SIB1 PDSCH Frequency Mapping to Reduce eRedCap UE Complexity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

eRedCap UEs face ambiguity in receiving PDSCH for SIB1 due to their limited bandwidth, leading to increased UE complexity through post-FFT RE buffering for the entire 20 MHz band.

Innovation Solution

Determine the frequency band for PDSCH based on DCI, CORESET configured by MIB, or SSB, allowing eRedCap UEs to receive PDSCH within a smaller bandwidth, reducing the need for post-FFT RE buffering across the entire 20 MHz.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If eRedCap UE performs post-FFT RE buffering for 20 MHz to receive SIB1, then SIB1 reception is ensured, but UE complexity increases

Engineering Contradiction:
ImproveSIB1 receptionVSAvoidUE complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts only the necessary portion of the 20 MHz bandwidth that the eRedCap UE needs to receive PDSCH for SIB1. Instead of buffering the entire 20 MHz, the UE determines a specific frequency band (e.g., 5 MHz) within the 20 MHz based on DCI, CORESET, or SSB information, and performs post-FFT RE buffering only for this extracted subset, thereby reducing complexity while ensuring reliable SIB1 reception.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies local quality by making the buffering operation localized to a specific frequency region rather than global. The eRedCap UE identifies a particular frequency band (local region) within the 20 MHz spectrum where the PDSCH is transmitted and performs buffering only in this local area, optimizing resource usage and reducing overall UE complexity.

Inventive Principle:
Principle #3Local quality

2Device complexity

If eRedCap UE supports only 5 MHz bandwidth for PDSCH, then UE complexity is reduced, but frequency resource utilization is limited

Engineering Contradiction:
ImproveUE complexityVSAvoidfrequency resource utilization
Core Design Contradiction:
Device complexityVSProductivity

Solution Approach 1:

The patent resolves this contradiction by introducing a temporal dimension to bandwidth adaptation. The eRedCap UE can operate with 5 MHz bandwidth for normal PDSCH reception, but can access up to 20 MHz bandwidth for specific broadcast PDSCH transmissions during initial connection. This time-based bandwidth switching allows the system to optimize between complexity and resource utilization dynamically.

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

Data Source

PatentEP4598137A1Method for transmitting and receiving system information and device thereof in wireless communication system
Publication Date: 2025.08.06 LG ELECTRONICS INC
  • EP4598137A1 patent drawingFigure 1
  • EP4598137A1 patent drawingFigure 2
  • EP4598137A1 patent drawingFigure 3~4

AI summary

A method performed by a terminal according to an embodiment of the present disclosure comprises the steps of: receiving an MIB from a base station; receiving a PDCCH from the base station on the basis of the MIB; and receiving a PDSCH from the base station. The PDSCH is related to an SIB1. A frequency band related to the PDSCH is determined on the basis of i) DCI, ii) a control resource set (CORESET) configured on the basis of the MIB, or iii) a synchronization signal/physical broadcast channel block (SSB).