Method and system for explicit ap-to-ap sounding in an 802.11 network

Abstract

A method of one AP accessing a channel occupied by a neighboring AP within CCA range, by acquiring channel knowledge via performing cooperative sounding and setting a null towards the neighboring AP, under certain conditions verifications, is provided herein. The method may include: transmitting and receive signals via a plurality of radio circuitries connected to plurality of antennas; monitoring signals received by the radio circuitries and generating a list of neighboring co-channel access points that each has plurality of antennas and are further located within a clear channel assessment (CCA) range of the access point; and instructing the radio circuitries to transmit a sounding sequence to the list of neighboring access points, and receive Channel State Information (CSI).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation application of U.S. patent application Ser. No. 14 / 449,431 filed on Aug. 1, 2014, which claims benefit from U.S. Provisional Patent Application Ser. No. 61 / 955,433 filed on Mar. 19, 2014, all of which are incorporated herein by reference in their entirety.FIELD OF THE INVENTION[0002]The present invention relates generally to wireless communication, and more specifically to high efficiency Wi-Fi.BACKGROUND OF THE INVENTION[0003]Prior to setting forth the background of the invention, it may be helpful to set forth definitions of certain terms that will be used hereinafter.[0004]The term “Wi-Fi” as used herein is defined as any wireless local area network (WLAN) products that are based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards.[0005]The term “Access Point” or “AP” as used herein is defined as a device that allows wireless devices (also known as User Equipment or “UE”) ...

AI Technical Summary

Benefits of technology

This patent discusses a way for 802.11 nodes with MIMO capability to access an occupied channel using a novel procedure that involves acquiring knowledge of the channel between access points. It also describes a procedure for a neighboring access point to null its transmitted signal towards an interfering access point, based on acquiring channel knowledge via a sounding process targeted at neighboring access points. Additionally, the patent describes a mutual sounding protocol that allows a subgroup of neighboring access points to agree to establish a beamformer-beamformee nulling process to access a channel already occupied by another accessing access point. The patent also describes a beamformer's power level difference between its trained null and its omni directional antenna pattern, which is used to estimate its nulling capability.

Problems solved by technology

In many deployments APs on the same radio channel are within CCA range of each other; thus, an AP may be blocked from transmitting to its client STA due to activity of a neighboring nearby AP.

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