UE-Assisted TRP Synchronization via Precoded Uplink RS
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face challenges in accurately and efficiently synchronizing transmission and reception points (TRPs) due to potential transmission and reception mismatches, especially in weak or impaired channels.
Innovation Solution
The proposed solution involves user equipment (UE)-assisted time and phase synchronization for coherent joint transmission (CJT), where the UE precodes uplink reference signals based on downlink reference signals received from multiple TRPs, thereby reducing channel phase impacts and enabling accurate offset estimation for TRP synchronization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional synchronization methods are used between TRPs, then the system complexity remains low, but the synchronization accuracy deteriorates in weak or impaired channels
Solution Approach 1:
The patent introduces a UE-assisted measurement mechanism where the UE acts as an intermediary to facilitate synchronization between TRPs. The UE receives downlink reference signals from multiple TRPs, performs precoding based on channel estimates, and transmits uplink reference signals that enable accurate time and phase offset estimation without requiring direct TRP-TRP communication infrastructure
Solution Approach 2:
The patent replaces traditional mechanical or infrastructure-based synchronization methods (such as GPS or wired backhaul synchronization) with a wireless signal-based approach. By using precoded uplink reference signals transmitted through the wireless channel, the system substitutes physical synchronization infrastructure with signal-processing-based synchronization that adapts to channel conditions
2Measurement precision
If UE precodes uplink reference signals based on downlink reference signals, then the phase offset estimation accuracy improves, but the transmission time and processing overhead increase
Solution Approach 1:
The patent applies preliminary action by having the UE perform downlink channel estimation and precoding calculation before transmitting the uplink reference signal. The UE receives downlink reference signals, estimates the channel response, computes the precoding matrix, and prepares the precoded uplink signal in advance, which enables accurate phase offset measurement when the signal is transmitted
Solution Approach 2:
The patent merges multiple functions into the UE's precoding operation: channel estimation, precoding calculation, and reference signal transmission are combined into a single integrated process. This consolidation reduces the number of separate signaling steps and enables the phase offset information to be embedded within the normal uplink reference signal transmission
Data Source
AI summary
Methods, systems, and devices for wireless communication are described that support user equipment (UE)-assisted transmission and reception point (TRP) synchronization. A first TRP and a second TRP may send a first downlink reference signal (RS) and a second downlink RS to an assisting UE. The assisting UE may transmit a first uplink RS to the first TRP and a second uplink RS to the second TRP, where the first uplink RS and the second uplink RS are precoded based on the first downlink RS and the second downlink RS. A central node may calculate a relative timing offset, relative phase offset, or both, between the first TRP and the second TRP based on the first uplink RS and the second uplink RS. Then, one of the first TRP or the second TRP may use the relative timing offset, phase offset, or both to synchronize with the other TRP.