A test was missing in the PRACH RX function of the FHI 7.2 in order to
know if the frame had a PRACH occasion.
This was leading to continuous warning messages as PRACH RX was
triggered on frames in which PRACH was not expected by the scheduler.
saves about 600MB of memory allocation
Move the definition of PRACH items and the PRACH list to the
defs_nr_commons.h file.
Do not re-write the entire structure in nr_schedule_rx_prach(), as it is
quite large now.
Support beam index in OAI 7.2 Fronthaul Interface
This branch supports beam index in OAI 7.2 Fronthaul Interface.
- For CP DL (PDSCH), nBeamIndex of the corresponding prbMapElm is set
when sending IQ data in oran_fh_if4p5_south_out. nBeamIndex of the
corresponding prbMapElm is set when sending IQ data in
oran_fh_if4p5_south_out.
- For CP UL (PUSCH and PRACH), nBeamIndex of the corresponding prbMapElm
is set in oran_fh_if4p5_south_out.
In addition, it fixes a couple of issues
- XRAN hardcodes nBeamIndex of PRACH to zero. Modify XRAN to support
setting of nBeamIndex of PRACH and update xran F release patch.
- Fix the bug in calculating fh_config->neAxc where num_beams_period is
multiplified twice
Testing methodology: Use Benetel O_RU for testing even though it does
not support beamforming. With successful registration and data transfer,
one could check the pcap on the fronthaul interface to see if CP packets
are with the right beam index.
Results:
1. Verified that CP-packets for SSB, DCI, PDSCH, PRACH, PDSCH, PUSCH,
CSI-RS and SRS are with the right beam index
2. Verified that there is no side-effect on Benetel O_RU. UE could
register properly.
3. Verified 4 SSB with ssb_PositionsInBurst_Bitmap = 85. Could see SSB
and PRACH with 4 different indices.
Handle CP UL packet at xran_fx_tx_send_slot() instead of
xran_fh_rx_read_slot(), as the latter would set this information too
late (on reception on samples, but it needs to be filled in the CP
packet prior to reception).
Initialize ru_info structure with beam information, and set beams on TX
direction. Initialize the number of antennas for both RX/TX in both
cases for completeness.
Doing this before using set_master_clock_rate() on the B200 seems to
invalidate clock settings:
[HW] USRP clock set to 1759836386.000000 sec
[...]
[HW] current pps at 3.286750, starting streaming at 4.286750
In other words, the current time setting was reset. With this change
now, we see
[HW] USRP clock set to 1759929873.000000 sec
[...]
[HW] current pps at 1759929873.000000, starting streaming at 1759929874.000000
This is because changing clock sources (I assume setting the master
clock rate impacts the clock) can result in changing the time. From the
documentation of set_time_next_pps() [1]:
> Note: When changing clock sources, a previously set time will most
> likely be lost. It is recommended to set the time after changing the
> clock source. Otherwise, an unexpected time may line up with future PPS
> edges.
[1] https://files.ettus.com/manual/classuhd_1_1usrp_1_1multi__usrp.html#a75b1c5375549e6a446d686ee7d9b4e14
These libraries have an (indirect) dependency on T, either by using the
logging module (which in turn depends on T), or through other includes.
The easiest is to depend on the logging module, which will fulfil also
the T dependency.
It would equally be feasible to use the utils target (which in turn
depends on log_headers), but this would necessitate to compile, and does
not seem to be necessary.
Introduced a parameter start_up_timing which indicates if PM activation is supported during the start-up
procedure. We initialize this parameter, based on the vendor.
Notification interval is set to 10s.
Definition in o-ran-uplane-conf.yang model:
"Gain correction of RF path linked with array element or array layers.
Common part of overall gain_correction.
gain_correction = common array-carrier gain-correction + eAxC gain correction."
RF emulator and improvements of the timers
RF emulator:
Add an RF library emulating a real device without the need of a real
device. This is thought to enable using phy-test without requiring a
radio device or channel simulation. The library synchronizes on the
real time clock, drops TX and generate noise on RX. Noise generation
can be disabled and the noise level configured.
Timers improvements:
- Fix standard deviation for merged timers
- Add display of ULSCH decoding timers
- Add decoding timer in AAL
Taps client for vrtsim
The MR allows vrtsim to connect to the Raytracing Channel Emulator (CE later).
https://gitlab.eurecom.fr/oai/raytracing-channel-emulator
Additional Ubuntu packages required:
- libnanomsg-dev
- flatbuffers-compiler
- libflatbuffers-dev
Everything was tested on the same host. Follow the steps below to
successfully replicate:
1. Build nr-softmodem dependencies
2. Build nr-softmodem for (gNB, nrUE) with OAI_VRTSIM_TAPS_CLIENTset to ON.
3. Start the core network (Optional) follow this tutorial
4. Start the gNB
sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/gnb.sa.band78.fr1.106PRB.usrpb210.conf --gNBs.[0].min_rxtxtime 6 --device.name vrtsim --vrtsim.role server --vrtsim.timescale 0.5 --vrtsim.taps-socket ipc:///tmp/ru_socket_0
5. Start the nrUE
sudo ./nr-uesoftmodem -C 3619200000 -r 106 --numerology 1 --ssb 516 --band 78 --device.name vrtsim --vrtsim.taps-socket ipc:///tmp/ue_socket_0
6. Start the CE Server, once the UE and gNB are running properly, so the
server can connect to IPC sockets
7. Start CE client; the binaries can be downloaded from a pipeline run
or from this link
8. Move the UE in the CE client to generate a new taps array and
populate the taps in softmodems
Replace the unwieldy unix socket implementation of peer information
exchange with an authorative connection descriptor file that
informs the client of the connection method an number of antennas
on the server.
This allows the server to run without the client and allows the
client to reconnect as long as the server is running, as many times
as needed.
Move the channel state management outside the channel implementation.
This simplifies the channel implementation but forces users of the
channel to manage it's state manually.
Add handling for error states in vrtsim which allows to close the
softmodems with CTRL+C without hanging, improving user experience
- Client detection of stale timer.
- Abort state for client and server
Added a libary that can connect to a channel emulator and provide taps
as they are generated.
- Enable connection from vrtsim to channel emulation server
- Depends on flatbuffers definition file from raytracing-channel-emulator
- Depends on libanomsg-dev and flatbuffers-compiler (Ubuntu) or equivalent
- Added a compile time option ENABLE_TAPS_CLIENT to prevent other users
from being affected by additional dependencies
2 functions with same name as static to make it clearer they are separate.
remove unused copy of log_level global var.
remove threequarter sampling variable from the radio board general
configuration. The decision of sampling rate is made above. A better
behavior can be done later, like ask to the radio board what sampling
rate it can do,then use it to decide the appropiate sampling rate from
the gNB configuration. In UE case, it is another issue, as the sampling
rate would change after we decode SIB1, but also it is not developped
yet.
- Allow client to exit cleanly if server is down
- Ensure timing_thread is joined only once avoiding exit_function loop
- Free noise_device
- Save previously sent samples for channel modelling
Add a simple RF emulator library with no real RF.
It only synchronizes the gNB with the real time clock.
It is to be used for stress test or benchmarking in phy-test mode.
LDPC BBDEV/AAL rework
This branch aims to generalize the existing LDPC T2 implementation to support
other DPDK BBDEV accelerators, e.g., Intel ACC100/200.
Differences from the current T2 implementation include:
1. relax CMakeLists.txt checking for custom dpdk-t2 implementation,
technically, any DPDK BBDEV should work
2. BBDEV capability checks during init
3. llr_scaling to scale the input llr accordingly for better decoding
performance on the Intel ACC100/200
4. self-managed harq buffers for the ACC200, as internal harq memory is not
available
Tested BBDEV devices:
1. Intel ACC100
2. Intel ACC200/VRB1
Romain Beurdouche