HARQ Process Flushing via Reconfiguration Flag

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

There is currently no method for the UTRAN to signal to a UE device when to perform High Speed Uplink Packet Access (HSUPA) Hybrid Automatic Repeat Request (HARQ) process flushing, which can interfere with reconfiguration procedures if not properly managed.

Innovation Solution

A method where the UTRAN includes a flag in a reconfiguration message to indicate to the UE device whether to flush its send buffers prior to reconfiguration, allowing the UE device to parse the message and perform HARQ process flushing accordingly, using an enhanced dedicated channel information element and MAC-es/e reset indicator.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If reconfiguration including DDI reconfiguration is performed before HARQ process flushing, then reconfiguration can proceed, but packet transmission may be interfered with due to re-mapping of MAC-d flows

Engineering Contradiction:
Improvereconfiguration capabilityVSAvoidpacket transmission reliability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent applies preliminary action by performing HARQ process flushing before reconfiguration. The send buffer is flushed to remove packets that could be interfered with by upcoming DDI reconfiguration and MAC-d flow re-mapping, ensuring that reconfiguration proceeds without compromising packet transmission reliability.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If HARQ process flushing is performed, then packet transmission reliability is maintained during reconfiguration, but retransmissions are lost

Engineering Contradiction:
Improvepacket transmission reliabilityVSAvoidretransmission time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent extracts and removes packets from the send buffer before reconfiguration occurs. By flushing the buffer in advance, packets that would be affected by re-mapping are removed, preventing transmission errors. The system accepts the loss of these packets (and their retransmission time) as necessary to maintain overall transmission reliability during reconfiguration.

Inventive Principle:
Principle #2Taking out (Extraction)

3Ease of operation

If there is no signaling method for HARQ process flushing, then the system remains simple, but the UTRAN cannot control buffer flushing during reconfiguration

Engineering Contradiction:
Improvebuffer flushing controlVSAvoidsignaling mechanism complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The patent makes the existing reconfiguration message multi-functional by adding a buffer flushing indicator field to it. This existing message structure, already used for DDI reconfiguration, now also serves to trigger HARQ process flushing. This approach provides the necessary control capability while minimizing additional signaling complexity by reusing an existing message format.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP1946473B1Hsupa HARQ process flushing
Publication Date: 2013.12.04 NOKIA CORP
  • EP1946473B1 patent drawingFigure 1~2
  • EP1946473B1 patent drawingFigure 3
  • EP1946473B1 patent drawingFigure 4A~4C

AI summary

A method and equipment by which a radio access network (e.g. UTRAN) of a wireless network (e.g. UMTS) communicates to a user equipment wireless communication device (e.g. a mobile station) an indication that the user equipment is to flush one or more send buffers, e.g. buffers used by HARQ processes, such as for HSUPA. A flag is included in a message to indicate that the one or more send buffers are to be flushed. The message is for example a message indicating reconfiguration is to be performed, and the flag (if set) is to be interpreted by the user equipment as indicating that the one or more send buffers are to be flushed prior to performing the reconfiguration. A corresponding method and equipment for a user equipment wireless communication device are also provided.