Conditional Handover Terminal Device Adaptation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In mobile communications systems, especially in high-frequency scenarios like LTE and 5G, conventional handover mechanisms face failures due to rapid channel quality attenuation, terminal device movement, and obstructions, leading to decreased handover success rates, as the handover message may not be successfully sent.
Innovation Solution
A conditional handover method where the terminal device determines a target cell based on initial CHO configuration information and can reassess or change the target cell upon receiving subsequent CHO configuration information, allowing it to continue or alter the handover process accordingly to ensure reliability and system performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the network device sends a handover message to control the terminal device to be handed over from the source cell to a target cell, then the handover process can be initiated, but the handover message may fail to be sent successfully due to rapid attenuation of channel quality, rapid movement of the terminal device, or obstruction of an object, leading to handover failure
Solution Approach 1:
The network device sends conditional handover (CHO) configuration information to the terminal device in advance when the quality of the source link is good. This configuration information includes handover trigger conditions and information about one or more candidate cells. The terminal device stores this information and can immediately execute handover to a suitable candidate cell when the trigger condition is met, without needing to wait for a new handover message from the network device, thus overcoming the problem of handover message failure due to rapid channel quality attenuation.
2Reliability
If the terminal device performs random access procedure with the target cell after determining the target cell based on CHO configuration information, then the handover can be completed, but the terminal device may receive new CHO configuration information during the access process, creating uncertainty about whether to continue to the original target cell
Solution Approach 1:
The terminal device dynamically adjusts its handover decision based on newly received CHO configuration information. When new CHO configuration information is received during the random access process, the terminal device compares the new information with the stored configuration information. If the new information indicates a different target cell or different handover conditions, the terminal device updates its decision accordingly. This dynamic adjustment mechanism ensures that the terminal device makes the most appropriate handover decision based on the latest network instructions while maintaining clear decision logic.
Data Source
AI summary
This disclosure provides a handover method, a communications apparatus, and a terminal device. The handover method includes determining a first target cell based on first conditional handover (CHO) configuration information, where the first target cell is a cell to which the terminal device is to be handed over, and in a process of attempting to access the first target cell, when receiving second CHO configuration information, determining, based on the second CHO configuration information, whether to continue to be handed over to the first target cell.