Random Access PUSCH DMRS Alignment for Reliable Message Detection

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Solution Overview

Problem

Uplink transmission failures occur during random access processes in 5G NR systems due to the network device's inability to detect the DMRS sequence of the terminal's PUSCH, leading to unsuccessful detection of the random access message (msgA) and increased detection complexity.

Innovation Solution

The terminal generates and sends a random access message using a DMRS sequence based on a specific generation parameter, ensuring the network device can demodulate the PUSCH correctly, thereby improving data detection success rates and reducing unnecessary blind detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the terminal sends a random access message on PUSCH in an asynchronous state during non-contention-based random access, then uplink data transmission can be initiated, but the network device cannot detect the message because it cannot obtain the DMRS sequence

Engineering Contradiction:
Improverandom access efficiencyVSAvoidmessage detection success rate
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The network device pre-configures and provides the terminal with DMRS sequence generation parameters before the terminal sends the random access message. This preliminary action ensures that the terminal can generate the correct DMRS sequence for PUSCH transmission, enabling the network device to successfully detect and demodulate the random access message without requiring additional blind detection attempts.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If the network device performs blind detection to find the DMRS sequence for PUSCH, then it may eventually detect the message, but the detection complexity increases significantly

Engineering Contradiction:
Improvemessage detection capabilityVSAvoiddetection complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The terminal autonomously generates the DMRS sequence using the pre-configured generation parameters provided by the network device, rather than relying on the network device to perform complex blind detection. This self-service approach allows the terminal to prepare the correct reference signal in advance, making the network device's detection task straightforward and reducing overall system complexity.

Inventive Principle:
Principle #25Self-service

3Use of energy by moving object

If the terminal uses asynchronous transmission for small uplink data packets, then resource and power consumption are reduced, but uplink timing synchronization is lost

Engineering Contradiction:
Improvepower consumptionVSAvoidtiming synchronization
Core Design Contradiction:
Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The network device provides DMRS sequence generation parameters to the terminal in advance, before the terminal enters asynchronous transmission mode. This preliminary configuration enables the terminal to maintain the ability to generate correct reference signals even when operating asynchronously, allowing the network device to successfully detect and synchronize with the terminal's transmissions without requiring continuous timing synchronization.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3914021B1Random access transmission method and terminal
Publication Date: 2025.11.05 VIVO MOBILE COMM CO LTD
  • EP3914021B1 patent drawingFigure 1~3
  • EP3914021B1 patent drawingFigure 4~5
  • EP3914021B1 patent drawing

AI summary

This application discloses a random access transmission method and a terminal. The method includes: obtaining a demodulation reference signal DMRS sequence generation parameter of a physical uplink shared channel PUSCH; and sending a random access message according to the DMRS sequence generation parameter; where the random access message corresponds to the PUSCH and a PRACH.