Handover Alignment via Random Access Timing Offset
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current handover procedures in communication networks result in significant interruption times for mobile devices as they transition between base stations, with existing methods failing to minimize the duration of service disruption effectively.
Innovation Solution
The method involves determining a time offset associated with random access opportunities in the target cell to align the start of the handover with the next available random access opportunity, thereby reducing the waiting period and minimizing service disruption by delaying the handover execution until just before the random access opportunity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the mobile device disconnects from the serving base station before establishing connection with the target base station, then the handover can be executed cleanly, but the service interruption time increases
Solution Approach 1:
The patent applies preliminary action by having the mobile device perform the random access procedure to the target base station before actually disconnecting from the serving base station. The device sends a random access preamble, receives timing advance information, and establishes uplink synchronization in advance, so that when the handover is executed, the connection switch is seamless and service interruption is minimized or eliminated.
2Ease of operation
If the random access procedure is executed at the next available random access opportunity, then the procedure is simple and standardized, but the waiting period before random access can be initiated increases
Solution Approach 1:
The patent enables preliminary execution of the random access procedure by providing the mobile device with timing advance information and random access configuration parameters before the actual handover. This allows the device to perform the random access preamble transmission and receive synchronization information in advance, rather than waiting for the next scheduled random access opportunity after disconnection.
3Speed
If the handover command is sent immediately when signal strength threshold is met, then the handover response time is fast, but the mobile device may disconnect before being ready for random access
Solution Approach 1:
The patent resolves this contradiction by sending the handover command with embedded timing advance information and random access configuration parameters in advance. This allows the mobile device to prepare the random access procedure beforehand, ensuring it is ready to execute immediately upon receiving the handover command, thus achieving both fast response time and high execution success rate.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method and apparatus for reducing handover interruptions when a mobile device executes handover including a random access procedure is described herein. When handover is desirable, a time offset associated with a random access opportunity is determined. The time offset relates the timing of the next random access opportunity to the frame timing of a target access point. Based on the time offset, a network element, e.g., the mobile device, a serving access point, or a mobility management entity, determines a handover start time. Handover is executed at the determined start time to generally align the beginning of the handover execution with the beginning of the next random access opportunity, and therefore, to reduce handover interruption.