Base Station Handover Control Using Reduced Data Messages
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing handover techniques in mobile communications fail due to large data size of control signals, leading to low delivery probability and prolonged 'out of service range' states when wireless communication quality deteriorates, as re-fragmenting PDU data into smaller sizes increases the number of fragments and fails to reduce control signal data size effectively.
Innovation Solution
A communications processing device and method for a base station that acquires measurement reports from mobile terminals, determines wireless quality, and sends a handover instruction or RRC connection release message with a smaller data volume when quality is below a threshold, ensuring higher delivery probability and reducing call disconnection to reconnection time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a handover instruction message is sent to the mobile communications terminal, then handover can be initiated, but the large data size reduces delivery probability when wireless communication quality deteriorates
Solution Approach 1:
The patent extracts only the essential information needed for handover (carrier frequency of target base station) from the full handover instruction message, creating a simplified control signal that can be delivered reliably even when communication quality deteriorates. This extraction approach removes non-essential data while preserving the core handover functionality.
Solution Approach 2:
The patent changes the parameter of message data size by selecting a simplified message type with smaller payload. The base station determines that when delivery probability is below the threshold, it should use a control signal with reduced data size (containing only carrier frequency information) rather than the complete handover instruction message.
2Reliability
If PDU data is re-fragmented into smaller sizes, then data transmission may be improved, but the number of fragments increases and delivery probability further lowers
Solution Approach 1:
Instead of fragmenting the large handover instruction message into multiple PDU parts (which increases complexity and reduces delivery probability), the patent inverts the approach by sending a single, inherently small control signal containing only the essential carrier frequency information. This eliminates the fragmentation problem entirely.
3Loss of time
If only system information block is used for cell search upon handover failure, then cell selection can be performed, but no appropriate cell can be immediately selected and the out of service range state continues
Solution Approach 1:
The patent provides preliminary action by including the carrier frequency of the target base station in the simplified control signal before the mobile terminal needs to perform cell search. This advance provision of frequency information enables the terminal to immediately search for and connect to the appropriate cell without relying solely on system information blocks, significantly reducing the time to recover from handover failure.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A communications processing device that reduces the time after call disconnection until call reconnection, by using a message having a higher delivery probability than a handover instruction, when wireless quality could result in handover instruction failure. The communications processing device comprises: a measurement report acquisition unit that obtains a measurement report relating to a communications environment from a mobile communications terminal located within the cell; a wireless quality determination unit that determines whether or not the quality of wireless communications with the mobile communications terminal, included in the measurement report, is lower than a threshold value; and a message transmission unit that, if the wireless quality is less than the threshold value, sends to the mobile communications terminal a message that has less data volume than a handover instruction message and includes the carrier frequency for the base station to be handed over.