Conditional Handover Triggering with Layer 1 Measurements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing 3GPP conditional handover (CHO) in 5G NR communication systems experiences excessive handover delays due to layer 3 (L3) measurement delays, affecting throughput and mobility performance.
Innovation Solution
Implementing layer 1 (L1) measurement-based trigger events for conditional handover (CHO) by configuring UE with trigger events based on L1 measurement results, including criteria such as L1-RSRP or L1-SINR, to reduce measurement delays and optimize handover timing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If layer 3 (L3) measurement is used for conditional handover, then handover reliability is improved, but handover delay increases excessively
Solution Approach 1:
The patent segments the measurement process into two distinct layers: Layer 1 (L1) measurement for rapid signal quality assessment and Layer 3 (L3) measurement for final handover decision. This segmentation allows the system to use fast L1 measurements to quickly identify candidate cells and trigger conditions, while relying on more reliable L3 measurements for the actual handover execution, thereby reducing overall handover delay while maintaining reliability
Solution Approach 2:
The patent implements preliminary L1 measurements continuously before handover is needed. These preliminary measurements pre-assess signal qualities of serving and candidate cells, so when handover conditions arise, the UE and network already have current measurement data ready, eliminating the need to wait for L3 measurement completion and thus reducing handover delay
2Speed
If layer 3 (L3) measurement delay is reduced, then handover speed is improved, but measurement precision may be compromised
Solution Approach 1:
The patent introduces L1 measurement results as an intermediary between fast speed requirements and precision requirements. L1 measurements provide rapid initial assessment that triggers handover conditions, while L3 measurements provide the precise final verification. This intermediary approach allows the system to achieve fast handover speed through L1 while maintaining measurement precision through L3
Solution Approach 2:
The patent performs preliminary L1 measurements continuously in advance, so when handover is needed, measurement data is already available immediately rather than waiting for slower L3 measurements to complete, thus achieving fast handover speed without compromising precision
3Loss of time
If L1 measurement is implemented for CHO trigger, then handover delay is reduced, but system complexity increases
Solution Approach 1:
The patent segments measurement responsibilities between different layers: L1 measurement handles the time-critical trigger detection function, while L3 measurement handles the less time-sensitive verification function. This segmentation reduces handover delay by assigning fast measurement tasks to L1, while managing system complexity by clearly defining the boundaries and roles of each layer
Solution Approach 2:
The patent enables the UE to autonomously perform L1 measurements and independently evaluate trigger conditions based on configured criteria without requiring constant network intervention. This self-service capability reduces handover delay by enabling autonomous fast measurement and trigger detection, while managing complexity through standardized self-evaluation algorithms
Data Source
Figure 1~4
Figure 5~7
Figure 8~10
AI summary
The present disclosure provides a communication method and apparatus, and a readable storage medium. The method comprises: sending configuration information to a user equipment, wherein the configuration information comprises a trigger event corresponding to a Layer 1 measurement result, and the trigger event is used for triggering conditional handover (CHO). In the method of the present disclosure, a network device sends configuration information to a user equipment so as to issue to the user equipment a trigger event corresponding to a Layer 1 measurement result, such that after receiving the configuration information, the user equipment can perform Layer 1 measurement according to the configuration information, thereby effectively reducing the measurement delay, and preventing the throughput and mobility performance of a communication system from being affected by excessively long handover delay.