Broadcast TWT Scheduling for Low-Delay Wi-Fi Services

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing Target Wake Time (TWT) mechanism in the 802.11ax standard involves significant signaling overheads and imbalances service fairness due to the establishment of TWT service periods at the granularity of individual terminals, leading to increased signaling packets and prioritization of services within these periods.

Innovation Solution

A method and apparatus are introduced to reduce signaling overheads and balance service fairness by configuring transmission times for low-delay services, utilizing an access point to schedule and manage TWT service periods across multiple terminals, thereby optimizing channel access and reducing collisions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of time

If TWT service periods are established at the granularity of individual terminals, then channel access delay and service delay are reduced, but signaling overheads increase significantly

Engineering Contradiction:
Improvechannel access delayVSAvoidsignaling overhead
Core Design Contradiction:
Loss of timeVSLoss of information

Solution Approach 1:

The patent merges multiple individual TWT service periods into a single broadcast TWT service period that serves multiple terminals simultaneously. Instead of establishing separate TWT SPs for each terminal, the access point broadcasts a unified TWT SP that multiple terminals can share, thereby reducing the quantity of signaling packets from O(N) to O(1) where N is the number of terminals.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The broadcast TWT service period serves multiple terminals with different service requirements simultaneously. The access point identifies terminals that can share the same TWT SP based on their service characteristics, allowing a single TWT SP to function for multiple terminals rather than requiring individual dedicated TWT SPs for each terminal.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Loss of time

If TWT service periods are established for terminals, then low-delay services are prioritized, but service fairness is affected

Engineering Contradiction:
Improveservice delayVSAvoidservice fairness
Core Design Contradiction:
Loss of timeVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by allowing different terminals to have different behaviors within the same broadcast TWT SP. Terminals with low-delay services can transmit during the TWT SP with prioritization, while terminals without such services or with different delay requirements can continue normal channel contention. This creates differentiated service quality tailored to local terminal needs while maintaining overall fairness.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP4255037B1Service transmission method, apparatus and system
Publication Date: 2025.09.24 HUAWEI TECH CO LTD
  • EP4255037B1 patent drawingFigure 1~2
  • EP4255037B1 patent drawingFigure 3~4a
  • EP4255037B1 patent drawingFigure 4b~5

AI summary

This application relates to the field of wireless fidelity Wi-Fi technologies, and in particular, to a service transmission method, an apparatus, and a system. In this method, an access point generates and sends a broadcast frame, where the broadcast frame includes information about a first transmission time and an identifier of a first low-delay service, the first transmission time is used to transmit the first low-delay service, and the first low-delay service is a low-delay service of at least one first terminal. After a terminal receives the broadcast frame, when services of the terminal include the first low-delay service, the terminal transmits the first low-delay service within the first transmission time. When services of the terminal do not include the first low-delay service, the terminal stops channel contention within the first transmission time. Based on this solution, signaling overheads of configuring, by the access point, a transmission time of a low-delay service for the terminal can be reduced, and service fairness can further be balanced.