Uplink Transmission Node Selection in Dual Connectivity Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In the context of New Radio (NR) communication systems, there is a challenge in achieving low latency and high reliability due to the need for determining the optimal uplink transmission node based on buffer capacity, which can lead to increased latency and synchronization signal overlap issues when sharing frequencies between LTE and NR.
Innovation Solution
A communication system that employs an uplink transmission node determination process to select the node providing the lowest latency for uplink data transmission, allowing for flexible configuration of nodes for improved latency and reliability, including the use of split bearers and transmission without grant mechanisms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the uplink transmission node is determined based on buffer capacity in NR systems, then resource allocation flexibility is improved, but transmission latency increases
Solution Approach 1:
The patent implements dynamic uplink transmission node selection where the UE can switch between transmitting to the gNB directly or via the eNB based on buffer capacity thresholds. This dynamic adaptation allows the system to optimize between latency (direct transmission) and resource flexibility (relay transmission) depending on current buffer conditions, resolving the contradiction between these two parameters.
2Productivity
If frequencies are shared between LTE and NR, then spectrum efficiency is improved, but synchronization signal overlap occurs
Solution Approach 1:
The patent segments the frequency resource usage by assigning different synchronization signal transmission patterns to LTE and NR systems. The gNB transmits NR synchronization signals in specific subframes while the eNB transmits LTE synchronization signals in other subframes, effectively dividing the time-frequency resources to prevent overlap while maintaining spectrum sharing benefits.
3Reliability
If the UE transmits uplink data to the gNB with buffer capacity check, then transmission reliability is improved, but latency increases due to additional processing
Solution Approach 1:
The patent implements preliminary buffer capacity checking and transmission node selection before actual data transmission. The UE continuously monitors its buffer capacity and pre-determines the optimal transmission node (eNB or gNB) based on configured thresholds, so that when data arrives, the transmission path is already decided, minimizing additional processing latency while maintaining reliability.
Data Source
AI summary
A communication system includes a user apparatus; and base stations respectively configured to wirelessly communicate with the user apparatus. The base stations include a master base station and a secondary base station that configure dual connectivity for the user apparatus. The secondary base station is configured with a grant configuration related to transmission without grant in uplink to the secondary base station.