Wireless Packet Preamble Layout for MU-MIMO and Punctured Channels

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Solution Overview

Problem

New wireless communication protocols require enhanced preamble designs to support signaling for new features and packet formats, particularly in full-bandwidth multi-user multiple-input multiple-output (MU-MIMO), single-user (SU) preamble puncturing, hybrid automatic repeat request (HARQ), and multi-AP coordination.

Innovation Solution

The implementation of a physical layer preamble that includes a first portion with a legacy signal field (L-SIG) and a second portion with a repeat of L-SIG and a universal signal field (U-SIG) to determine packet bandwidth and format, allowing for the reception of packets based on determined bandwidth or punctured subchannels, and processing packets according to various PPDU formats.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a legacy preamble design is used, then compatibility with existing wireless standards is maintained, but support for new features such as MU-MIMO, HARQ, and multi-AP coordination is insufficient

Engineering Contradiction:
Improvesupport for new featuresVSAvoidpreamble design complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The preamble is divided into distinct segments: a legacy portion (L-STF, L-LTF, L-SIG) for backward compatibility and a new portion (RL-SIG, U-SIG, EHT-SIG) for advanced features. This segmentation allows legacy devices to process only the legacy portion while newer devices can utilize the full preamble structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention extracts and separates the signaling functions into dedicated fields. The U-SIG field is extracted to carry universal signaling information applicable to all packet types, while EHT-SIG carries format-specific information. This extraction allows for modular and flexible feature support without complicating the overall structure.

Inventive Principle:
Principle #2Taking out (Extraction)

2Productivity

If a unified preamble design is used for all packet types, then implementation is simplified, but efficient support for special packet types such as full-bandwidth MU-MIMO and punctured channels is reduced

Engineering Contradiction:
Improvereception efficiencyVSAvoidpreamble structure
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The preamble structure adapts locally to different packet types through the EHT-SIG field, which contains format-specific signaling information. For full-bandwidth MU-MIMO packets, the signaling indicates appropriate resource allocation and user-specific parameters. For punctured channel packets, the signaling specifies which subchannels are punctured. This local adaptation enables efficient processing without requiring completely different preamble designs for each packet type.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The preamble design is dynamic and adaptable to different transmission scenarios. The U-SIG and EHT-SIG fields carry signaling information that changes based on the packet type, allowing the receiver to dynamically adjust its processing mode. This dynamic signaling enables the same preamble structure to efficiently support diverse packet formats including SU, MU-MIMO, and punctured channel transmissions.

Inventive Principle:
Principle #15Dynamics

3Measurement precision

If detailed signaling information is included for all packet formats, then accurate interpretation is enabled, but overhead increases

Engineering Contradiction:
Improvepacket format interpretation accuracyVSAvoidpreamble overhead
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The U-SIG field serves as a universal signaling field that carries information applicable to all packet types, including bandwidth indication, format identification, and basic transmission parameters. This universal field reduces the need for redundant signaling in format-specific fields, thereby reducing overall overhead while maintaining accurate interpretation capability.

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

Solution Approach 2:

The invention extracts format-specific signaling information into the EHT-SIG field, which is only processed when needed. For common packet types, the receiver can rely on U-SIG information. For special cases like full-bandwidth MU-MIMO or punctured channels, the EHT-SIG provides the additional detailed information required. This extraction strategy minimizes overhead by providing detailed information only when necessary.

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP4730729A2Physical layer preamble design for special packet types
Publication Date: 2026.04.22 QUALCOMM INC
  • EP4730729A2 patent drawingFigure 1
  • EP4730729A2 patent drawingFigure 2
  • EP4730729A2 patent drawingFigure 3A~3B

AI summary

This disclosure provides methods, devices and systems for generating packet preambles. Some implementations more specifically relate to preamble designs for special cases such as, for example, full-bandwidth multi-user multiple-input multiple-output (MU-MIMO), single-user (SU) preamble puncturing, hybrid automatic repeat request (HARQ), and multi-AP coordination. Multi-AP coordination may refer to coordinated beamforming (CoBF), joint transmission (JT), or coordinated orthogonal frequency division multiple access (C-OFDMA). Additionally, or alternatively, some implementations more specifically relate to preamble designs that accommodate signal fields of different cases.