PRACH Sequence Multiplexing for Faster Small-Packet Random Access

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Solution Overview

Problem

The transmission efficiency of small packet services in mobile communications is low due to large signaling overhead and delay in the random access process, particularly in machine-to-machine communication and smartphone applications.

Innovation Solution

A random access method where user equipment multiplexes and transmits first information, such as RRC requests or shared channels, along with the PRACH sequence to improve transmission efficiency by reducing signaling overhead and delay.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If traditional random access process is used for small packet services, then the protocol compatibility is maintained, but the transmission efficiency is low due to large signaling overhead and delay

Engineering Contradiction:
Improvetransmission efficiencyVSAvoidsignaling overhead and delay
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent merges the random access signaling with the actual data payload by allowing the UE to transmit both the random access preamble and the small packet data in a single message to the base station. This combining of previously separate transmission steps eliminates the delay between random access completion and data transmission, directly resolving the technical contradiction between maintaining protocol compatibility and improving transmission efficiency for small packets.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent enables the UE to prepare and attach the small packet data to the random access message in advance, before the traditional random access response is received. This preliminary action of bundling data with the random access request allows the data to be transmitted immediately upon random access completion, eliminating the waiting time that would otherwise occur and significantly reducing overall transmission delay.

Inventive Principle:
Principle #10Preliminary action

2Loss of time

If multiple signaling exchanges are performed sequentially, then the protocol simplicity is maintained, but the transmission time increases

Engineering Contradiction:
Improvetransmission timeVSAvoidsignaling process complexity
Core Design Contradiction:
Loss of timeVSDevice complexity

Solution Approach 1:

The patent combines multiple signaling exchanges into a single message transmission by allowing the UE to include both random access indicators and small packet data in one uplink message. This merging reduces the total number of round-trip exchanges between UE and base station, directly reducing transmission time while the structured message format keeps the implementation relatively simple.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent makes the random access message structure universal by enabling it to serve dual purposes: both as a traditional random access preamble and as a carrier for small packet data. This multi-functionality allows the same message structure to handle both purposes simultaneously, reducing the need for separate signaling messages and thereby reducing overall transmission time without requiring completely new protocol mechanisms.

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

Data Source

PatentEP3893587B1Random access method, base station, and user equipment
Publication Date: 2025.08.27 HUAWEI TECH CO LTD
  • EP3893587B1 patent drawingFigure 1~2A
  • EP3893587B1 patent drawingFigure 2B
  • EP3893587B1 patent drawingFigure 2C~2E

AI summary

The present invention provides a random access method, a base station, and a user equipment. The method includes: obtaining, by the UE, a PRACH sequence; and sending, by the UE, the PRACH sequence to the base station to perform random access, and carrying first information when sending the PRACH sequence so that the base station receives the first information in a random access process. In the technical solutions of the present invention, the UE sends the first information in the random access process, which improves transmission efficiency of the first information. The present invention is particularly applicable to services of small packets.