MAC CE Bearer Mapping for NR Repeat Transmission Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In the 5G New Radio (NR) system, different network nodes transmitting conflicting activation/deactivation retransmission MAC CEs leads to erroneous operations at the user equipment (UE), as current mechanisms lack coordination between network nodes for managing retransmission bearers.

Innovation Solution

A method where base stations configure a correspondence relationship between bearers allowed for retransmission and bits in the MAC CE, ensuring only valid retransmission indications are made for local bearers, and the UE parses these indications correctly to avoid misunderstandings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If repeat transmission is continuously performed to ensure reliable data delivery, then reliability is improved, but power consumption increases and battery life decreases

Engineering Contradiction:
Improvedata delivery reliabilityVSAvoidterminal power consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent implements dynamic adjustment of repeat transmission parameters based on channel conditions. The base station configures different repeat transmission modes (e.g., adaptive repeat, selective repeat) and the terminal adapts its transmission behavior according to received signal quality feedback, transitioning between active transmission and idle states to optimize power consumption while maintaining reliability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes transmission parameters such as repeat transmission count, time interval between repeats, and transmission power dynamically. The base station configures parameters like maximum repeat count and time window, while the terminal adjusts actual transmission based on channel quality metrics, thereby balancing reliability requirements with power consumption constraints.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If repeat transmission is activated to improve communication reliability in poor channel conditions, then reliability is improved, but device complexity increases due to additional configuration and control mechanisms

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidrepeat transmission control complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent integrates repeat transmission functionality into the existing uplink scheduling framework. The same physical uplink shared channel (PUSCH) resources are reused for both initial transmission and repeat transmission, and the control signaling leverages existing downlink control information (DCI) formats. This multi-functional approach avoids creating separate complex control mechanisms while achieving reliable communication.

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

Solution Approach 2:

The base station acts as an intermediary that configures repeat transmission parameters through standardized RRC signaling and DCI formats. Rather than requiring complex terminal-side autonomous decisions, the base station mediates the control process by providing configuration parameters (e.g., repeat count, time window, resource allocation) that simplify terminal implementation while maintaining system-wide optimization.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If repeat transmission uses dedicated resources to ensure reliable delivery, then reliability is improved, but resource utilization efficiency decreases

Engineering Contradiction:
Improvedata transmission reliabilityVSAvoidresource utilization efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent merges repeat transmission resources with normal uplink data transmission resources. The base station allocates PUSCH resources that can serve both initial transmission and repeat transmission purposes. When repeat transmission is configured, the same or overlapping time-frequency resources are reused, eliminating the need for separate dedicated repeat resources and improving overall resource utilization efficiency.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The system allocates resources with partial redundancy in mind. The base station configures maximum repeat count and time window parameters that define potential resource usage, but actual resource consumption depends on channel conditions. This allows the system to prepare for reliable transmission while only consuming additional resources when necessary, thereby improving average resource utilization efficiency.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP3661101B1Method for activating/deactivating repeat transmission, base station, terminal and device
Publication Date: 2026.05.06 DATANG MOBILE COMM EQUIP CO LTD
  • EP3661101B1 patent drawingFigure 1~2
  • EP3661101B1 patent drawingFigure 3~4
  • EP3661101B1 patent drawingFigure 5~6

AI summary

The present disclosure provides a retransmission activating/deactivating method, a base station, a user equipment and a device. The method includes: determining a correspondence relationship between a bearer which is allowed for retransmission under the first base station and a bit of a preset field of media access control (MAC) control element (CE) of the first base station for activating/deactivating retransmission; where the preset field is used to indicate activation/deactivation retransmission of the bearer which is allowed for retransmission; and, when determining to activate/deactivate retransmission of the bearer which is allowed for retransmission under the first base station, populating, by the first base station, the bit, which is in the preset field of the MAC CE for activating/deactivating retransmission and corresponding to the bearer, thereby generating the MAC CE for activating/deactivating retransmission, and transmitting to the UE the generated MAC CE for activating/deactivating retransmission.