CSI-RS Configuration for Faster, Lower-Power NR Terminal Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In NR terminals in RRC idle or inactive states, the long synchronization period of SSB/PBCH blocks necessitates terminals to wake up and synchronize dozens or hundreds of milliseconds before receiving system or paging messages, which is not energy-efficient.
Innovation Solution
Configuring CSI-RS signals through system information and/or paging messages for time-frequency synchronization, allowing terminals to use additional reference signals like CSI-RS alongside SSB to reduce synchronization time and conserve energy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If terminals use SSB for synchronization before receiving system information or paging messages, then synchronization can be achieved, but the long period of SSB (at least 5 ms, typically 10 ms or 20 ms) requires terminals to wake up dozens or hundreds of milliseconds in advance, increasing power consumption
Solution Approach 1:
The patent segments the synchronization function by introducing multiple types of reference signals (SSB, CSI-RS, PTRS) with different periods and purposes. Instead of relying solely on SSB for all synchronization needs, the system divides synchronization into coarse synchronization (using SSB) and fine synchronization (using CSI-RS with shorter period), allowing terminals to achieve accurate synchronization faster and reduce wake-up time.
Solution Approach 2:
The patent applies preliminary action by configuring CSI-RS resources in advance through system information or paging messages, so that when terminals need to synchronize, the CSI-RS signals are already available and properly configured. This eliminates the need for terminals to wait for SSB periods and perform extensive processing, enabling faster synchronization with reduced power consumption.
2Measurement precision
If terminals wake up dozens or hundreds of milliseconds in advance to synchronize using SSB, then accurate synchronization can be achieved, but this early wake-up increases power consumption and reduces energy efficiency
Solution Approach 1:
The patent introduces dynamic reference signal configurations where CSI-RS resources can be adaptively configured with different periods, offsets, and parameters based on terminal needs and network conditions. This dynamic approach allows the system to optimize synchronization speed and accuracy in real-time, reducing the fixed wake-up time requirement imposed by static SSB periods.
Solution Approach 2:
The patent changes key parameters by introducing CSI-RS with configurable periods (shorter than SSB), different frequency offsets, and adjustable power levels. By changing these parameters, the system enables terminals to achieve the same synchronization accuracy with shorter observation windows and reduced wake-up time, directly addressing the time-loss problem.
3Device complexity
If the system uses only SSB for synchronization, then the implementation is simple, but the long period limits the speed of synchronization and energy efficiency
Solution Approach 1:
The patent makes reference signals universal by designing CSI-RS to serve multiple functions: it can be used for channel estimation, interference measurement, and synchronization. This multi-functionality allows the same signal structure to address both the simplicity requirement (by reusing existing signal formats) and the speed requirement (by enabling faster synchronization through shorter periods and flexible configuration).
Data Source
AI summary
Disclosed are a reference signal configuration method, a network device, and a terminal device. The method includes: the network device sends configuration information of one or more reference signals through system information and/or paging messages to a terminal device in a Radio Resource Control (RRC) idle state or in a RRC inactive state, where the reference signal is a Channel-state information (CSI)-Reference Signal (RS); and the terminal device receives configuration information of one or more reference signals through system information and/or paging messages by the terminal device.