Sidelink UE Positioning Using PRS and Assisting Nodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing 5G positioning technologies face challenges in achieving accurate UE positioning in side-link communication, particularly when the UE is not connected to base stations or outside network coverage, due to issues like geometric dilution of precision and limited availability of assisting nodes.
Innovation Solution
A method for positioning a target UE in side-link communication involving establishing communication links between nodes, transmitting capability requests and feedback messages, configuring nodes for PRS transmission and reception, and estimating position based on PRS measurements using methods like SL-TDOA, SL-mRTT, SL-AoA, SL-AoD, and CPP, with assistance from anchor UEs or sidelink positioning servers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional DL-based or UL-based positioning methods are used in 5G network, then positioning can be supported with network infrastructure, but positioning accuracy deteriorates when UE is not connected to base stations or outside network coverage
Solution Approach 1:
The patent introduces sidelink communication as an intermediary mechanism between UEs and the network infrastructure. When traditional network-based positioning is unavailable, UEs can directly communicate with each other via sidelink to perform positioning measurements, serving as a mediator that enables positioning in coverage-free scenarios
Solution Approach 2:
The patent enables UEs to perform self-positioning using sidelink measurements without requiring network infrastructure. The target UE and assisting UEs autonomously exchange positioning reference signals and perform measurements independently, allowing the system to serve itself when network support is absent
2Measurement precision
If multiple assisting nodes are used for positioning, then positioning accuracy improves, but geometric dilution of precision occurs when nodes are poorly distributed
Solution Approach 1:
The patent dynamically selects assisting UEs based on real-time conditions such as signal quality, geometric distribution, and availability. The system adapts the set of assisting nodes rather than using a fixed configuration, optimizing the balance between having enough nodes for accuracy while maintaining good geometric distribution to avoid GDOP
Solution Approach 2:
The patent changes the parameters of the positioning system by allowing flexible selection of which UEs serve as assisting nodes. By varying the composition of the assisting UE set based on geometric distribution quality and signal conditions, the system optimizes positioning reliability while maintaining accuracy
3Reliability
If sidelink positioning is implemented without network coverage, then positioning availability improves, but positioning accuracy deteriorates due to limited assisting nodes
Solution Approach 1:
The patent makes the sidelink positioning system universal by designing it to function in multiple scenarios: both with and without network coverage. The same sidelink positioning mechanism serves dual purposes, providing positioning capability independently of network infrastructure while maintaining compatibility with network-assisted modes when available
Data Source
AI summary
A method of positioning a target node (204-5) in a side-link communication system in a wireless communication network (200) is described. The method comprises establishing a communication link with the target node (204-5), and a second node (204-3), for positioning the target node (204-5). The first node (204-1) transmits a capability request message to the target node (204-5) and the second node (204-3) and receives a feedback message comprising a capability reply message and an acceptance message. The first node (204-1) configures the second node (204-3) for transmitting and receiving a Positioning Reference Signal (PRS) to or from the target node (204-5), based on the feedback message. The PRS is utilized for determining position measurement of the target node (204-5). The first node (204-1) receives data related to the position measurement and estimated position of the target node (204-5), from the target node (204-5) and the second node (204-3).