Sidelink Cyclic Prefix Extension for Shared Spectrum

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current wireless communication systems, particularly in 4G and 5G networks, face challenges in efficiently coordinating sidelink transmissions between user equipment (UEs) due to limitations in channel access procedures and cyclic prefix extensions, which affect data transmission quality and interference management.

Innovation Solution

A method for wireless devices to determine the appropriate channel access procedure and cyclic prefix extension based on physical layer priorities during sidelink transmissions, optimizing channel occupancy time by selecting the most suitable procedure and extension length to minimize interference and maximize data transfer efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If channel access procedures and cyclic prefix extensions are not optimized, then sidelink transmission coordination is simple, but data transmission quality and interference management deteriorate

Engineering Contradiction:
Improvedata transmission qualityVSAvoidchannel access procedure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements dynamic selection of channel access procedure types (Type 1, Type 2a, Type 2b, Type 2c) and cyclic prefix extension lengths based on real-time transmission conditions, physical layer priorities, and gap durations. This dynamic adaptation allows the system to optimize reliability for each transmission while managing complexity through conditional logic rather than fixed complex procedures

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes key parameters including channel access procedure type, cyclic prefix extension length, and timing adjustments based on physical layer priority values and gap durations. By dynamically adjusting these parameters, the system improves transmission quality without requiring fundamentally complex coordination mechanisms

Inventive Principle:
Principle #35Parameter changes

2Productivity

If channel occupancy time is extended to improve data transfer efficiency, then more data can be transmitted, but interference with other transmissions increases

Engineering Contradiction:
Improvedata transfer efficiencyVSAvoidinterference with other transmissions
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent implements periodic channel sensing and channel access procedures within the channel occupancy time. The transmitting device performs Listen-Before-Talk (LBT) checks at regular intervals and releases the channel after a maximum occupancy duration, creating periodic transmission patterns that balance data transfer efficiency with interference management

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The patent incorporates feedback mechanisms where receiving devices send acknowledgments and channel status information back to transmitting devices. This feedback enables dynamic adjustment of transmission parameters and channel release decisions, allowing the system to maintain high productivity while responding to interference conditions

Inventive Principle:
Principle #23Feedback

3Measurement precision

If cyclic prefix extension length is increased to accommodate larger gaps, then timing synchronization improves, but transmission overhead increases

Engineering Contradiction:
Improvetiming synchronizationVSAvoidtransmission overhead
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent dynamically selects cyclic prefix extension lengths (CP extension type 1, type 2, type 3, or no extension) based on the actual gap duration between transmissions and physical layer priorities. This dynamic selection achieves timing synchronization only when necessary, minimizing transmission overhead while maintaining synchronization precision for large gaps

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies different cyclic prefix extension configurations to different transmission segments based on local requirements. Instead of using a uniform extension length for all transmissions, the system applies extensions selectively to specific transmissions with larger gaps, optimizing the balance between synchronization and overhead

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP4406336B1Sidelink communications in shared spectrum
Publication Date: 2024.12.18 OFINNO LLC
  • EP4406336B1 patent drawingFigure 1A~1B
  • EP4406336B1 patent drawingFigure 2A~2B
  • EP4406336B1 patent drawingFigure 3

AI summary

The disclosure relates to methods, systems, apparatuses, and computer readable mediums for performing sidelink communications. In an example, a wireless device may transmit a cyclic prefix extension (CPE) of a sidelink transmission and the sidelink transmission. A length of the CPE may be determined, from among a plurality of CPEs, based on a priority of the sidelink transmission.