It might be desirable to run the UE without superuser rights. More
concretely, it might run without NET_ADMIN. In this case, various
corresponding operations on the TUN socket fd might fail. In this
commit,
- improve error reports to make them more clear
- do not automatically exit(1), but return from the function to ensure
continuity of the softmodem
A particular GCC version (v13?) used by CI machines potentially has a
bug that issues a mismatch bound warning on function array arguments.
This commit should prevent it from happening.
Till this commit, the UE gets the position of SSB in frequency from
command line and does the syncronization by locating the SSB in time. It
does this by generating a PSS time signal during initialization with the
SSB offset given via command line. Then PSS detection is done by
correlation.
In this commit, the UE computes a list of GSCN in the current NR band
that falls within the current bandwidth for the set center frequency.
For each GSCN in the list, the UE starts a thread and performs the
following:
1. Generate PSS time signal with SSB offset for current GSCN.
2. Detect PSS, SSS and decode PBCH (this step remains the same).
After all threads finishes, the results are collected.
For now, only the first detected PBCH is used to proceed further. So
this PBCH is indicated to MAC and UE exits initial sync.
Future work: The cell search can be standalone feature where the UE
could scan for SSB in the entire NR band. This would require changing
radio's frequency on the fly as the UE's bandwidth would not cover an
entire NR band. The cell detection can futher be imporved by looking
for SIB1 for each decoded PBCH.
Add the option `--rfsimulator.prop_delay` to specify the simulated receive-path (gNB: UL, UE: DL) propagation delay in ms.
This option can be used e.g. to simulate a simple GEO satellite channel by specifying `--rfsimulator.prop_delay 238.74` to both, the gNB and the UE.
This is part of the work developed by Fraunhofer IIS within the ESA-funded project 5G-GOA (https://connectivity.esa.int/projects/5ggoa).
Add ulsch decoding measurements, which are reported by nr_ulsim. Start ulsch_decoding_stats measurement before
nr_ulsch_decoding is called and stop it after collection of all decoder tasks from Tpool. In the context of nr_ulsim,
ULSCH_id is allways == 0, testing is performed per one TB, therefore measurement is started and stopped only once per trial.
Reported ulsch decoding statistics show the mean ulsch decoding time over x trials (specified by -n command line option of nr_ulsim).
This measurement does not provide valid information in case of nr-softmodem, when the loop is done over multiple ULSCH IDs -
start of the measurement is done multiple times and stops only once in this case.
For unitary physical simulators, ULSCH processing loop is executed only once
- the max number of PUSCH is set to 1. This ensures exactly one start and stop
of the ULSCH decoding time measurement per processed TB.
Note: ulsch decoding statistics reports average time of segmentation, rate matching, interleaving and decoding of the TB
Robert Schmidt