HARQ-ACK Resource Mapping for 5G Uplink Performance

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Solution Overview

Problem

In 5G networks, the concentration of HARQ-ACK modulation symbols on specific OFDM symbols during multiplexing with uplink data leads to performance degradation in uplink data transmission, as existing resource mapping methods from LTE systems are not effective in distributing these symbols uniformly across frequency domains.

Innovation Solution

A physical-layer resource mapping method that determines a starting position and frequency-domain offset for HARQ-ACK modulation symbols to evenly distribute them across multiple OFDM symbols, preventing concentration and thus reducing performance degradation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If HARQ-ACK modulation symbols are mapped to four OFDM symbols next to DMRS symbols in time domain (LTE manner), then the mapping process is simple, but the symbols become concentrated on specific OFDM symbols causing uplink data transmission performance degradation

Engineering Contradiction:
Improvemapping process simplicityVSAvoiduplink data transmission performance
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent transitions from time-domain-first mapping (LTE approach) to frequency-domain-first mapping (5G NR approach). Instead of mapping HARQ-ACK symbols sequentially in time domain and then frequency domain, the invention maps them first in frequency domain across multiple physical resource blocks, then distributes them across time domain, achieving both simplicity and performance

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent changes the mapping parameter sequence from time-domain-first to frequency-domain-first. By altering the primary mapping dimension from time to frequency, the invention achieves uniform distribution of HARQ-ACK symbols across multiple OFDM symbols while maintaining mapping process simplicity through the established frequency-domain resource allocation framework

Inventive Principle:
Principle #35Parameter changes

2Productivity

If HARQ-ACK modulation symbols are concentrated on one or more specific OFDM symbols, then resource allocation is efficient, but uplink data transmission performance deteriorates due to error detection issues

Engineering Contradiction:
Improveresource allocation efficiencyVSAvoiduplink data transmission performance
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent segments the HARQ-ACK modulation symbols across multiple frequency resources (physical resource blocks) rather than concentrating them on single time-domain resources. Each symbol is mapped to different frequency positions, creating spatial distribution that prevents concentration effects while maintaining efficient resource utilization

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention shifts the distribution strategy from time-domain concentration to frequency-domain distribution. By mapping symbols across multiple physical resource blocks in frequency domain first, the patent achieves both efficient resource allocation and prevents the performance degradation caused by temporal concentration

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP3706482B1Physical layer resource mapping method and device, user equipment and base station
Publication Date: 2024.01.03 BEIJING XIAOMI MOBILE SOFTWARE CO LTD
  • EP3706482B1 patent drawingFigure 1A~1B
  • EP3706482B1 patent drawingFigure 1C
  • EP3706482B1 patent drawingFigure 2A~2B

AI summary

Provided are physical-layer resource mapping methods and devices, UE and a base station. The method includes: during multiplexing transmission of hybrid automatic repeat request acknowledgement (HARQ ACK) information and uplink data, determining a starting position and frequency-domain offset of an HARQ-ACK modulation symbols mapped to a physical-layer resource, the frequency-domain offset being each of frequency-domain offsets of resource elements (REs) that different HARQ-ACK modulation symbols are mapped to; and mapping each HARQ-ACK modulation symbol to the corresponding RE according to the starting position and the frequency-domain offset. Accordingly, the HARQ-ACK modulation symbols may be uniformly distributed to as many orthogonal frequency division multiplexing (OFDM) symbols as possible preferably in a frequency domain in a manner of time domain first, and uplink data transmission performance reduction caused by concentrated distribution of the HARQ-ACK modulation symbol on one or more OFDM symbols can be avoided.