Configurable coordinate system for angle reporting for positioning
Disclosed are techniques for wireless communication. In an aspect, a base station performs one or more angle-based measurements in a first coordinate system, determines whether to report, to a positioning entity, the one or more angle-based measurements in a local coordinate system (LCS) or a global coordinate system (GCS), and reports the one or more angle-based measurements to the positioning entity in the LCS or the GCS based on the determination. In an aspect, a positioning entity receives, from a base station, one or more angle-based measurements in an LCS of the base station or a GCS, determines whether the one or more angle-based measurements are in the LCS or the GCS, and processes the one or more angle-based measurements based on the determination.
1. A method of wireless communication performed by a base station, comprising:
performing one or more angle-based measurements in a first coordinate system, wherein the one or more angle-based measurements are one or more uplink angle-of-arrival (AoA) measurements;
determining whether to report, to a positioning entity, the one or more angle-based measurements in a local coordinate system (LCS) or a global coordinate system (GCS); and
reporting the one or more angle-based measurements to the positioning entity in the LCS or the GCS based on the determination.
2. The method of claim 1 , wherein the one or more AoA measurements comprise one or more uplink azimuth AoA measurements, one or more uplink zenith angle of arrival (ZoA) measurements, or any combination thereof.
3. The method of claim 1 , wherein:
the one or more angle-based measurements are of one or more uplink reference signals received at the base station from a user equipment (UE), and
the one or more angle-based measurements represent a direction from the base station to the UE.
4. The method of claim 3 , further comprising:
receiving, from the positioning entity, an estimate of a location of the UE based on the one or more angle-based measurements and a distance between the base station and the UE; and
transmitting, to the UE, the estimate of the location of the UE.
5. The method of claim 4 , wherein the distance between the base station and the UE is estimated based on a round-trip-time procedure or a timing advance associated with the UE.
6. The method of claim 1 , wherein the determining comprises determining to report the one or more angle-based measurements in the LCS.
7. The method of claim 6 , further comprising:
reporting, to the positioning entity, assistance data related to the one or more angle-based measurements.
8. The method of claim 7 , wherein the assistance data comprises an indication of which of the one or more angle-based measurements were taken while an orientation of the base station was unchanged.
9. The method of claim 7 , wherein the assistance data comprises a timestamp associated with each of the one or more angle-based measurements and a time at which an orientation of the base station changed.
10. The method of claim 7 , wherein the assistance data comprises an indication that an orientation of the base station changed while the base station was performing the one or more angle-based measurements.
11. The method of claim 7 , wherein the assistance data comprises an indication that an orientation of the base station changed while the base station was performing the one or more angle-based measurements and an amount of the change in the orientation.
12. The method of claim 1 , wherein the determining comprises determining to report the one or more angle-based measurements in the GCS.
13. The method of claim 12 , further comprising:
converting the one or more angle-based measurements from the LCS to the GCS.
14. The method of claim 13 , wherein the converting is based on information related to an orientation of the base station.
15. The method of claim 14 , wherein the orientation of the base station is expressed as a set of bearing, downtilt, and antenna slant angles (a, B, y) in the LCS with respect to the GCS.
16. The method of claim 1 , wherein the base station determines to report the one or more angle-based measurements in the LCS or the GCS based on an ability of the base station to determine an orientation of the base station.
17. The method of claim 16 , wherein, based on the base station being able to determine the orientation of the base station, the base station determines to report the one or more angle-based measurements in the GCS, the method further comprising:
reporting, to the positioning entity, an indication that the one or more angle-based measurements are being reported in the GCS.
18. The method of claim 16 , wherein, based on the base station not being able to determine the orientation of the base station, the base station determines to report the one or more angle-based measurements in the LCS, the method further comprising:
reporting, to the positioning entity, an indication that the one or more angle-based measurements are being reported in the LCS.
19. The method of claim 1 , wherein the determining comprises:
receiving, from the positioning entity, an indication to report the one or more angle-based measurements in the LCS or the GCS.
20. The method of claim 1 , wherein the first coordinate system is the LCS.