DMG CTS Timeout Calculation for Variable Training Fields

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In directional multi-gigabit (DMG) networks, existing methods for calculating the TXOP continuation timeout based on the length of DMG CTS frames are inaccurate due to variable training fields, leading to incorrect setting of Network Allocation Vectors (NAV) and potential collisions.

Innovation Solution

A wireless communication device calculates the CTS_Time parameter for DMG CTS frames by considering the maximum size of the training length field and other time parameters, such as control mode preamble, header, and beamforming training fields, to accurately determine the TXOP continuation timeout.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the TXOP continuation timeout is calculated based on the actual length of DMG CTS frames, then the timeout accuracy is improved, but the device complexity increases due to the need to account for variable training fields

Engineering Contradiction:
Improvetimeout accuracyVSAvoidcalculation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by pre-calculating and storing the maximum possible training field length in a lookup table during system initialization. This allows the device to quickly retrieve the maximum training field value without performing complex real-time calculations, thus improving timeout accuracy while minimizing computational complexity during operation.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements dynamics by making the timeout calculation adaptive to the actual training field length. The system dynamically adjusts the timeout value based on the retrieved maximum training field length from the lookup table, allowing the timeout to be optimized for each specific transmission scenario while maintaining efficient computation.

Inventive Principle:
Principle #15Dynamics

2Reliability

If the training field length is included in the timeout calculation, then collision reduction is improved, but the latency increases due to extended timeout duration

Engineering Contradiction:
Improvecollision reductionVSAvoidlatency
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent applies parameter changes by adjusting the timeout calculation to include only the necessary components (preamble, header, and maximum training field) rather than using fixed conservative values. This dynamic parameter adjustment ensures the timeout is long enough to prevent collisions while minimizing unnecessary waiting time, thus balancing reliability and latency.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses partial action by including only the essential time components needed for accurate timeout calculation. Rather than adding excessive margin time, the system calculates the precise timeout based on the actual frame structure requirements, achieving sufficient collision protection without unnecessary latency extension.

Inventive Principle:
Principle #16Partial or excessive action

3Measurement precision

If the maximum training field length is used for timeout calculation, then NAV setting accuracy is improved, but the potential latency increases for shorter training fields

Engineering Contradiction:
ImproveNAV setting accuracyVSAvoidpotential latency
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies beforehand cushioning by using the maximum training field length to calculate the timeout, which provides a safety margin for all possible training field configurations. This ensures NAV setting accuracy and collision prevention for all cases, while the actual latency impact is minimized because the maximum value is used only when necessary, and the system is optimized to handle typical cases efficiently.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Data Source

PatentEP3446530B1Transmit opportunity continuation timeout for directional multi-gigabit networks
Publication Date: 2025.09.10 INTEL CORP
  • EP3446530B1 patent drawingFigure 1a
  • EP3446530B1 patent drawingFigure 1b
  • EP3446530B1 patent drawingFigure 2

AI summary

A wireless communication device, system and method. The device includes a memory, and processing circuitry coupled to the memory. The processing circuitry includes logic to: determine a training field length associated with a directional multigigabit (DMG) CTS frame of another wireless communication device; determine a Clear-To-Send time (CTS_Time) parameter based at least in part on the training field length; determine a transmit opportunity (TXOP) continuation timeout for the device based on the CTS_Time parameter; and set a network allocation vector (NAV) for the device based on the TXOP continuation timeout.