Terminal Mobility State Reporting in Wireless Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, especially in HetNet environments, the current mobility state estimation mechanisms are inaccurate due to frequent switching between RRC_IDLE and RRC_CONNECTED states, leading to inefficient mobility control and increased signaling overhead, particularly when many cells are reselected during long idle periods.
Innovation Solution
A wireless communication system where the terminal apparatus reports mobility state information to the base station using a radio resource control message, including cell identifiers and duration of stay, with the option to use a different message type based on base station notification, thereby optimizing reporting and reducing signaling overhead.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the terminal apparatus reports detailed history information (cell identifiers and duration of stay) to the base station, then the mobility state estimation accuracy is improved, but the signaling overhead increases
Solution Approach 1:
The patent extracts only the necessary mobility state information (cell identifiers and duration of stay) from the complete history information, reporting only what is needed for mobility state estimation rather than all available data, thereby reducing signaling overhead while maintaining estimation accuracy
Solution Approach 2:
The patent implements partial reporting of history information based on the terminal's mobility characteristics and network conditions, reporting detailed information only when necessary for accurate mobility state estimation, thus balancing accuracy requirements with signaling overhead reduction
2Loss of information
If the terminal apparatus performs mobility state estimation based on cell reselection count in RRC_IDLE state, then the mobility state information is available for reporting, but the estimation accuracy deteriorates due to frequent state switching between RRC_IDLE and RRC_CONNECTED
Solution Approach 1:
The patent performs mobility state estimation in advance during the RRC_IDLE state before connection is established, preparing mobility state information that can be reported upon connection, ensuring information availability while accounting for the intermittent nature of idle state periods
Solution Approach 2:
The patent implements feedback mechanisms where the base station receives mobility state information from the terminal and uses it to adjust mobility control parameters, creating a closed-loop system that improves estimation accuracy over time by learning from actual mobility patterns
3Productivity
If the base station apparatus hands over rapidly moving terminal apparatus to small cells, then the network capacity is improved, but the handover frequency increases causing excessive signaling overhead
Solution Approach 1:
The patent implements dynamic mobility control where the base station adjusts handover parameters and small cell utilization based on the terminal's real-time mobility state, increasing network capacity for mobile terminals by optimizing handover frequency and small cell assignment according to actual mobility characteristics
Data Source
AI summary
In a wireless communication system, a terminal apparatus is capable of reporting, to a base station apparatus, information indicating a mobility state of the terminal apparatus. In a case where the terminal apparatus reports information (history information) to the base station apparatus as mobility state indicating information, the terminal apparatus notifies the base station apparatus of a radio resource control connection setup complete message containing information indicating the presence of the history information that is notified as the mobility state indicating information. The history information contains an identifier of a cell that the terminal apparatus visited and the duration of stay in the cell. The base station apparatus notifies the terminal apparatus of information as to whether to report the mobility state indicating information. In a case where the terminal apparatus reports the mobility state indicating information on the basis of the information notified by the base station apparatus, the terminal apparatus reports the history information to the base station apparatus using a radio resource control message different from the radio resource control connection setup complete message.