[FHI72] Fix the PRACH FFT size
ru_config->fftSize is used for the C-plane Section Type 3 which is
dedicated for PRACH and mixed numerology. Previously, we assumed that
PRACH FFT size is equivalent to PxSCH FFT size, but should be based on
the PRACH format.
Tests with the following RUs:
- [x] Benetel v1.2.2 & v1.4.1
- [x] VVDN Gen 3
- [x] Liteon 02.00.10
- [x] Metanoia v2.2.8 (Jura)
Integration `2025.w51`
* !3816 Add two missing include guards
* !3715 Pass beam ID as per FAPI v222.10
* !3777 UE NTN : Fix in case SIB19 periodicity is greater than 2 secs
* !3813 Reset outdated PUCCHs to avoid Assertion caused by non-processed and active PUCCHs
* !3815 Remove phy_extern_nr_ue file
* !3824 CI: adjust UE attach timeout handling
* !3735 vrtsim: Optimize channel modelling
See merge request oai/openairinterface5g!3817
Per TS 33.501 6.9.2.3.4 and Fig 6.9.2.1.1-1, when sending
RRCReestablishment with nextHopChainingCount, the gNB is staying at
the same NCC level (not advancing). Therefore, horizontal derivation
from the currently active KgNB must be used, not vertical derivation
from NH.
Vertical derivation (from NH) is only used when advancing to a new
NCC level, which happens during handover or masterKeyUpdate procedures.
The previous implementation incorrectly used vertical derivation from
NH whenever nh_ncc > 0, which caused key mismatch between gNB and UE
during reestablishment after handover, leading to integrity check
failures.
This fix ensures both gNB and UE use horizontal derivation when
nextHopChainingCount matches the current NCC level, aligning with the
specification's "virtual NH at NCC=0" model where:
- Horizontal derivation = derive KNG-RAN* from currently active KgNB
- Vertical derivation = derive KNG-RAN* from NH (only when advancing NCC)
Refactor key derivation logic to properly handle Next Hop (NH) chain
synchronization according to 3GPP TS 33.501 specifications for both
RRC Reestablishment and Master Key Update procedures.
Changes in rrc_gNB.c:
- Clarify key derivation in rrc_gNB_generate_RRCReestablishment by
explicitly selecting base key (NH or KgNB) based on nh_ncc value
- Add comment explaining vertical vs horizontal derivation logic
Changes in rrc_UE.c:
- Add nr_sync_nh_chain(): Common helper to synchronize NH parameter
chain per TS 33.501 Annex A.10, supporting both Master Key Update
and RRC Reestablishment procedures
- Add nr_derive_kgnb_horizontal(): Derive KNG-RAN* from current KgNB
when NCC values match (horizontal derivation per TS 33.501 A.11/A.12)
- Add nr_derive_kgnb_vertical(): Derive KNG-RAN* from synchronized NH
after NH chain sync (vertical derivation per TS 33.501 A.11/A.12)
- Add nr_update_kgnb_from_ncc(): Unified function implementing TS 33.501
6.9.2.3.4 logic for updating KgNB based on received nextHopChainingCount
- Refactor as_security_key_update(): Use new nr_update_kgnb_from_ncc()
helper function for cleaner, more maintainable code
- Fix nr_rrc_ue_process_rrcReestablishment(): Properly handle received
nextHopChainingCount and update KgNB using unified helper function
- Add debug logging for key derivation process
Key NAS deriver utils:
- update derive_kgnb documentation and protect input keys with const attribute
Make sure to apply Doppler and TA not directly when receiving the target cell ntn_config,
but apply Doppler just before the initial sync, and the TA after the initial sync when
we have tha actuel cell frame and slot numbers.
We need the ntn_config when reconfiguring the PHY layer for a new initial sync,
e.g. for calculating the DL Doppler frequency.
As a dedicated scheduled_response dl_config PDU it reaches the PHY layer too late,
as part of the phy_config.config_req it reaches the PHY layer in time with the
other configuration values.
vrtsim: Optimize channel modelling
Optimization pass for channel modelling on transmission in vrtsim. This
comes from a requirement of O-RU to perform channel modelling with minimum
latency. The latency measured in O-RU 4TX 2RX on the UE is lowered from
~400 uS to ~100uS.
- Reduced MAX_CHANNEL_LENGTH to 200 and introduced SAVED_SAMPLES_LEN
- Refactored channel modelling actor allocation to parallelize work better
- Improved batching and task creation for channel modelling
- Replaced static global saved_samples with local static buffer in vrtsim_write_with_chanmod
Create a new CI pipeline for testing with vrtsim on Gracehopper:
https://jenkins-oai.eurecom.fr/job/RAN-VRT-Sim-Test-5G/
CI: adjust UE attach timeout handling
This modification addresses an issue in the RFSim-5G 2x2 test where the UE
often fails to attach within the initial 20s window. The timeout may cause
the UE to restart, which leads to two UEs appearing in the gNB log. By
increasing the initial timeout to 40s, we avoid unnecessary restarts.
- Set default attach_timeout to 40s
- Increase timeout only after failed attach attempts
This modification addresses an issue in the RFSim-5G 2x2 test where the UE
often fails to attach within the initial 20s window. The timeout may cause
the UE to restart, which leads to two UEs appearing in the gNB log. By
increasing the initial timeout to 40s, we avoid unnecessary restarts.
This function is to be called by the application to switch beams
on reception and transmission. When receiving new samples using
trx_read/trx_write the application is expected to be able to
determine which beam the samples belong to.
Reset outdated PUCCHs to avoid Assertion caused by non-processed and
active PUCCHs
When there is real-time issues in L1 it may happen that the scheduler
misses/skips some slots, thus, L2 not processing and not freeing some
structures like PUCCH. This commit avoids the Assertion by resetting
any Active outdated PUCCH
UE NTN : Fix in case SIB19 periodicity is greater than 2 secs
This was observed when testing OAI NTN UE against a third party gNB (UXM).
LEO SIB19 periodicity of > 2000 ms was used, in which case T430 timer expires
before SIB19 is re-read. This fix handles the case where SIB19 periodicity >
2secs, such that SIB19 is re-read in time and T430 timer does not expire.
Pass beam ID as per FAPI v222.10
This MR
1. Sets MSB of beam ID when passing beam ID to 7.2 radio
2. Modifies phytest scheduler to allocate SSBs on different beams
3. Introduce new MAC config parameter for beam mode to specify HiPHY or LoPHY
beamforming
In perfrom_channel_modelling, do convolution in batches which allows
vrtsim to write the channel samples as they are being produced instead
of waiting for the last sample in the slot to be ready.
Limit sample history to 256 samples and copy it into each channel modelling
task instead of relying on globally available buffer. This simplifies the code
and addressing into the saved samples buffer as well as enabling further
optimizations without sacrificing thread safety.
We assumed that PRACH FFT size is equivalent to PxSCH FFT size.
However, the parameter ru_config->fftSize is used for the C-plane Section Type 3
which is dedicated for PRACH and mixed numerology.
Based on the PRACH format, short or long, the PRACH values 256 or 1024
shall be filled.
Co-authored-by: knopp <raymond.knopp@eurecom.fr>
When doing analogue beamforming, the beam ID for a pre-defined beam
table is passed directly to RU and there is no need to store the beam
table in PHY.
francescomani