Inactive-State Uplink Data Transmission Without RRC Reconnection

Solution Overview

Problem

Existing communication protocols for user equipment (UE) in RRC_IDLE or RRC_INACTIVE states require transitioning to RRC_CONNECTED state for multiple data packet transmissions, leading to increased battery consumption and resource allocation, especially when handling small packets.

Innovation Solution

UE initiates early data transmission by sending multiple data packets in uplink using security-protected UL RRC messages or MAC PDUs without transitioning to RRC_CONNECTED state, allowing base stations to apply security functions and forward data to the core network.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If UE transitions to RRC_CONNECTED state for multiple data packet transmissions, then data transmission capability is improved, but battery consumption and resource allocation increase

Engineering Contradiction:

Improvedata transmission capabilityVSAvoidbattery consumption

Core Design Contradiction:

ProductivityVSUse of energy by moving object

Solution Approach 1:

The patent applies preliminary action by enabling the UE to transmit multiple data packets in advance while in the RRC_INACTIVE state, before transitioning to RRC_CONNECTED. The UE initiates early data transmission with multiple packets included in the initial UL RRC message or subsequent MAC PDUs, thereby avoiding the need to enter connected state for each transmission and reducing battery consumption associated with connected state maintenance.

Inventive Principle:

Principle #10Preliminary action

2Productivity

If UE transitions to RRC_CONNECTED state for multiple data packet transmissions, then data transmission capability is improved, but air interface resource usage increases

Engineering Contradiction:

Improvedata transmission capabilityVSAvoidair interface resource usage

Core Design Contradiction:

ProductivityVSQuantity of substance

Solution Approach 1:

The patent applies preliminary action by enabling the UE to transmit multiple data packets in advance while in the RRC_INACTIVE state, before transitioning to RRC_CONNECTED. The UE initiates early data transmission with multiple packets included in the initial UL RRC message or subsequent MAC PDUs, thereby avoiding the need to enter connected state for each transmission and reducing battery consumption associated with connected state maintenance.

Inventive Principle:

Principle #10Preliminary action

3Use of energy by moving object

If UE transmits multiple data packets in RRC_INACTIVE state, then battery consumption is reduced, but protocol complexity increases

Engineering Contradiction:

Improvebattery consumptionVSAvoidprotocol complexity

Core Design Contradiction:

Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The patent applies universality by designing the early data transmission mechanism to handle multiple data packets using the same RRC_INACTIVE state procedures. The UE can include multiple packets in the initial transmission or use subsequent MAC PDUs with the same security context and inactive state management, thereby reducing battery consumption without requiring entirely new protocol mechanisms for each packet.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent introduces an intermediary mechanism where the gNB stores multiple packets received from the UE in inactive state and forwards them to the core network after the UE transitions to connected state. This intermediary buffering approach allows the UE to transmit multiple packets while inactive, reducing its energy consumption, while the gNB handles the complexity of protocol management and packet forwarding.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS12574723B2Early data communication in an inactive state

Publication Date: 2026.03.10 GOOGLE LLC

AI summary

To perform early data transmission with a radio access network (RAN), a UE transmits, by processing hardware and when a radio connection between the UE and the RAN is inactive, an initial data packet to the RAN (1306). The UE transmits, by the processing hardware subsequent to transmitting the initial data packet and while the radio connection remains inactive, a subsequent data packet to the RAN (1308).