Autonomous Uplink Transmission in Unlicensed NR Spectrum
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current technologies face challenges in efficiently managing time and frequency resources for autonomous uplink transmissions in unlicensed new radio spectra, leading to potential collisions and increased latency.
Innovation Solution
The proposed solution involves flexible time resource allocation, autonomous frequency resource selection, and enhanced configured grants to support multiple repetitions, frequency and time hopping, and dynamic bandwidth adaptation, allowing UEs to autonomously select and switch resources for efficient transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If flexible time resource allocation is implemented for autonomous uplink transmission, then system adaptability and transmission efficiency are improved, but resource management complexity increases
Solution Approach 1:
The patent segments time resources into discrete allocation units and configures multiple candidate time resource patterns. The gNB segments the resource management task by providing pre-defined patterns that the UE can autonomously select from, rather than managing every time slot centrally. This reduces real-time management complexity while maintaining flexibility through the segmented pattern library.
Solution Approach 2:
The patent implements preliminary action by pre-configuring multiple time resource allocation patterns through RRC signaling before autonomous transmission begins. The gNB prepares a library of valid time resource patterns in advance, allowing the UE to autonomously select appropriate patterns without real-time gNB intervention. This preliminary configuration reduces operational complexity during actual autonomous transmission.
2Loss of time
If autonomous frequency resource selection is implemented, then transmission autonomy and latency are reduced, but collision probability increases
Solution Approach 1:
The patent segments the frequency spectrum into multiple Bandwidth Parts (BWPs) and further divides each BWP into multiple candidate frequency resources. This segmentation allows UEs to select from a diversified set of frequency options rather than competing for a single resource pool, reducing collision probability while maintaining autonomous selection capability and low latency.
Solution Approach 2:
The patent enables parameter changes by allowing UEs to autonomously change frequency resource parameters (selecting different BWPs and frequency offsets) based on channel conditions and transmission requirements. The gNB configures multiple candidate parameters in advance, and UEs can switch between them dynamically, reducing latency while the diversified parameter set helps avoid collisions.
3Reliability
If multiple configured grants with repetitions are supported, then transmission reliability is improved, but resource overhead increases
Solution Approach 1:
The patent merges multiple configured grants into a unified framework where a single grant configuration can specify multiple repetitions across different time resources. Instead of treating each repetition as a separate grant requiring individual configuration, the patent combines them into one grant structure, reducing configuration overhead while maintaining the reliability benefits of multiple transmissions.
Solution Approach 2:
The patent implements universality by designing a configured grant structure that can serve multiple functions: it can specify a single transmission or multiple repetitions, support different time resource patterns, and accommodate various BWP configurations. This multi-functional grant structure reduces overall resource overhead by eliminating the need for separate configurations for each transmission instance.
4Adaptability or versatility
If dynamic BWP switching is implemented for autonomous resources, then resource allocation flexibility is improved, but switching overhead and complexity increase
Solution Approach 1:
The patent applies preliminary action by pre-configuring multiple BWPs and their associated parameters through RRC signaling before autonomous transmission. The gNB prepares a library of BWP configurations in advance, allowing the UE to switch between them autonomously without real-time signaling overhead. This preliminary preparation enables flexible BWP switching while minimizing the complexity and overhead of dynamic reconfiguration.
Data Source
AI summary
Hybrid automatic repeat request (HARQ) processes may be transmitted via configured grants as well as scheduled grants. The configured grants may include time and frequency resources, and transmissions may occur across contiguous transmissions. HARQ process information, such as HARQ IDs and redundancy versions, may be communicated via a control channel, and the control channel may be multiplexed with the transmission resources of the configured grants. Retransmission timers may be used for HARQ processes conveyed via configured grants, and the transmitting apparatus may signal to a receiver when to send an acknowledgement. An acknowledgement may take the form of bitmaps for code block groups of a HARQ. A configured grant may be selected from among multiple configured grants based upon low latency, for example. A group of configured grants may be activated or deactivated via a single command.