L1 RX: use queues instead of arrays and linear search for PUCCH, PUSCH, SRS, PRACH
This MR is an attempt to reduce the time L1 RX searches in array for the
next job to process, and instead use a queue. This queue is a FIFO,
because the various jobs (FAPI messages) to process come in order, and
need to be processed in order. The MR (hopefully, to be measured)
reduces the amount of time spent searching for the next UE (because the
next job is always at the beginning of the queue), and should scale
better for many UEs.
It does the following:
- introduce two helper libraries for (1) Frame.Slot calculation (sfn_t),
already introduced in !3521 (merged) commit 3102068e, and (2) a ring
buffer with fixed size
- use sfn_t and ring buffer (gNB->pucch_queue) to remove the linear
array for PUCCH (gNB->pucch)
- use sfn_t and ring buffer (gNB->pusch_queue) for some PUSCH lookups.
Because we need to still store PUSCH contexts, gNB->pusch is still
there
- use sfn_t and ring buffer (gNB->srs_queue) to remove the linear array
for SRS (gNB->srs)
- use sfn_t and ring buffers (gNB->prach_ru_queue and
gNB->prach_l1rx_queue) to remove the linear array for PRACH
(gNB->prach_list)
- some minor cleanups, e.g., additional loops over the PUSCH array,
using const, using pointers instead of indices, etc
OpenAirInterface License
The source code is distributed under CSSL v1.0. Some files, such as for orchestration, are distributed under MIT license(MIT.txt). Documentation is distributed under Creative Commons Attribution 4.0 International license.
All the files without an explicit copyright header have an implicit "Copyright of OpenAirInterface Authors".
Please see NOTICE for other licenses which are used in the software.
In the past OAI source code has been re-licensed sometimes, here is the history:
- CSSL v1.0 starting tag 2026.w14
- OAI Public License v1.1 starting tag v1.0 till
af4b0d53 - OAI Public License v1.0: starting tag v.04 till v1.0
- GPL 3: starting tag v.0 till v.04 (only initial implementation of 4G)
Where to Start
- General overview of documentation
- The implemented features
- System Requirements for Using OAI Stack
- How to build
- How to run the modems
Not all information is available in a central place, and information for specific sub-systems might be available in the corresponding sub-directories. To find all READMEs, this command might be handy:
find . -iname "readme*"
RAN repository structure
The OpenAirInterface (OAI) software is composed of the following parts:
openairinterface5g
├── charts
├── ci-scripts : Meta-scripts used by the OSA CI process. Contains also configuration files used day-to-day by CI.
├── CMakeLists.txt : Top-level CMakeLists.txt for building
├── cmake_targets : Build utilities to compile (simulation, emulation and real-time platforms), and generated build files.
├── common : Some common OAI utilities, some other tools can be found at openair2/UTILS.
├── doc : Documentation
├── docker : Dockerfiles to build for Ubuntu and RHEL
├── executables : Top-level executable source files (gNB, eNB, ...)
├── maketags : Script to generate emacs tags.
├── nfapi : (n)FAPI code for MAC-PHY interface
├── openair1 : Layer 1 (3GPP LTE Rel-10/12 PHY, NR Rel-15 PHY)
├── openair2 : Layer 2 (3GPP LTE Rel-10 MAC/RLC/PDCP/RRC/X2AP, LTE Rel-14 M2AP, NR Rel-15+ MAC/RLC/PDCP/SDAP/RRC/X2AP/F1AP/E1AP), E2AP
├── openair3 : Layer 3 (3GPP LTE Rel-10 S1AP/GTP, NR Rel-15 NGAP/GTP)
├── openshift : OpenShift helm charts for some deployment options of OAI
├── radio : Drivers for various radios such as USRP, AW2S, RFsim, 7.2 FHI, ...
├── targets : Some configuration files; only historical relevance, and might be deleted in the future
└── tools : Tools for use by the developers/ci machines: code analysis and formatting
How to get support from the OAI Community
You can ask your question on the mailing lists.
Your email should contain below information:
- A clear subject in your email.
- For all the queries there should be [Query] in the subject of the email and for problems there should be [Problem].
- In case of a problem, add a small description.
- Do not share any photos unless you want to share a diagram.
- OAI gNB/DU/CU/CU-CP/CU-UP configuration file in
.confformat only. - Logs of OAI gNB/DU/CU/CU-CP/CU-UP in
.logor.txtformat only. - In case your question is related to performance, include a small description of the machine (Operating System, Kernel version, CPU, RAM and networking card) and diagram of your testing environment.
- Known/open issues are present on GitLab, so keep checking.
Always remember a structured email will help us understand your issues quickly.
