MAC Layer Segmentation for 5G NR Processing Speed

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current radio protocols face challenges in efficient real-time segmentation and re-transmissions due to tight coupling between RLC and MAC layers, which hinders pre-processing of packets and increases processing time, especially in high-bit-rate scenarios like 5G NR, leading to suboptimal ARQ operations and hardware-based processing limitations.

Innovation Solution

A method where MAC entities segment MAC SDUs without altering the RLC header's length field, allowing for pre-generation of MAC PDUs and headers before scheduling decisions, enabling efficient segmentation and re-transmissions while maintaining layer separation and hardware-based processing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If segmentation is performed in RLC layer with tight coupling between RLC and MAC layers, then real-time processing requirements are met, but processing time increases and pre-processing of packets is hindered

Engineering Contradiction:
Improveprocessing speedVSAvoidprocessing time
Core Design Contradiction:
SpeedVSLoss of time

Solution Approach 1:

The patent segments the RLC PDU into multiple MAC SDUs at the MAC layer, allowing the RLC layer to work with complete PDUs while MAC handles the segmentation. This separation enables parallel processing and pre-generation of MAC PDUs without waiting for scheduling decisions, thus reducing processing time while maintaining real-time requirements.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

MAC PDUs and headers are pre-generated before scheduling decisions are made. The MAC layer can prepare segmented SDUs in advance, and the RLC layer can compose complete PDUs beforehand, enabling hardware-based processing without software intervention during critical real-time intervals.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If tight coupling between RLC and MAC layers is maintained for real-time segmentation, then layer integration is preserved, but hardware-based processing is limited and processing complexity increases

Engineering Contradiction:
Improvelayer integrationVSAvoidprocessing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The segmentation function is extracted from the RLC layer and placed in the MAC layer. This allows RLC to maintain its error correction and reassembly functions while MAC handles segmentation, enabling independent hardware implementation of each layer without complex inter-layer coupling.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces an intermediary mechanism where the RLC header's length field is preserved unchanged, serving as a mediator between RLC and MAC layers. This allows MAC to perform segmentation without altering RLC structure, maintaining layer separation and enabling hardware-based processing while preserving protocol integrity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of information

If RLC header length field is modified during MAC segmentation, then segmentation information is preserved, but layer separation is violated and hardware processing is compromised

Engineering Contradiction:
Improvesegmentation informationVSAvoidhardware processing capability
Core Design Contradiction:
Loss of informationVSDevice complexity

Solution Approach 1:

The RLC header length field serves as an intermediary that preserves segmentation information indirectly. By keeping the length field unchanged, the patent maintains RLC layer integrity while MAC layer handles segmentation through its own mechanisms, allowing hardware-based processing without violating layer separation.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent creates a copy of the RLC PDU structure at the MAC layer, where MAC SDUs are segmented copies of the original RLC PDU segments. This copying approach preserves segmentation information in MAC headers while leaving RLC headers unchanged, enabling hardware processing without modifying RLC layer structure.

Inventive Principle:
Principle #26Copying

Data Source

PatentEP3469749B1Real-time segmentation
Publication Date: 2023.05.03 NOKIA SOLUTIONS & NETWORKS OY
  • EP3469749B1 patent drawingFigure 1
  • EP3469749B1 patent drawingFigure 2
  • EP3469749B1 patent drawingFigure 3

AI summary

The present invention provides apparatuses, methods, computer programs, computer program products and computer-readable media regarding real-time segmentation. The present invention comprises composing, on a first layer, a first layer packet data unit, PDU, having a predetermined length, including a plurality of first layer service data units, SDUs, each of the plurality of first layer SDUs including a header indicating a length of each of the first layer SDUs, and inserting a certain number of the plurality of the first layer SDUs into the first layer PDU corresponding to the predetermined length of the first layer PDU, if it is determined that a last one of the certain number of the plurality of first layer SDUs does not fit completely into the first layer PDU, segmenting the last one of the certain number of the plurality of first layer SDUs according to the predetermined length of the first layer PDU, and inserting a first part of the segmented first layer SDU into the first layer PDU, wherein the header indicates the length of the first layer.