Uplink Timing Advance Management in Dual Connectivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In dual connectivity scenarios, the timing advance differences between MeNB and SeNB cell sets can lead to overlapping uplink subframes, exceeding the maximum transmit power of UE, causing potential network connection breaks and performance damage when the timing advance difference exceeds a threshold.
Innovation Solution
A communication method where the terminal adjusts the timing advance offset and calculates differences between cell sets, stopping uplink transmission in affected cell sets when the threshold is reached to prevent connection loss and network damage, by requesting configuration changes and signaling to base stations to manage cell sets and adjust timing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the terminal simultaneously sends uplink subframes in both cell sets, then the uplink transmission efficiency is improved, but the transmit power exceeds the maximum limit due to overlapping areas caused by different TAs
Solution Approach 1:
The patent extracts the overlapping area between uplink subframes and removes it from simultaneous transmission. When overlap is detected, the terminal stops sending uplink data in one of the cell sets during the overlapping period, ensuring transmit power remains within limits while allowing transmission in non-overlapping areas.
Solution Approach 2:
The patent applies partial action by allowing uplink transmission in only one cell set during overlapping areas, rather than completely stopping all uplink transmissions. This maintains some transmission activity while avoiding power excess, achieving a balance between efficiency and power constraints.
2Measurement precision
If the TA of the first cell set is adjusted to improve uplink timing alignment, then the timing accuracy is improved, but the TA difference between cell sets exceeds the maximum timing difference, causing connection breaks
Solution Approach 1:
The patent implements a feedback mechanism where the terminal continuously monitors the TA difference between cell sets. When the difference approaches or exceeds the maximum timing difference threshold, the terminal sends uplink sending stopping instructions to the base station, which then adjusts the TA to maintain connection stability while preserving timing accuracy.
Solution Approach 2:
The patent applies preliminary anti-action by proactively stopping uplink transmission before the TA difference actually causes connection breakdown. When the TA difference reaches a critical threshold, the terminal preemptively sends stopping instructions to prevent the harmful effect of connection breaks.
3Power
If the terminal stops uplink transmission in one cell set to avoid power excess, then the transmit power limit is maintained, but the uplink transmission efficiency decreases
Solution Approach 1:
The patent applies partial action by stopping uplink transmission only in the overlapping area of one cell set while maintaining transmission in non-overlapping areas. This selective approach minimizes the impact on overall transmission efficiency while ensuring power limits are not exceeded during overlapping periods.
Solution Approach 2:
The patent implements periodic monitoring of uplink subframe overlaps and dynamically adjusts transmission behavior. The terminal continuously checks for overlapping areas and applies stopping instructions only when necessary, allowing efficient transmission during non-overlapping periods while maintaining power control during overlapping periods.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
Embodiments of the present invention provide a communication method, a communications apparatus, and a base station, and relate to the communications field. The method includes: obtaining, by a terminal, a timing advance TA offset of a first cell set, where the first cell set includes at least one cell, and the at least one cell is a cell that is of a first base station and whose TA needs to be adjusted; determining, by the terminal, a TA difference between the first cell set and each cell set of a second base station according to the TA offset of the first cell set after a TA of the first cell set is adjusted; and if there is a second cell set that is in the cell sets of the second base station and of which a TA difference from the first cell set reaches a preset threshold, stopping, by the terminal, uplink transmission in the first cell set or the second cell set according to a type of the first cell set and a type of the second cell set. In the present invention, a case in which the terminal breaks a connection to a network node and further huge damage is caused to network performance can be avoided.