PUCCH Repetition HARQ-ACK Codebook Determination

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In LTE and NR systems, the proper transmission of Uplink Control Information (UCI) using Physical Uplink Control Channel (PUCCH) repetition is hindered by unclarified restrictions, leading to potential deterioration in communication throughput and frequency utilization efficiency due to unclear behaviors of UEs and base stations regarding HARQ-ACK repetitions and PUCCH overlap.

Innovation Solution

The proposed solution involves configuring PUCCH repetitions with specific restrictions and assumptions for UEs, such as non-overlapping slots for certain UCI types and dynamic HARQ-ACK codebooks, to ensure proper UCI transmission, even when PUCCH repetitions occur.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If PUCCH repetition is used for UCI transmission, then transmission reliability is improved, but system complexity increases due to unclarified restrictions and behaviors

Engineering Contradiction:
ImproveUCI transmission reliabilityVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by defining specific parameters for PUCCH repetition behavior, including the relationship between PDSCH reception timing and PUCCH transmission timing, the number of repetitions, and slot allocation. These parameter definitions clarify the previously unclarified restrictions and enable reliable UCI transmission through structured control mechanisms.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If HARQ-ACK repetitions for different PDSCHs are allowed to overlap in one slot, then communication throughput is improved, but transmission reliability deteriorates due to potential conflicts and interference

Engineering Contradiction:
Improvecommunication throughputVSAvoidtransmission reliability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by establishing advance rules for determining PUCCH transmission timing based on PDSCH reception timing. The UE determines the slot offset K1 and calculates PUCCH transmission slots before actual transmission occurs. This preliminary determination prevents conflicts and interference by ensuring proper timing relationships are maintained, even when multiple HARQ-ACK repetitions are scheduled.

Inventive Principle:
Principle #10Preliminary action

3Adaptability or versatility

If restrictions on PUCCH repetition are not clearly defined, then adaptability is improved, but manufacturing precision deteriorates due to inconsistent UE and base station behaviors

Engineering Contradiction:
Improvesystem adaptabilityVSAvoidbehavior consistency
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent defines specific parameters including slot offset K1, number of repetitions, and timing relationships between PDSCH and PUCCH. These parameter definitions provide consistent behavior rules for both UE and base station while maintaining adaptability through configurable values. The standardized parameter framework ensures precise and consistent implementation across different devices and scenarios.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3832928B1User terminal and wireless communication method
Publication Date: 2025.06.25 NTT DOCOMO INC
  • EP3832928B1 patent drawingFigure 1
  • EP3832928B1 patent drawingFigure 2
  • EP3832928B1 patent drawingFigure 3

AI summary

According to one aspect of the present disclosure, a user terminal includes a control section that determines, when an uplink control channel (PUCCH) repetition and a dynamic hybrid automatic repeat reQuest acknowledgement (HARQ-ACK) codebook are configured, a codebook for PUCCH transmission per slot based on at least one of a total downlink assignment index (T-DAI), a counter downlink assignment index (C-DAI), a timing from reception of a physical downlink shared channel (PDSCH) to transmission of the HARQ-ACK corresponding to the PDSCH and repetition factor, and a transmitting section that transmits HARQ-ACK based on the codebook by applying PUCCH repetition to the HARQ-ACK. According to one aspect of the present disclosure, it is possible to appropriately transmit the UCI even when the PUCCH repetition is used.