Dynamic Terminal Uplink Power Control Under RF Exposure Limits
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Solution Overview
Problem
Existing power control mechanisms for terminal devices in radio transmission systems face challenges in efficiently managing momentary and average power levels to comply with RF exposure regulations, particularly when dynamic power sharing between LTE and NR legs results in potential uplink transmission drops and resource wastage.
Innovation Solution
Implementing a back-off power control loop in the radio access network node and terminal device to dynamically adjust uplink power, allowing temporary increases in momentary power within regulatory limits while maintaining average power compliance, using a power regulating parameter and feedback mechanisms to ensure adherence to RF exposure standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the terminal device uses higher momentary transmit power to improve communication performance, then the throughput and data rate are improved, but the average power may exceed regulatory RF exposure limits
Solution Approach 1:
The patent applies periodic action by allowing the terminal device to transmit at higher power levels during specific time intervals (e.g., during scheduled uplink transmissions) while maintaining lower average power over longer periods. The network controller dynamically adjusts power allocation in a periodic manner based on scheduling decisions, enabling peak power usage when needed while ensuring compliance with average power limits over regulatory averaging times.
Solution Approach 2:
The patent implements dynamics by introducing dynamic power control where the terminal device adjusts its transmit power based on real-time network scheduling and channel conditions. The network controller dynamically allocates power budgets and adjusts power regulating parameters (such as P0, NOMINAL, and alpha) based on observed average power levels, allowing the system to adapt between maintaining strict average power compliance and permitting temporary power bursts for improved throughput.
2Productivity
If the terminal device increases momentary power above average limits for short durations, then communication performance improves, but compliance with average power limits becomes difficult to maintain
Solution Approach 1:
The patent applies feedback by implementing a closed-loop power control mechanism where the network controller continuously monitors the terminal device's average transmit power and adjusts power regulating parameters accordingly. When the observed average power approaches or exceeds limits, the network controller reduces the power budget or adjusts parameters to bring compliance back within limits, while still allowing temporary excursions above average limits when communication performance requires it.
Solution Approach 2:
The patent implements parameter changes by dynamically adjusting power control parameters (P0, NOMINAL, alpha, and power offsets) based on the terminal device's observed average power consumption and compliance status. These parameter changes enable the system to flexibly transition between different power operating modes, allowing higher momentary power when parameters indicate compliance headroom exists, while automatically tightening power control when average limits are approached.
3Productivity
If dynamic power sharing is implemented between LTE and NR legs, then resource utilization improves, but uplink transmission drops and resource wastage occur
Solution Approach 1:
The patent applies preliminary action by having the network controller pre-calculate and allocate power budgets to the terminal device for both LTE and NR uplink transmissions before actual transmissions occur. The controller determines appropriate power regulating parameters and power sharing ratios in advance based on channel conditions, QoS requirements, and compliance considerations, preventing transmission drops by ensuring sufficient power is allocated before needed.
Solution Approach 2:
The patent implements dynamics in power sharing by allowing the network controller to dynamically adjust the power allocation ratio between LTE and NR legs based on real-time conditions. When one leg experiences poor channel conditions or requires more power for reliable transmission, the controller dynamically shifts the power budget to that leg, preventing transmission drops while maintaining overall compliance with average power limits.
Data Source
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AI summary
There is provided mechanisms for uplink power control of a terminal device. A method is performed in a network serving the terminal device. The method comprises estimating average total uplink transmit power for the terminal device. The method comprises determining a dynamic power threshold from the average total uplink transmit power according to a back-off power control loop. In the back-off power control loop, a setpoint value of total average transmission power is compared with a value of the estimated average total uplink transmit power. The method comprises setting a value of a power regulating parameter as function of the dynamic power threshold. The method comprises providing the value of the power regulating parameter to the terminal device for uplink power control of the terminal device.