NR UE: introduce orbit propagation to improve N_UE_TA_adj accuracy

Instead of trying to estimate N_UE_TA_adj with a second degree polynomial,
we introduce orbit propagation to calculate N_UE_TA_adj with higher accuracy.

When we receive the satellite ephemeris data consisting of the satellite position vector
and the satellite velocity vector, we calculate parameters for orbit propagation, assuming
a circular orbit in the plane created by the satellite position vector and the satellite
velocity vector. This is done in the function prepare_ue_sat_ta().

Every millisecond, we use these parameters together with the time since epoch to calculate
the satellite position on that orbit and from this the reound-trip-time between UE and the
satellite, what corresponds to N_UE_TA_adj. This is done in the function apply_ntn_timing_advance().

This commit is contained in:

Thomas Schlichter

2025-11-19 10:05:45 +01:00

committed by

francescomani

parent 43722e6bac

commit 59af5e4ad2

8 changed files with 121 additions and 93 deletions

									
										executables/position_interface.c
									
		+1
		
												View File
												
				@@ -20,6 +20,7 @@

				 */

				#include "position_interface.h"

				#include "executables/nr-uesoftmodem.h"

				static void read_position_coordinates(char *sectionName, position_t *position)

				{