HARQ Process Identifier Assignment for Semi-Persistent Resource Mapping

Solution Overview

Problem

In mobile communication systems supporting Hybrid Automatic Repeat reQuest (HARQ), the use of semi-persistent resources for VoIP packets leads to challenges in soft-combining retransmitted packets without resource allocation information, resulting in errors and unnecessary retransmissions due to unclear packet mapping during HARQ operations.

Innovation Solution

A method is introduced to assign a HARQ process identifier and soft-buffer size during call setup, allowing for correct identification and soft-combination of retransmitted packets by mapping semi-persistent resource allocations to specific HARQ processes using time information and retransmission numbers, thereby preventing errors and unnecessary retransmissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of information

If semi-persistent resources are used for HARQ initial transmission without resource allocation information, then resource allocation overhead is reduced, but packet mapping accuracy deteriorates leading to soft-combining errors

Engineering Contradiction:

Improveresource allocation informationVSAvoidpacket mapping accuracy

Core Design Contradiction:

Loss of informationVSReliability

Solution Approach 1:

The patent applies preliminary action by pre-configuring HARQ process identifiers and soft-buffer sizes during call setup for semi-persistent resources. This allows the UE to correctly identify and map retransmitted packets to the appropriate HARQ processes without requiring resource allocation information in each transmission, thereby resolving the contradiction between reducing information overhead and maintaining packet mapping accuracy

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces HARQ process identifiers as an intermediary mechanism that bridges the gap between semi-persistent resource allocations and packet mapping. These identifiers act as mediators that enable correct soft-combining of retransmitted packets without requiring full resource allocation information, thus solving the contradiction between information reduction and mapping reliability

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If semi-persistent resources are allocated periodically, then resource allocation overhead is reduced, but packet identification reliability deteriorates due to unclear packet mapping

Engineering Contradiction:

Improveresource allocation efficiencyVSAvoidpacket identification reliability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by pre-configuring multiple HARQ process identifiers and their corresponding soft-buffer sizes during call setup for semi-persistent resources. This allows the UE to correctly identify and map retransmitted packets to the appropriate HARQ processes without requiring resource allocation information in each transmission, thereby resolving the contradiction between reducing information overhead and maintaining packet mapping accuracy

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces HARQ process identifiers as an intermediary mechanism that bridges the gap between semi-persistent resource allocations and packet mapping. These identifiers act as mediators that enable correct soft-combining of retransmitted packets without requiring full resource allocation information, thus solving the contradiction between information reduction and mapping reliability

Inventive Principle:

Principle #24Intermediary (Mediator)

3Loss of information

If HARQ process identifier is not transmitted in semi-persistent resources, then control information overhead is reduced, but soft-combining accuracy deteriorates due to inability to map retransmitted packets

Engineering Contradiction:

Improvecontrol informationVSAvoidsoft-combining accuracy

Core Design Contradiction:

Loss of informationVSMeasurement precision

Solution Approach 1:

The patent applies preliminary action by pre-configuring HARQ process identifiers and soft-buffer sizes during call setup for semi-persistent resources. This allows the UE to correctly identify and map retransmitted packets to the appropriate HARQ processes without requiring resource allocation information in each transmission, thereby resolving the contradiction between reducing information overhead and maintaining packet mapping accuracy

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces HARQ process identifiers as an intermediary mechanism that bridges the gap between semi-persistent resource allocations and packet mapping. These identifiers act as mediators that enable correct soft-combining of retransmitted packets without requiring full resource allocation information, thus solving the contradiction between information reduction and mapping reliability

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUSRE50056E1Apparatus and method for transmitting and receiving packets in a mobile communication system supporting hybrid automatic repeat request

Publication Date: 2024.07.23 SAMSUNG ELECTRONICS CO LTD

AI summary

An apparatus and a method are provided for operating HARQ in a mobile communication system. The method includes receiving a number of HARQ processes of a semi-persistent resource allocation and semi-persistent resource allocation interval information for a first transmission; receiving data in the first transmission at a subframe based on the semi-persistent resource allocation interval information; calculating a HARQ process IDentifier (ID) using the number of HARQ processes of the semi-persistent resource allocation, the semi-persistent resource allocation interval information, and time information; receiving control information including the HARQ process ID on an L1 control channel; receiving data in a retransmission based on the control information including the HARQ process ID; combining the data received in the first transmission and the data received in the retransmission; and decoding the combined data.