MAC-hs Reordering Timer for Radio Communication Sequence Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In radio communications, particularly in 3GPP Rel5 and later releases, the lack of a dedicated channel connection state leads to issues with packet reordering due to the inability of the network to maintain transmission sequence numbers (TSN) correctly across periods of inactivity, causing delays in data delivery when user equipment (UE) moves or reallocates H-RNTI, resulting in out-of-order packet reception and unnecessary reordering delays.
Innovation Solution
The introduction of additional timers, both in the UE and Node B, to reset TSN values when inactivity thresholds are reached, allowing the network to consider a UE as inactive and freeing up resources, thus simplifying TSN management and avoiding reallocation issues during mobility scenarios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the network maintains TSN history records for inactive UEs to ensure correct reordering, then packet delivery order is improved, but device complexity and memory requirements increase
Solution Approach 1:
The network side performs preliminary actions by resetting the TSN counter to a known value (zero) when a UE becomes inactive, rather than maintaining history records. This preliminary reset prevents future reordering issues without requiring complex record-keeping mechanisms.
Solution Approach 2:
The invention changes the TSN parameter state by resetting it to a known value upon UE inactivity detection. This parameter change eliminates the need to maintain historical TSN values, simplifying the system while ensuring correct reordering when the UE becomes active again.
2Device complexity
If the network resets TSN to zero for inactive UEs, then device complexity is reduced, but packet delivery time increases due to reordering delays
Solution Approach 1:
The invention implements a feedback mechanism where the network detects UE inactivity through the lack of uplink signals (pilot signals, acknowledgment signals) and responds by resetting the TSN counter. This feedback loop ensures TSN is reset at the optimal moment to minimize reordering delays while simplifying management.
Solution Approach 2:
The TSN counter management becomes dynamic rather than static - it is reset based on real-time detection of UE inactivity conditions. This dynamic approach allows the system to adapt to actual UE activity patterns, reducing both complexity and unnecessary delays.
3Measurement precision
If the network maintains dedicated TSN state for each UE in CELL_FACH state, then reordering accuracy is improved, but use of energy and system resources increases
Solution Approach 1:
The invention extracts the TSN state maintenance requirement only for active UEs. When a UE transitions to inactive state (detected through lack of uplink signals), the network releases the TSN state, taking out the resource consumption associated with maintaining it while preserving the ability to track TSN for active UEs.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The definition and use of an additional timer for the MAC-hs reordering function in a user equipment. The timer counts transmission time intervals and is reset each time that the user equipment receives a data packet. If the timer reaches a set value, indicating a sufficiently long period of inactivity, then the transmission sequence number is reset to zero or another predefined value. A base station can run a similar timer and, after the timer reaches a set value, can consider the user equipment as no longer being active.