On-Demand PRS Request Signaling in Wireless Random Access
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face inefficiencies in transmitting positioning reference signals (PRS) due to the frequent transmission of PRS signals even when there is no need, leading to increased overhead and power consumption, particularly in scenarios with few or no UEs requiring asset tracking.
Innovation Solution
A PRS request procedure is introduced where user devices (UEs) utilize a random access procedure to request PRS transmission by selecting a downlink reference signal and sending a specific identifier, allowing network nodes to send PRS signals only when needed, optimizing transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If PRS signals are transmitted frequently to ensure positioning availability, then positioning service reliability is improved, but network overhead and power consumption increase
Solution Approach 1:
The patent implements on-demand PRS transmission where the network node transmits PRS signals only when a UE sends a positioning request, rather than transmitting periodically regardless of need. This converts continuous periodic transmission into event-driven periodic transmission, reducing energy consumption while maintaining positioning availability when required.
Solution Approach 2:
The UE autonomously determines when positioning is needed and initiates the request by selecting a downlink reference signal and sending a random access preamble with a specific identifier. The network node then provides the PRS signal only in response to this self-initiated request, enabling the system to serve positioning needs without continuous network probing.
2Measurement precision
If PRS signals are transmitted continuously to maintain positioning capability, then positioning accuracy is improved, but resource utilization efficiency deteriorates
Solution Approach 1:
The system transitions from continuous PRS transmission to event-triggered transmission. The network node monitors for positioning requests and transmits PRS signals only at these discrete moments, improving resource utilization efficiency while maintaining positioning accuracy when actually needed by UEs.
Solution Approach 2:
The PRS transmission schedule becomes dynamic rather than static. The network node adapts its transmission behavior based on real-time UE requests, transmitting PRS signals with variable timing and frequency depending on actual positioning needs, thereby optimizing resource utilization while preserving positioning capability.
3Productivity
If on-demand PRS transmission is implemented to reduce overhead, then resource efficiency is improved, but system complexity increases due to random access procedure modifications
Solution Approach 1:
The patent reuses the existing random access procedure infrastructure for dual purposes: normal connection establishment and positioning request transmission. By making the random access preamble multi-functional (serving both access and positioning request functions), the system avoids creating a separate signaling mechanism, thereby limiting the increase in system complexity while achieving on-demand PRS transmission.
Solution Approach 2:
The random access preamble acts as an intermediary signal that carries positioning request information without requiring a separate dedicated signaling channel. This intermediary approach allows the system to convey positioning needs using existing protocol elements, reducing the complexity that would arise from implementing entirely new signaling procedures.
Data Source
AI summary
A method may include determining, by a user device, an identifier to be used in a random access procedure to indicate a request for a positioning reference signal; selecting, by the user device, a downlink reference signal among a plurality of downlink reference signals received from a network node; controlling sending, by the user device to the network node, as part of a random access procedure, a random access preamble via a random access resource associated with the selected downlink reference signal, and the determined identifier; controlling receiving, by the user device from the network node, the requested positioning reference signal; and carrying out a positioning procedure using the requested positioning reference signal.