RAN1 #126-bis preview: what the meeting will debate
12 October to 16 October 2026South Korea3GPP TSG RAN WG1Last updated 2026-10-11
At a glance
The meeting is working across synchronization, CSI acquisition, random access, and integration of sensing with communication. Synchronization proposals expose tradeoffs between longer broadcast intervals, acquisition latency, and UE search complexity. Other contributions address CSI configuration, sensing evaluation, and random access coverage. Prior working assumptions set study boundaries, while several technical choices remain proposals.
1Hottest topics
Aspects of integration with communication
Significance 58 of 100, 57 TDocs
A prior working assumption selects sensing-assisted beam management as a representative use case for study. It leaves sensing-assisted CSI acquisition and reporting bracketed. One proposal calls for measuring reference-signal and feedback savings against CSI accuracy and communication-performance loss. Another proposes identifying ambiguous path pairs at the access node or core network.
Continue study of sensing-assisted CSI acquisition and reporting as a representative SAC candidate, including sensing-information representation, association, configuration/update triggering, and fallback; ...
One proposal calls for mandatory mitigations if default SSB periodicity exceeds 20 ms. A separate contribution warns that long periodicity may delay acquisition of information not continuously broadcast. Repetition is also contested: one proposal supports adjustable transmitted SSB repetitions, while another warns about UE combining complexity. These choices affect what a UE must search for during initial acquisition.
One proposal studies dynamic updates to CSI report parameters or downloadable codebooks, bases, and projection matrices. Another proposes studying constellation order with PAPR constraint strength for DFT-s-OFDM-based JSCM. That study would consider PAPR and SGCS together for one-sided and two-sided models. The contributions address different parts of CSI acquisition and do not establish a common design.
For DFT-s-OFDM-based JSCM, jointly study the constellation order and PAPR-constraint strength for one-sided and two-sided models, with PAPR and SGCS jointly considered.
A proposal studies repetitions across Msg1 through Msg4 as a unified coverage method. Another proposes studying random access in SBFD symbols for native support. The first focuses on coverage across the message sequence. The second concerns where random access can operate within an SBFD design.
For 6GR, random access procedure in SBFD symbols should be studied to be natively supported to establish an integrated random access mechanism to maximize uplink ...
A prior FFS says the same MDP definition as the 5GA ISAC study should also be evaluated. One proposal supports UE-based bistatic and cooperative sensing for the lowest-tier UE under bandwidth candidates being discussed. It uses gNB-only monostatic sensing as a reference architecture. A separate proposal calls for studying micro-doppler in sensing channel modeling.
Support the UE-based bistatic sensing and the cooperative sensing as feasible ISAC architectures for the lowest-tier UE under the maximum channel bandwidth candidates under discussion ...
Allowing NW to arbitrarily adjust the actual number of transmitted SSB repetitions without prior knowledge at UE during initial cell search either degrades combining performance ...
The following representative use cases for sensing assisted communication is/are selected for study in Rel-20 ISAC Sensing assisted beam management [Sensing assisted CSI acquisition and ...
Source:R1-2606766 (Chair notes). 3GPP TSG RAN WG1 #126.
Still open (FFS)
Also recorded in:R1-2606766 (Chair notes). 3GPP TSG RAN WG1 #126.
4What to watch
Watch whether the bracketed sensing-assisted CSI use case remains within the working assumption for study.
Source:R1-2606766 (Chair notes). 3GPP TSG RAN WG1 #126.
Watch how proposals address UE knowledge of transmitted SSB repetitions during initial cell search.
Watch whether evaluation of the 5GA ISAC MDP definition advances beyond FFS.
Source:R1-2606766 (Chair notes). 3GPP TSG RAN WG1 #126.
5Busiest agenda items
Agenda item
Title
TDocs
10.5.3.1
Aspects of downlink-based CSI acquisition
63
10.5.2.3
Uplink transmission scheme(s) for uplink channels
57
10.8.2
Aspects of integration with communication
57
10.5.2.2
Downlink transmission scheme(s) for downlink shared channels
56
10.5.1.1
Synchronization acquisition and beam measurement
54
10.5.1.2
PRACH and RACH procedure
50
10.5.2.1
Downlink transmission scheme(s) for downlink control channels
49
10.7.1
NTN specific requirements and design
49
10.5.4.1
Downlink control channel, scheduling for downlink and uplink transmission
48
10.5.3.4
Beam management for downlink and uplink
47
10.8.3
Waveform and frame structure
47
9.4.1
NR-NTN GNSS resilience
46
Built by 3GPP Scout from the public meeting record (1700 TDocs registered, catalog synced 2026-10-11). Significance scores rank topics by decisions, contention, breadth and volume. Excerpts are at most 25 words and link to the original on the 3GPP file server.