Virtual LBT for NR-U Channel Access Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face inefficiencies in channel access and resource management in unlicensed shared spectrum, leading to increased signaling overhead and latency due to the need for each device to contend for resources, especially in scenarios with multiple network operators accessing shared resources.
Innovation Solution
Implementing virtual full listen before talk (LBT) procedures and generating measurement reports with detailed statistics to improve channel access efficiency, allowing devices to better assess channel occupancy and adjust their access strategies based on real-time data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If each device performs independent LBT procedures to access shared spectrum resources, then channel access fairness is improved, but signaling overhead and access latency increase
Solution Approach 1:
The base station performs LBT procedures in advance on behalf of multiple UEs and pre-allocates granted transmission resources (time, frequency, power) based on these preliminary channel access decisions. This eliminates the need for each UE to perform independent LBT, reducing access latency while maintaining fairness through the base station's centralized channel assessment.
Solution Approach 2:
The base station acts as an intermediary between multiple UEs and the shared spectrum channel. It centralizes the LBT function, performing channel listening and occupancy determination once, then distributes the results to multiple UEs in the form of granted resources. This mediator approach replaces multiple independent LBT procedures with a single centralized operation.
2Measurement precision
If detailed LBT measurement reports are generated and transmitted, then channel occupancy measurement precision is improved, but signaling overhead increases
Solution Approach 1:
A single set of detailed LBT measurement reports generated by the base station serves multiple UEs simultaneously. The base station performs one comprehensive channel assessment and generates one measurement report that contains channel occupancy information useful for all served UEs, rather than each UE generating and transmitting its own separate measurement reports.
Solution Approach 2:
The base station creates a single authoritative copy of the LBT measurement results and distributes this information to multiple UEs through downlink control signaling. Instead of each UE creating its own measurement copy, the base station's single measurement serves as the source of truth for all UEs, reducing redundant signaling.
Data Source
AI summary
Enhanced measurements for new radio-unlicensed (NR-U) operations are disclosed. Compatible user equipments (UEs) may be configured to perform virtual full listen before talk (LBT) procedures for measurement purposes. The UEs may then compile LBT statistics derived from the virtual LBT procedures and include such statistics in an enhanced measurement report the their serving base stations. The LBT statistics provide a more direct and detailed reflection of the usage of a shared communication channel. Such UEs may further be configured to gather additional LBT statistics from transmission-based LBT procedures in addition to the virtual LBT procedures. The additional direct and detailed usage of a shared channel may then be provided in the enhanced measurement reports in accordance with described aspects.