MAC Layer Reset for System Information Acquisition in 5G UE

Solution Overview

Problem

In 5G wireless communication systems, user equipment (UE) faces challenges in correctly acquiring system information due to radio link environment instability, particularly when no acknowledgment is received from the network side, leading to repeated preamble transmissions.

Innovation Solution

A method and apparatus for resetting the Medium Access Control (MAC) layer in UE when system information is unsuccessfully requested, including resetting the MAC layer if no acknowledgment is received within a predefined time period or if a random access problem occurs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the UE repeatedly transmits the preamble to request system information, then the probability of successfully acquiring system information increases, but the time consumption and resource utilization deteriorate

Engineering Contradiction:

Improvesystem information acquisition success rateVSAvoidtime consumption for repeated transmissions

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by resetting the MAC layer before the UE exhausts all transmission opportunities. When the timer expires without receiving system information, the MAC layer is reset to clear previous transmission states and reinitialize random access parameters, enabling the UE to start fresh with new preamble transmissions rather than continuing futile repetitions

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements feedback through the timer mechanism that monitors the duration of system information request. When the timer expires without successful acquisition, the system triggers MAC layer reset as a feedback response, indicating that the current transmission approach has been unsuccessful for too long and a state reset is needed

Inventive Principle:

Principle #23Feedback

2Reliability

If the UE continues to transmit preamble after maximum transmissions are reached, then system information may be acquired, but the radio link resources are wasted

Engineering Contradiction:

Improvesystem information acquisitionVSAvoidradio link resource consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The patent applies preliminary action by resetting the MAC layer before the UE exhausts all transmission opportunities. When the timer expires without receiving system information, the MAC layer is reset to clear previous transmission states and reinitialize random access parameters, enabling the UE to start fresh with new preamble transmissions rather than continuing futile repetitions

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes parameters by resetting the MAC layer state, which includes clearing transmission counters, resetting random access parameters, and reinitializing the timer. This parameter reset allows the UE to attempt system information acquisition with fresh parameters rather than continuing with exhausted transmission states

Inventive Principle:

Principle #35Parameter changes

3Stability of the object's composition

If the MAC layer is not reset, then the transmission state is maintained, but the UE cannot recover from transmission failures in unstable radio environments

Engineering Contradiction:

Improvetransmission state consistencyVSAvoidsystem information acquisition success

Core Design Contradiction:

Stability of the object's compositionVSReliability

Solution Approach 1:

The patent applies preliminary action by resetting the MAC layer before the UE exhausts all transmission opportunities. When the timer expires without receiving system information, the MAC layer is reset to clear previous transmission states and reinitialize random access parameters, enabling the UE to start fresh with new preamble transmissions rather than continuing futile repetitions

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces dynamics by making the MAC layer state changeable through reset operations. The MAC layer transitions from a persistent state to a dynamic state that can be reinitialized based on timer expiration or transmission failure conditions, allowing the system to adapt to unstable radio environments

Inventive Principle:

Principle #15Dynamics

Data Source

PatentEP3664511B1Method and device for resetting media access control layer

Publication Date: 2025.02.19 SHARP KK

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AI summary

The present disclosure provides a method for resetting a medium access control (MAC) layer at user equipment (UE). The method comprises transmitting a system information request message for requesting system information to a network side through a random access procedure; and resetting the MAC layer when the system information is unsuccessfully requested. Embodiments of the present disclosure further provide a corresponding apparatus.