DRX Mode Switching for Unlicensed Band Terminal Power Reduction
Solution Overview
Problem
In wireless communication technologies, especially in unlicensed bands, continuous channel monitoring by terminal devices leads to high power consumption and reduced battery life, necessitating a method to reduce power consumption while maintaining communication efficiency.
Innovation Solution
A method for Discontinuous Reception (DRX) in unlicensed bands is introduced, where a terminal device switches between non-DRX and DRX modes based on the detection of sidelink and downlink signals. In the DRX mode, the device monitors the channel only during designated periods and enters a sleep state otherwise, reducing unnecessary power usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal device continuously monitors the channel to avoid data loss, then the communication reliability is improved, but the power consumption increases
Solution Approach 1:
The patent implements discontinuous reception (DRX) where the terminal device alternates between active monitoring periods and sleep periods. During active periods, the device monitors grant-free resources for sidelink and downlink signals. When no signals are detected for a predetermined number of consecutive resources, the device enters sleep mode to conserve power, then periodically wakes to check for new signals. This periodic action resolves the contradiction by maintaining reliability during active periods while reducing power consumption during sleep periods.
Solution Approach 2:
The terminal device autonomously determines when to switch between active and sleep states based on its own signal detection results. The device monitors for a predetermined number of consecutive grant-free resources and independently decides to enter DRX mode when no signals are detected, without requiring external control. This self-service mechanism allows the device to balance reliability and power consumption autonomously.
2Duration of action of moving object
If the terminal device enters sleep mode to reduce power consumption, then the battery life is extended, but the response time to detect incoming signals increases
Solution Approach 1:
The terminal device performs preliminary monitoring of a predetermined number of consecutive grant-free resources before entering sleep mode. This preliminary action ensures that the device has thoroughly checked for incoming signals before transitioning to low-power state, minimizing the risk of missing critical communications and reducing the effective delay when waking from sleep mode.
Solution Approach 2:
The device implements periodic wake-up cycles where it alternates between active monitoring and sleep states. During active periods, it monitors for signals; when no signals are detected for a predetermined number of consecutive resources, it enters sleep mode. This periodic pattern balances battery life extension with timely signal detection by ensuring the device is awake and monitoring at regular intervals.
3Productivity
If the terminal device monitors all grant-free resources in non-DRX mode, then the communication efficiency is maintained, but the power consumption is high
Solution Approach 1:
The patent applies periodic action by implementing DRX mode where the terminal device monitors grant-free resources only during active periods and enters sleep mode during inactive periods. The device monitors for a predetermined number of consecutive grant-free resources, and when no sidelink or downlink signals are detected, it transitions to sleep mode. This periodic monitoring pattern maintains communication efficiency during active periods while significantly reducing power consumption during sleep periods, resolving the contradiction between productivity and energy use.
Solution Approach 2:
The device performs partial monitoring by checking only a predetermined number of consecutive grant-free resources before deciding to enter sleep mode, rather than continuously monitoring all resources. This partial action is sufficient to detect incoming signals while avoiding the excessive power consumption of continuous monitoring, thus balancing communication efficiency with power savings.
Data Source
AI summary
This application provides a terminal apparatus and method for discontinuous reception (DRX) in an unlicensed band, and may be applied to a scenario in which a terminal device performs communication through a sidelink or a Uu link. A signal receive end monitors a sidelink signal and/or a downlink signal on a grant-free resource configured by a network device, and switches between a non-DRX mode and a DRX mode when a corresponding preset condition is met. Alternatively, a transmit end directly indicates a receive end to use a DRX mode or a non-DRX mode, or indirectly indicates, with assistance of a network device, a receive end to use a DRX mode or a non-DRX mode. In this way, DRX of the receive end can be implemented in a sidelink unlicensed band or a Uu link unlicensed band. This reduces power consumption of the receive end.