Sidelink Positioning Reference Signal Synchronization

The patent introduces a synchronization reference selection mechanism where a target node evaluates multiple candidate anchor nodes based on synchronization quality metrics (such as synchronization signal quality, timing accuracy, and signal strength). The target node selects the best synchronized anchor node as the reference, and other anchor nodes coordinate their SL PRS transmission timing relative to this reference, thereby achieving network-wide synchronization without requiring complex pre-coordination among all anchor nodes

The patent dynamically adjusts synchronization parameters including timing offsets, frequency corrections, and phase alignments based on measured synchronization quality indicators. Anchor nodes modify their transmission timing parameters to align with the selected synchronization reference, ensuring that SL PRS from multiple anchor nodes arrive at the target node with minimized timing differences, thus improving positioning accuracy

The patent establishes a common synchronization reference level across all anchor nodes by selecting a master reference source (or a virtual reference formed by combining multiple sources). All anchor nodes adjust their transmission timing to maintain equal potential (synchronization state) relative to this common reference, ensuring that SL PRS signals from different anchor nodes are equipotential in terms of timing and phase, thereby enabling accurate TDOA measurements

The patent implements a feedback mechanism where the target node measures the arrival timing of SL PRS from multiple anchor nodes and reports timing difference measurements back to the network. Based on this feedback, the network adjusts the transmission timing of anchor nodes to minimize timing differences, creating a closed-loop synchronization system that continuously optimizes positioning accuracy while maintaining simultaneous transmission capability