Fix Delta MCS mode, reimplement UL power control
This change set fixes the "delta-MCS" mode, and reimplements the UL power
control loops at gNB, i.e., for PUSCH and PUCCH. It further adds new T traces
to log PUSCH/PUCCH power infrmation, and cleans up code.
The "delta-MCS" mode in OAI refers to configuring a UE with deltaMCS in the
PUSCH-PowerControl IE (see TS 38.331). In this mode, the UE adjusts the PUSCH
power for transmissions to take into account for MCS (see TS 38.213 Sec. 7.1).
In other words, the target SNR can be set to a somewhat low value, and the UE
will still use the right power for UL transmissions. Note that the spec only
foresees this adjustment of UL power when using one layer. In contrast, in the
"normal" mode, the gNB sends TPC commands to keep a UE at a fixed target SNR
(default: 20dB), regardless of the MCS or number of layers. Future work is
planned to completely remove this fixed target SNR, which is not done in this
MR yet.
Further, there is a new power control loop implementation. Prior to this MR, on
each UL transmissions, the gNB uses the SNR to decide about TPC sent to a UE in
the next transmissions. The new implementation relies on averaging the SNR, and
a "TPC in flight" average to account for the slow reaction of the average SNR.
The sum of both quantities is the current SNR that is used by the UE. See the
commit messages or documentation for more information.
Further cleanup to group data (e.g., power control configuration, refactoring of
code to save space, ...) is done. Two new T traces GNB_MAC_PUSCH_POWER_CONTROL
and GNB_MAC_PUCCH_POWER_CONTROL are added; documentation exists to explain how
to graphically plot corresponding graphs.
PUCCH Format 1 decoder implementation and validation with nr_pucchsim
This is the implementation of the PUCCH Format 1 decoder, validated with
pucchsim in the current branch.
Build:
./build_oai --nrUE --gNB --ninja --phy_simulators
Run tests:
ctest -L nr_pucchsim -j 8
This commit completes the PUCCH Format 1 decoder implementation using
maximum-likelihood detection with RE averaging across symbols/RB (and
hop-wise averaging for intra-slot hopping). It also updates the PUCCH
simulation/test flow to align with the decoder changes, including
payload and logging consistency fixes needed for correct validation.
Use flat buffer for txdataF in gNB L1
This MR changes txdataF buffer format to hold freq domain data starting from
PRB0 instead of circular buffer that starts from PRB N/2. The motive is to
simplify RE mapping function in L1 and copying data to xran lib.
Added NTN-FR2 FDD bands defined in release 18 in Ka-band range
* NTN-FR2 bands 510, 511, 512 added. TS 38.101-5 v 18.9 defines these 3 FR2-FDD
bands for NTN operation.
* These bands are defined in Ka band range (17.3Ghz - 31Ghz).
* Tested using the added conf files using RFSIM and GEO configuration.
* There were some inconsistencies observed when testing with RFSimulator before UE
Syncs to the gNB in terms of samples being written for FR2 configurations. Once
the UE syncs, the inconsistencies disappear.
* this is the problem - UE writes incorrect number of samples and gNB complains
about getting samples in past
* The above inconsistencies were also fixed in this merge request.
* These commits solving above inconsistencies were removed from this MR and a
different MR was raised. MR with those commits: !3928.
So far txdataF buffer has DC RE as the first element. This was prefered
most likely to avoid memcpy before iFFT but comes with a small
complexity in RE mapping functions.
Instead, we use a flat buffer that holds freq domain data starting from
first negative SC. After resource mapping is done on all channels, each
OFDM symbol is shifted before iFFT so that the buffer start with DC RE.
This reduces complexity in mapping functions and later on when passing
beam IDs to 7.2 split RU especially when a beam is associated to
interleaved RB and/or REs.
There is already a memcpy in place to copy txdataF from gNB stuct to RU
struct. So this change does not introduce new memcpy.
Remove unused function arguments
Some of them, because there are hundreds if not thousands. Warnings at compilation time can be enabled using -Wunused-parameter.
Configure CSI-RS according to beam_id used by UE
This MR is to configure CSI-RS according to beam_id used by UE and
reconfigure upon beam change.
It has been tested with RFSIM, Liteon and Microamp under multiple beams.
GPU Channel Simulation: nr_dlsim/nr_ulsim Integration + CI Test
This MR is a follow-up to !3886 (merged) and extends CUDA-based channel
simulation support to nr_dlsim and nr_ulsim, together with the
corresponding CI tests.
The MR incorporates:
- Cherry-picked commits e0c204f7 and 5f344876 from !3588
- Integration of new CI physim tests using GPU-accelerated channel
simulation in nr_dlsim and nr_ulsim tests, see commit c727b3bb
New CI job: RAN-Channel-Simulation
https://jenkins-oai.eurecom.fr/job/RAN-Channel-Simulation/
Fix compilation error:
/oai-ran/openair1/SIMULATION/NR_PHY/dlsim.c:932:42: error: variable 'h_channel_coeffs' set but not used [-Werror,-Wunused-but-set-variable]
932 | float *h_channel_coeffs = NULL;
| ^
- Introduce usage of the -f option in ulsim to allow enabling specific
feature flags at runtime.
- Add support for the "cuda" flag to enable CUDA channel simulation when
compiled with CUDA support. If an unsupported flag is provided, nr_ulsim
reports an error.
This commit integrates the GPU-based channel simulation pipeline into
the ulsim.
A `--cuda` command-line flag is added to enable the GPU path at
runtime. When activated, the simulator will:
- Allocate all necessary GPU and pinned host memory via the
`init_cuda_chsim_buffers` helper function.
- In the main simulation loop, call the `run_channel_pipeline_cuda`
function to perform the channel simulation on the GPU, bypassing the
CPU-based functions.
- Clean up all CUDA resources on exit using the
`free_cuda_chsim_buffers` helper.
The cpu path is also updated to use multipath_channel_float and add_noise_float.
- Replace previous handling of -f with a generic feature flag option.
- Add support for the "cuda" flag to enable CUDA channel simulation when
compiled with ENABLE_CUDA.
- Remove unused SCGroupConfig file handling (scg_fd) and related code.
- Clean up deprecated code and variables associated with SCG reading - not
required anymore after b232be94ed
Remove L1 dependence from NR band number
L1 band information relied on get_band function that couldn't provide an
unambiguous result. Also there is no SCF compliant parameter for L1 and
generally we don't really need that information in L1.
The MR also remove a RU section that used nr_band but was never really
accessed in NR.
Fix error
openair1/SIMULATION/NR_PHY/dlsim.c:1057:37: runtime error: member access within misaligned address 0x7f8a67e01010 for type 'struct NR_Sched_Rsp_t', which requires 32 byte alignment
Prior to this commit, constants NB_ANTENNAS_RX/TX are provided on the
command line to each compiler invocation. This has the drawback (1) that
also files that don't need that get the constants, and (2) it is not
easy to find them using ctags or similar, as the only definition is in
CMakeLists.txt (where it is not found).
In this commit, use cmake configure_file() to write a header file with
these constants. The file will be generated during cmake invocation, and
written to <build-dir>/common/cmake_defs.h. The relevant files that
need this definition will pick it from the header.
This has been used previously also in a commit to write git information.
See-also: 8bffd1666d ("Avoid complete rebuild on cmake run with git info change")
This commit integrates the CUDA-based channel simulation pipeline into
the nr_dlsim.
A new `--cuda` command-line flag is added to enable the GPU path at
runtime. When activated, the simulator will:
- Allocate all necessary GPU and pinned host memory via the new
`init_cuda_chsim_buffers` helper function.
- In the main simulation loop, call the `run_channel_pipeline_cuda`
function to perform the channel simulation on the GPU, bypassing the
CPU-based functions.
- Clean up all CUDA resources on exit using the
`free_cuda_chsim_buffers` helper.
Additionally, dlsim is now using the float version of channel_multipath and add_noise functions.
Also, The input data is formatted as interleaved IQ, with separate antennas to ensure a fair comparison with the GPU operation.
Remove VCD signal dumper from NR code
We don't test VCD in 5G NR code (and haven't tested it in 4G for years).
Remove the VCD traces in 5G code to avoid any ambiguity. 4G code remains
in place, as well as the tools to analyze existing traces.
In this case, there are a number of linker errors:
/usr/bin/ld: libL2_NR.a(rrc_gNB.c.o): in function `nr_rrc_transfer_protected_rrc_message':
/home/richie/oai/openair2/RRC/NR/rrc_gNB.c:330:(.text+0x6f6): undefined reference to `signal_rrc_msg'
However, nr_srssim does not need RRC, while it is being linked in. Thus,
link without nr_rrc and L2. For the remaining two linker problems:
- provide a definition of NR_IF_Module_init() as in most other
simulators
- move rrc_get_max_nr_csrs() to nr_common.c. It is already declared in
the corresponding header, and itself does not have anything to do with
RRC radio configuration, therefore it does not belong to
nr_radio_config.c
For now, test in the following configuration:
- 16 parallel channels
- channel length of 32 and 128
- with 61440 and 122880 samples
- 12 trials per each test (due to CUDA kernel loading delay in first iterations)
- multiple MIMO configurations: 2TX - 2/4/8/32 RX, 2/4/8/32 TX - 2RX
This commit extends the CUDA API with new functions designed for
high-throughput scalability testing and advanced concurrency.
Key additions include:
- Batched versions of the kernels (`..._batched`) that use the
`blockIdx.z` grid dimension to process many independent channel
simulations in parallel.
- A C-callable wrapper, `run_channel_pipeline_cuda_batched`, to
orchestrate the execution of these new kernels.
- A "streamed" version of the pipeline,
`run_channel_pipeline_cuda_streamed`, which accepts a
`cudaStream_t` as an argument. This allows the calling
application to manage the execution stream, enabling overlap
with other GPU or CPU tasks.
This commit introduces the main C-callable pipeline function,
`run_channel_pipeline_cuda`, located in a new `channel_pipeline.cu`
file.
This function serves as the primary entry point for the GPU channel
simulation. It orchestrates the entire sequence of operations:
- Manages Host-to-Device data transfers for the input signal and
channel coefficients.
- Launches the `multipath_channel_kernel` and the
`add_noise_and_phase_noise_kernel` in the correct order.
- Manages the Device-to-Host data transfer for the final output signal.
- Synchronizes to ensure completion before returning.
This commit adds the CUDA implementation for adding Additive White
Gaussian Noise (AWGN) and phase noise to the signal. The code is
located in phase_noise.cu.
- The `add_noise_and_phase_noise_kernel` uses the NVIDIA cuRAND
library for efficient parallel random number generation.
- Helper functions are included to create, initialize, and destroy
the cuRAND states required by the kernel.
- Placeholder for a C-callable wrapper, `add_noise_cuda`, is also
provided.
This commit introduces the CUDA implementation of the multipath channel
model in `multipath_channel.cu`.
- Implements `multipath_channel_kernel` using shared memory for
efficient, high-performance convolution.
- Provides a C-callable wrapper, `multipath_channel_cuda`, to
orchestrate the full pipeline of data transfers and kernel
launches.
- The wrapper includes support for multiple memory models (Explicit
Copy, Unified Memory, ATS) via preprocessor directives to adapt to
different build configurations.
- Adds a `interleave_channel_output_cuda` utility to convert signal
data from the CPU's planar format to the GPU's interleaved format.
This commit refactors the CPU-based channel model for improved reusability and extends it with single-precision floating-point support.
This serves as a performance and correctness baseline for the new CUDA implementation.
Key changes include:
- The original double-based multipath_channel function is refactored to remove hardcoded antenna dimensions from its signature. It now accepts dynamically sized arrays, making it more flexible for use in simulators like dlsim and ulsim.
- A new multipath_channel_float function is introduced to operate on float data types, matching the GPU's native format.
- A corresponding add_noise_float function is also added to complete the floating-point CPU pipeline.
- The new float-based functions are designed to work with an interleaved IQ sample format ([I, Q, I, Q]), which is more suitable for vectorized (SSE) and GPU processing.
Jaroslava Fiedlerova