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Merge remote-tracking branch 'origin/nr_ue_sib19_ta' into integration_2025_w50 (!3638)

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NR UE: calculate TA based on SIB19 information in NTN mode, if autonomous TA is not enabled

To achieve the goal, the hyper frame number (HFN) is introduced at the NR UE
PHY, MAC and RRC layers.

Besides this, we also implemented an orbit propagation to improve the accuracy
of N_UE_TA_adj, and a fix to keep the N_TA from RAR and MAC CE.

Fixes #981
This commit is contained in:
Jaroslava Fiedlerova
2025-12-08 12:04:31 +01:00
parent 91e7030cf8 92107b18fe
commit e44b17668c
30 changed files with 313 additions and 181 deletions
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doc/FEATURE_SET.md
+3 -1
View File
@@ -352,7 +352,9 @@ These modes of operation are supported:
- Formats 0,1,2,3, A1-A3, B1-B3
* NTN
- TA adjustemt based on ntn-Config-r17 information
- Autonomous TA adjustemt between SIB19 receptions based on DL time tracking
- Different TA adjustemt algorithms between SIB19 receptions:
- Autonomous TA adjustemt based on DL time tracking
- Standard compliant epoch time based TA adjustment including orbital propagation
- UL Doppler pre-compensation based on continuous DL FO estimation
* Highly efficient 3GPP compliant LDPC encoder and decoder (BG1 and BG2 are supported)
* Highly efficient 3GPP compliant polar encoder and decoder
doc/RUNMODEM.md
+4 -2
View File
@@ -356,7 +356,9 @@ sudo ./ran_build/build/nr-uesoftmodem -O ../targets/PROJECTS/GENERIC-NR-5GC/CONF
For LEO satellite scenarios, the parameter `--ntn-initial-time-drift` must be provided via command line, as the UE needs this value to compensate for the time drift during initial sync, before SIB19 was received.
This parameter provides the drift rate of the complete DL timing (incl. feeder link and service link) in µs/s.
Also, to perform an autonomous TA update based on the DL drift, the boolean parameter `--autonomous-ta` should be added in case of a LEO satellite scenario.
To perform an autonomous TA update based on the DL drift, the boolean parameter `--autonomous-ta` can be added.
If that parameter is omitted, the TA is continuously computed based on the SIB19 information.
For LEO satellite scenario we assume the LO to be very accurate and the main FO contribution comes from Doppler shift.
Therefore, we use the command line parameter `--cont-fo-comp 2` to continuously compensate the DL Doppler and pre-compensate the UL Doppler.
@@ -367,7 +369,7 @@ For other information on optional NR UE command line options, please refer [here
So an example NR UE command for FDD, 5MHz BW, 15 kHz SCS, transparent LEO satellite 5G NR NTN is this:
```
cd cmake_targets
sudo ./ran_build/build/nr-uesoftmodem -O ../targets/PROJECTS/GENERIC-NR-5GC/CONF/ue.conf --band 254 -C 2488400000 --CO -873500000 -r 25 --numerology 0 --ssb 60 --rfsim --rfsimulator.prop_delay 20 --rfsimulator.options chanmod --time-sync-I 0.1 --ntn-initial-time-drift -46 --autonomous-ta --initial-fo 57340 --cont-fo-comp 2
sudo ./ran_build/build/nr-uesoftmodem -O ../targets/PROJECTS/GENERIC-NR-5GC/CONF/ue.conf --band 254 -C 2488400000 --CO -873500000 -r 25 --numerology 0 --ssb 60 --rfsim --rfsimulator.prop_delay 20 --rfsimulator.options chanmod --time-sync-I 0.1 --ntn-initial-time-drift -46 --initial-fo 57340 --cont-fo-comp 2
```
# Specific OAI modes