The present document captures the findings of the study item "Study on Expanded and Improved NR Positioning" [7]. The purpose of this technical report is to document the requirements, additional scenarios, evaluations, and technical proposals treated during the study and provide a way forward toward normative work on expanded enhancements to NR positioning in TSG RAN WGs.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

• References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.

In Release 17, 3GPP RAN conducted studies on "NR positioning enhancements" TR 38.857 and "Scenarios and requirements of in-coverage, partial coverage, and out-of-coverage NR positioning use cases" TR 38.845. The study on "Scenarios and requirements of in-coverage, partial coverage, and out-of-coverage NR positioning use cases" focussed on V2X and public safety use cases with the outcome being captured in TR 38.845. Additionally, SA1 has developed requirements in TS 22.261 for "Ranging based services" TR 22.855 and has developed positioning accuracy requirements in TS 22.104 for IIoT use cases in out-of-coverage scenarios. There is a need for 3GPP to study and develop sidelink positioning solutions that can support the use cases, scenarios and requirements identified during these activities. The study on "NR positioning enhancements" TR 38.857 investigated higher accuracy, and lower latency location, high integrity and reliability requirements resulting from new applications and industry verticals for 5G. Some of the enhancements identified during that work have been specified during the Release 17 Work Item on "NR positioning enhancements", but there remain a number of opportunities for enhancement that have not yet been incorporated into the specifications. Regarding higher accuracy, two promising techniques identified in earlier studies will be considered in Release 18: one is to take the advantage of the rich 5G spectrum to increase the bandwidth for the transmission and reception of the positioning reference signals based on PRS/SRS bandwidth aggregation for intra-band carriers, and the other is to use the NR carrier phase measurements. GNSS carrier phase positioning has been used very successfully for centimetre-level positioning but is limited to outdoor applications. NR carrier phase positioning has the potential for significant performance improvements for indoor and outdoor deployments in comparison with the existing NR positioning methods, as well as shorter latency and lower UE power consumption in comparison with RTK-GNSS outdoors. Positioning integrity is a measure of the trust in the accuracy of the position-related data and the ability to provide timely warnings based on assistance data provided by the network. The focus in Release 17 work was on GNSS integrity, and for Release 18 it is natural to extend this to address other positioning techniques as well as there are relevant integrity aspects of mission critical use cases that rely on positioning estimates and the corresponding uncertainty estimate. Integrity enables applications to make the correct decisions based on the reported position, e.g., when monitoring a robotic arm to decide whether its arm movement are within allowed limits to ensure safety distances to humans and other objects. SA1 has introduced requirements for LPHAP (Low Power High Accuracy Positioning) for industrial IoT scenarios including use cases such as massive asset tracking, AGV tracking in industrial factory and person localization in danger zones. The SA1 requirements are for high accuracy and extreme low power consumption with battery life sustainable up to one or more years. A typical scenario of interest is use case 6 as defined TS 22.104, which corresponds to tracking of workpiece (in- and outdoor) in assembly area and warehouse with a target accuracy of <1m, a positioning interval of 15-30 seconds, and a battery life of 6-12 months. While Release 17 NR positioning has introduced support for positioning in RRC_INACTIVE state, there is a need to evaluate whether the current system allows LPHAP requirements to be met. Release 17 has specified support for RedCap UEs with reduced bandwidth support and reduced complexity including reduced number of receive chains. Such UEs could support NR positioning functionality but there is a gap in that the core and performance requirements have not been specified for the positioning related measurements performed by RedCap UEs, and no evaluation was performed to see how the reduced capabilities of RedCap UEs might impact eventual position accuracy. This gap is to be investigated by the present SI.