UE Context Preservation for Low-Energy Harvesting Wireless Nodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Energy harvesting wireless devices face challenges in maintaining communication due to low energy levels, leading to excessive signaling and energy consumption when batteries need frequent recharging or replacement, especially in IoT devices placed in hard-to-reach locations with limited battery capacity.
Innovation Solution
A method where the network node and energy harvesting wireless device collaborate to preserve the UE context during low energy conditions, allowing the device to inform the network of insufficient power levels and delaying registration procedures until sufficient energy is harvested, reducing latency and energy consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the device performs regular registration procedures when energy is sufficient, then communication connectivity is maintained, but energy consumption increases and latency occurs during low energy conditions
Solution Approach 1:
The device performs a preliminary indication action by sending a message to the network node before the low energy condition causes communication failure. This preliminary action informs the network to preserve the UE context, preventing the need for full registration procedures later and reducing energy consumption when the device resumes communication.
Solution Approach 2:
The device dynamically adjusts its communication behavior based on energy availability. When energy is sufficient, normal registration procedures are performed. When energy becomes insufficient, the device transitions to a low-power mode where it sends an indication message and allows the network to preserve context, thereby adapting to changing energy conditions without losing connectivity.
2Reliability
If the device sends frequent registration requests during low energy conditions, then connectivity is maintained, but signaling overhead and latency increase
Solution Approach 1:
The device sends a preliminary indication message to the network node before connectivity is lost, informing the network to preserve the UE context. This preliminary action prevents the need for repeated registration requests and full registration procedures when the device resumes communication, significantly reducing latency.
Solution Approach 2:
The network node acts as an intermediary by preserving the UE context during the device's low energy period. This intermediary action allows the device to resume communication quickly without needing to re-establish the full context, reducing the time loss associated with repeated registration procedures.
3Reliability
If the device performs full registration procedures upon resuming communication, then connectivity is restored, but energy consumption and latency increase
Solution Approach 1:
The device performs a preliminary indication action by sending a message to the network node before entering low energy condition, informing the network to preserve the UE context. This preliminary action enables the device to resume communication with a simplified procedure rather than a full registration, reducing energy drain.
Solution Approach 2:
Instead of discarding the UE context during low energy conditions, the network preserves it based on the device's indication message. This recovery of the preserved context allows the device to restore connectivity without performing energy-intensive full registration procedures.
Data Source
AI summary
A method is disclosed, performed by a network node, for handling low energy conditions of an energy harvesting wireless device. WD, wherein the network node has a UE context of the WD received in a registration procedure stored. The method comprises receiving, from the WD, a message indicating that the WD has insufficient power level for performing regular radio operation for upcoming message exchange and indicating that the UE context of the WD is to be preserved for a time period during which the power level is insufficient.