Sidelink COT Gap Slot Handling via S-SSB Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In wireless communication systems, maintaining channel occupancy time (COT) without explicit signaling is challenging, especially when sidelink-synchronization signal block (S-SSB) gap slots interrupt the COT, leading to potential loss of communication.

Innovation Solution

A non-SLSS UE initiates a COT and identifies gap slots allocated for S-SSB transmissions. If a capable SLSS UE is detected, the non-SLSS UE assumes the SLSS UE will transmit an S-SSB during the gap slot, thereby maintaining the COT without explicit signaling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If explicit signaling is used to maintain COT with SLSS UE, then COT continuity is ensured, but signaling overhead increases

Engineering Contradiction:

ImproveCOT continuityVSAvoidsignaling overhead

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

The non-SLSS UE autonomously determines whether to perform LBT after a gap slot by detecting the presence of SLSS UEs and assessing their S-SSB transmission capability, eliminating the need for explicit network signaling to maintain COT continuity

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The non-SLSS UE uses feedback from SLSS UE detections and S-SSB capability assessments to dynamically adjust its LBT behavior, ensuring COT maintenance only when SLSS UEs are present and capable of filling gap slots

Inventive Principle:

Principle #23Feedback

2Reliability

If LBT is performed after every gap slot, then channel access is ensured, but transmission delay increases

Engineering Contradiction:

Improvechannel accessVSAvoidtransmission delay

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The non-SLSS UE performs LBT operation selectively (partially) after gap slots only when SLSS UEs are not detected or are incapable of S-SSB transmission, avoiding unnecessary LBT operations when the channel is already occupied by capable SLSS UEs

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The LBT operation decision is dynamically adjusted based on real-time detection of SLSS UE presence and S-SSB transmission capability, transitioning between performing LBT and skipping LBT based on channel conditions

Inventive Principle:

Principle #15Dynamics

3Productivity

If COT is maintained without LBT after gap slot, then transmission efficiency is improved, but channel collision risk increases

Engineering Contradiction:

Improvetransmission efficiencyVSAvoidchannel collision

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The non-SLSS UE uses feedback from SLSS UE detection and S-SSB capability assessment to determine whether to skip LBT, maintaining high transmission efficiency only when channel occupancy is confirmed through SLSS UE presence

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

SLSS UEs act as intermediaries that validate channel occupancy during gap slots through their S-SSB transmissions, allowing non-SLSS UEs to safely skip LBT when SLSS UEs are present and capable

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS20250056602A1Channel occupancy time transmissions with a sidelink-synchronization signal block gap slot

Publication Date: 2025.02.13 QUALCOMM INC

AI summary

Methods, systems, and devices for wireless communication are described. A non-sidelink synchronization signal (SLSS)-transmitting user equipment (UE) may initiate a channel occupancy time (COT) including multiple contiguous slots and a gap slot. The non-SLSS UE may detect an SLSS UE (capable of transmitting sidelink synchronization signal blocks (S-SSBs)) and assume that the gap slot will be filled with an S-SSB. The non-SLSS may transmit a sidelink message during the COT after the gap slot, based on the assumption. Alternatively, based on the SLSS UE indicating that it is capable of transmitting the S-SSB, the non-SLSS UE may schedule transmission of the S-SSB such that the gap slot is filled. If the SLSS UE is incapable of transmitting the S-SSB, the non-SLSS UE may determine a method for transmitting the sidelink message during the already-initiated COT or during another COT.