Coordinated Spatial Nulling Trigger Frame for WLAN Interference

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In dense WLAN environments, interference between overlapping networks using the same frequency channel leads to increased latency and reduced data rates, as existing technologies like clear channel assessment and spatial reuse methods fail to effectively manage simultaneous transmissions.

Innovation Solution

Implement coordinated spatial nulling (C-SN) and coordinated spatial reuse (C-SR) techniques, where access points align transmission start-times and adjust transmit power, precoding, and beamforming to minimize interference, using feedback mechanisms to optimize channel assignments and modulation schemes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If clear channel assessment and spatial reuse methods are used to manage simultaneous transmissions, then device complexity is reduced, but interference between overlapping networks increases leading to higher latency and reduced data rates

Engineering Contradiction:

Improvecomplexity of transmission managementVSAvoiddata rate

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The system performs preliminary channel assessment and coordination between access points before simultaneous transmissions occur. The first AP communicates with the second AP to coordinate spatial nulling parameters in advance, allowing both APs to transmit simultaneously with pre-calculated interference mitigation strategies, thus achieving high data rates without complex real-time management

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The first access point acts as an intermediary that coordinates between itself and the second access point. By establishing a coordination mechanism where the first AP shares channel state information and receives spatial nulling parameters from the second AP, the system enables simultaneous transmissions with controlled interference, improving overall network productivity

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If coordinated spatial nulling is implemented to reduce interference, then throughput is enhanced, but device complexity increases due to alignment requirements

Engineering Contradiction:

ImprovethroughputVSAvoidcomplexity of coordination mechanism

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The system implements a feedback mechanism where the second AP provides spatial nulling parameters to the first AP based on channel state information. This feedback loop enables the first AP to adjust its transmission to minimize interference, achieving high throughput while keeping coordination complexity manageable through automated parameter exchange

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system dynamically changes transmission parameters including spatial nulling vectors, power levels, and timing alignment based on channel conditions. By automatically adjusting these parameters through the coordination mechanism, the system achieves high throughput without requiring complex manual configuration or intervention

Inventive Principle:

Principle #35Parameter changes

3Productivity

If access points transmit simultaneously to increase productivity, then data rates improve, but interference between networks increases

Engineering Contradiction:

Improvedata rateVSAvoidinterference

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The system converts the harmful interference effect into a beneficial coordination mechanism. By having the second AP measure the channel to the first AP and calculate spatial nulling parameters, the interference problem becomes the basis for optimizing simultaneous transmissions, allowing both APs to achieve high data rates with controlled interference levels

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The system performs preliminary channel assessment and spatial nulling parameter calculation before simultaneous transmissions begin. The second AP evaluates channel conditions and pre-computes the spatial nulling vector that the first AP should apply, ensuring that when both APs transmit simultaneously, interference is minimized from the outset, maintaining high productivity

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS20250212008A1Alignment in coordinated spatial nulling (c-sn)

Publication Date: 2025.06.26 MAXLINEAR INC

AI summary

Technology is disclosed for an access point (AP) including a processing device and a transceiver. The processing device may compute, at the AP, a coordinated spatial nulling (C-SN) trigger frame. The C-SN trigger frame may align a start-time for C-SN transmission from a second AP. The transceiver may transmit, from the AP to the second AP, the C-SN trigger frame.