Semi-Static Uplink Channel Access via COT Segmentation

Solution Overview

Problem

In 5G wireless systems, especially in unlicensed bands like 60 GHz, there is a need for efficient channel access mechanisms to manage configured uplink transmissions, as existing methods face challenges with increased resource consumption and reduced flexibility in dynamic time domain scheduling, particularly when using beam-based operations.

Innovation Solution

The proposed solution involves a method where a gNB indicates time portions for Cat-1 ('No LBT') and Cat-2 ('single LBT sensing') channel access within channel occupancy time (COT), allowing user equipment (UE) to determine the appropriate channel access mechanism based on these indications, thereby optimizing channel access for configured uplink transmissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If LBT schemes are used for channel access in unlicensed bands, then channel access reliability is improved, but transmission latency increases and resource consumption increases

Engineering Contradiction:

Improvechannel access reliabilityVSAvoidtransmission latency

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent segments the channel occupancy time into multiple time portions, each with different channel access requirements. The gNB indicates to the UE which time portions allow Cat-1 channel access (no LBT) versus Cat-2 channel access (single LBT sensing). This segmentation allows the system to use LBT only when necessary while using simpler access methods otherwise, reducing overall latency while maintaining reliability.

Inventive Principle:

Principle #1Segmentation

2Reliability

If LBT schemes are used for channel access in unlicensed bands, then channel access reliability is improved, but resource consumption increases

Engineering Contradiction:

Improvechannel access reliabilityVSAvoidresource consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent segments the channel occupancy time into multiple time portions, each with different channel access requirements. The gNB indicates to the UE which time portions allow Cat-1 channel access (no LBT) versus Cat-2 channel access (single LBT sensing). This segmentation allows the system to use LBT only when necessary while using simpler access methods otherwise, reducing overall resource consumption while maintaining reliability.

Inventive Principle:

Principle #1Segmentation

3Adaptability or versatility

If dynamic time domain scheduling is used with beam-based operations, then adaptability is improved, but device complexity increases

Engineering Contradiction:

Improvedynamic scheduling flexibilityVSAvoidscheduling complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by having the gNB pre-indicate to the UE the channel access requirements for different time portions within the COT before the UE needs to transmit. The indication is provided in advance, allowing the UE to determine the appropriate channel access mechanism (Cat-1 or Cat-2) without complex real-time decisions, thereby reducing device complexity while maintaining dynamic scheduling flexibility.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11844108B2Channel access for semi-static uplink resources

Publication Date: 2023.12.12 NOKIA TECHNOLOGIES OY

AI summary

Systems, methods, apparatuses, and computer program products for channel access for semi-static uplink (UL) resources are provided. One method may include receiving, at a user equipment, an indication of at least one of time portions of channel occupancy time (COT) where the user equipment can use a first type of channel access for configured uplink (CUL) transmission or time portions where a second type of channel access is required prior to the configured uplink (CUL) transmission. The method may then include, based on the received indication, determining a channel access mechanism to use when transmitting on a configured uplink (CUL) resource.