HARQ Process ID Reservation for Semi-Persistent Scheduling Throughput

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Solution Overview

Problem

In wireless telecommunications, the ambiguity in linking initial and retransmitted data packets using HARQ process IDs in semi-persistent scheduling leads to inefficiencies, particularly due to the limited number of HARQ resources, resulting in reduced peak data throughput.

Innovation Solution

Reserving a single HARQ process for initial and retransmitted data packets until a third retransmission is anticipated, then dynamically switching to a second HARQ process to avoid unnecessary resource reservation and maximize data throughput.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single HARQ process is reserved for semi-persistent scheduling to ensure packet association clarity, then reliability of packet linkage is improved, but productivity (data throughput) deteriorates due to unnecessary resource reservation

Engineering Contradiction:
Improvepacket association clarityVSAvoiddata throughput
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies dynamics by transitioning from a static HARQ process reservation approach to a dynamic one. The system dynamically selects between using a reserved HARQ process ID and a dynamically allocated HARQ process ID based on whether retransmissions are needed. This dynamic adaptation allows the system to maintain packet association clarity when necessary while maximizing data throughput when retransmissions are not required, thereby resolving the contradiction between reliability and productivity.

Inventive Principle:
Principle #15Dynamics

2Reliability

If multiple HARQ processes are reserved to handle rare third retransmissions, then reliability of handling edge cases is improved, but device complexity increases due to additional resource management

Engineering Contradiction:
Improvehandling of rare retransmissionsVSAvoidHARQ resource management
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the handling of rare third retransmissions from the standard HARQ process by introducing a separate, dedicated HARQ process specifically for this edge case. Instead of reserving multiple HARQ processes for all scenarios, the system uses a single reserved process ID for common semi-persistent scheduling and only invokes the additional process when a third retransmission is anticipated. This extraction approach maintains reliability for edge cases while minimizing the impact on device complexity.

Inventive Principle:
Principle #2Taking out (Extraction)

3Reliability

If HARQ resources are reserved conservatively to ensure all retransmission scenarios are covered, then reliability of retransmission handling is improved, but loss of time increases due to unused resource reservations

Engineering Contradiction:
Improveretransmission handlingVSAvoidresource reservation overhead
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent applies partial action by reserving HARQ resources only to the extent necessary for typical semi-persistent scheduling operations, rather than over-reserving for all possible scenarios. The system uses a single reserved HARQ process ID for normal operations and only activates additional reserved resources when specific conditions (third retransmission anticipation) are met. This partial reservation approach ensures reliable retransmission handling for common cases while minimizing time loss from unused resource reservations.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP2663012B1Signaling reserved for hybrid automatic repeat request information for downlink semi-persistent scheduling
Publication Date: 2019.05.22 BLACKBERRY LTD
  • EP2663012B1 patent drawingFigure 1
  • EP2663012B1 patent drawingFigure 2
  • EP2663012B1 patent drawingFigure 3

AI summary

A user equipment, network node and method for reuse of one of a plurality of hybrid automatic repeat request (HARQ) Process identifier (ID), the method comprising: receiving signaling at a user equipment; reserving, by the user equipment, at least one of the plurality of HARQ Process IDs for semi-persistent scheduling (SPS) based upon the signaling; determining, by the user equipment, allocation of a semi-persistent resource; associating, by the user equipment, the at least one of the plurality of HARQ Process IDs with the semi-persistent resource; and receiving, by the user equipment, a non-semi-persistent data communication utilizing the at least one of the plurality of HARQ Process IDs.