T hacks: add new tracer ant0 and a tool to plot ofdm data from usrp or rfsim
(output or input)
The tool ant0 dumps IQ data to a file (or stdout) as float complex or short.
It is needed for a student's project. (Well, we could use record/extract, but
it's simpler.) The tool ofdm-plot is used to plot output or input signal from
gnb in the frequency domain. May be useful to debug, why not.
bridge->nb_cnx++ is done before calling snprintf(modelname,... in the function,
so we take the model name of the next channel. This commit corrects the issue by
using bridge->nb_cnx - 1, ensuring that the model name corresponds to the currently
connected client.
This bug was introduced by MR !3455.
Co-authored-by: Bartosz Podrygajlo <bartosz.podrygajlo@openairinterface.org>
Co-authored-by: Laurent THOMAS <laurent.thomas@open-cells.com>
Fix concurrency issues happening when a new client connects, sometimes
leading to a total softmodem deadlock.
Key changes:
- Fix sample sending on new client connection: send the first
sample only to the newly connected client.
- Remove the --rfsimulator.hanging-workaround option
- Replace global nb_ue and Sockmutex with nb_cnx and Sockmutex
in rfsimulator_state_t for better concurrency and clarity.
Replace the FD <-> buffer_t hashtable with epoll_event_t mapping.
This simplifies the code, reduces the probability of memory leaks and removes a
possible data race on the hashtable during rfsimulator shutdown.
Use `rfsimu_channel_ue1`, `rfsimu_channel_ue2`, etc. if you want to
use different channel models for each client. The client connection
order determines its channel model name.
Enable/disable workaround based on a new option "hanging-workaround".
This addresses an issue where the workaround will trigger even if there
is no risk of a permanent lockup of the system.
Added new command line option to channelmod: noise_power_dBFS. This options
allows the user to configure noise power in dBFS added instead of the per-channel
value.
This makes it so noise is not accumulated per channel reaching higher than expected
values.
The dBFS unit allows easy configuration. The gNB by default uses -36 dBFS setting.
To reach 3dB SNR one should set the noise_power_dBFS value to -39.
To configure using command line use --channelmod.noise_power_dBFS -50. Using this
setting the gNB and nrUE connect without issue.
This commit refactors startServer to use getaddrinfo() to
prepare the socket creation. Doing so, it also adds support for
IPv6 by using AF_UNSPEC as the address family.
This commits uses getaddrinfo(3) when connecting as client to the
rfsimulator. This enables name lookups, through DNS or a hosts file.
This change makes it easier to use the simulator in a dynamic
environment like Docker or Kubernetes by only targeting the name of
the container or service.
It is very possible that the operating system returns a file
descriptor bigger than the size of bridge->buf (MAX_FD_RFSIMU, which
is 250 as of now). As a minimum, let's fail if the socket file
descriptor is out of bounds.
A proper solution may be implemented later, if needed.
The actual propagation delay should not be smaller than the one specified.
A too short propagation delay might result in too early reception of Msg1, and with that in a mis-detection of the RAPID.
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).
Reset all the circular buffer to zero; this ensures that we cannot read
uninitialized data. Since this is RFsimulator, performance is not a
problem here either (and zeroing out happens only once).
Use the correct function in order to close open RFsim connections,
instead of a simple close(). If this is not done correctly, it might
happen that the softmodem closes, but an L1 thread might still read
samples (bug in higher layers). Then, RFsim tries to read a socket
(because it has an open connection), but the actual connection had been
close()d. This commit fixes this behavior.
- deleted: ../../../executables/rfsim.c
- removed unused command line options to set SINR and SNR
- removed unused functions to get SINR and SNR
- removed unused RFSIM struct members
We set the RFsim TCP socket to non-blocking. Thus, it may happen that we
cannot write() to the socket when the kernel cannot handle the request,
in which case we wait some time before trying again. This is the
correct/expected behavior.
Since this is *normal*, an error message is not justified; we did not
even print a message in this case before commit 21790f9c4f introduced it.
This improves the RFsimulator code to reach a ~40% E2E throughput
improvement (depending on the machines).
Changes:
- reduce ring buffer size
- code cleanup for readability
- set TCP kernel parameters
Laurent THOMAS