Multi-User WLAN Acknowledgment via OFDMA

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current wireless local area network (WLAN) standards, such as IEEE 802.11 standards, face challenges in efficiently managing multi-user multiple input-multiple output (MU-MIMO) and orthogonal frequency division multiple access (OFDMA) transmissions, leading to increased channel overhead and limited data throughput in acknowledging downlink (DL) and uplink (UL) communications.

Innovation Solution

Implementing a method where a wireless communication device generates and transmits MU-MIMO signals and receives OFDMA signals to acknowledge data units, optimizing the transmission process by determining the appropriate frequency portions for acknowledgment, thereby reducing channel overhead and enhancing data throughput.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If traditional acknowledgment methods are used in MU-MIMO transmissions, then reliability of data reception is maintained, but channel overhead increases and data throughput is limited

Engineering Contradiction:
Improvedata throughputVSAvoidchannel overhead
Core Design Contradiction:
ProductivityVSLoss of energy

Solution Approach 1:

The patent combines multiple acknowledgment signals from multiple user devices into a single OFDMA signal transmission. Instead of each device sending separate acknowledgment signals, the system merges them into one consolidated transmission using orthogonal frequency division multiple access, thereby reducing channel overhead while maintaining reliability

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent transitions from traditional single-user acknowledgment methods to multi-user acknowledgment by introducing frequency dimension multiplexing. Different user devices transmit acknowledgments on different frequency subcarriers within the same OFDMA signal, enabling simultaneous acknowledgments without interference and reducing overall channel overhead

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If separate acknowledgment transmissions are used for each user device, then acknowledgment reliability is ensured, but transmission time and channel efficiency decrease

Engineering Contradiction:
Improvetransmission efficiencyVSAvoidacknowledgment transmission time
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent enables continuous and simultaneous acknowledgment transmissions from multiple user devices through the OFDMA mechanism. All devices can transmit their acknowledgments at the same time on different frequency resources, eliminating sequential waiting and maximizing channel utilization without losing time

Inventive Principle:
Principle #20Continuity of useful action

3Productivity

If MU-MIMO signals are transmitted to multiple devices, then data throughput increases, but complexity of managing acknowledgments increases

Engineering Contradiction:
Improvedata throughputVSAvoidacknowledgment management complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent creates a universal acknowledgment mechanism using OFDMA that can handle acknowledgments from any number of user devices simultaneously. The same OFDMA signal structure and frequency resource allocation principles apply regardless of how many devices are involved, providing a scalable and simple management approach for multi-user acknowledgments

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

Data Source

PatentEP3219041B1Acknowledgment for multiple user communication in a WLAN
Publication Date: 2020.06.17 NXP USA INC
  • EP3219041B1 patent drawingFigure 1
  • EP3219041B1 patent drawingFigure 2
  • EP3219041B1 patent drawingFigure 3

AI summary

A first communication device generates a multi-user (MU) physical layer (PHY) data unit having independent data for multiple second communication devices. The first communication device also generates respective control frames to prompt second communication devices to transmit an orthogonal frequency division multiple access (OFDMA) PHY data unit to acknowledge that the second communication devices received the MU PHY data unit. The MU PHY data unit and the respective control frames are transmitted to the multiple second communication devices. The first communication device receives the OFDMA PHY data unit from at least some of the second communication devices. The first communication device processes the OFDMA PHY data unit to determine whether the multiple second communication devices received the MU PHY data unit.