback and the channel estimation feedback. The method may further include providing the precoder calculation to the second AP. The objects and advantages of the embodiments will be realized and achieved at least by the elements, features, and combinations particularly pointed out in the claims. Both the foregoing general description and the following detailed description are given as examples and are explanatory and not restrictive of the invention, as claimed. DESCRIPTION OF DRAWINGS Example implementations will be described and explained with additional specificity and detail using the accompanying drawings in which: FIG. 1 illustrates an example system for wireless local area network (WLAN) spatial nulling using joint sounding; FIG. 2 illustrates an example system for WLAN spatial nulling using joint sounding with a single null data packet (NDP) transmission; FIGS. 3A and 3B illustrate an example system for WLAN spatial nulling using joint sounding with a double NDP transmission; FIG. 4