R1-2508731
discussion
Energy Saving for 6GR air interface
From OPPO
Summary
This OPPO contribution (R1-2508731) for the 6G Study Item on Energy Efficiency provides 25 Proposals and 14 Observations covering power models, evaluation metrics, and energy-saving techniques for both network and UE sides. It proposes specific reference configurations, power model enhancements including new UE sleep states and SCMC scaling, and evaluates techniques like increased SSB periodicity, OD-SSB/SIB1, cell DTX/DRX, and two-stage PDCCH design, quantifying gains and impacts.
Position
OPPO proposes defining a specific BS reference configuration (Set 4) for ~7GHz operation with 200MHz BW and 256 Tx/Rx RUs for 6G energy efficiency evaluation. They propose extending the UE power model by introducing a new power state ('Deep-sleep 2') between Deep-sleep and Ultra Deep-sleep with specific power and transition values, and extending bandwidth adaptation scaling down to 3MHz. For network energy saving, they evaluate clustered SSB transmission with intra-5ms repetition and propose UE-triggered wake-up for both coverage and capacity cells, supported by 'light SSB' candidate techniques. They propose a two-stage PDCCH design where a first compact stage (potentially sequence-based) facilitates full second-stage detection to natively embed energy efficiency into the 6G DL control channel.
Key proposals
- Proposal 1 (Sec 2.1.1): For evaluation purpose, RAN1 to confirm the following reference configuration for BS power model with a set for around 7GHz operation with defined parameters.
- Proposal 4 (Sec 2.2.1.1): Single cell multi-carrier power model can use the scaling method to determine the SCMC BS power model.
- Proposal 6 (Sec 2.2.2): For 6GR eMBB UE, the TR 38.840/ TR 38.869 model is the starting point for UE power model with introduction of a new power state, extending power scaling for bandwidth adaptation, and supporting low/high capability modes.
- Proposal 7 (Sec 2.3): The 5G basic metrics can be reused, while for power consumption evaluation, apart from separate evaluation for BS and UE, 6GR may also consider a metric reflecting joint BS and UE power consumption.
- Proposal 9 (Sec 3.1.2): 6GR can consider 'light SSB' and OD-SSB as candidate techniques for EE study.
- Proposal 11 (Sec 3.1.3): For the 6GR, the following study can be considered: support of OD-SIB1 with and without relying on cell A, low radio UL-WUS based OD-SIB1 request, and more efficient type0-PDCCH monitoring for UE energy saving.
- Proposal 12 (Sec 3.2.1): Multi-hypotheses CSIs for spatial domain NES (e.g., type 1 SD and type 2 SD in Rel-18) can be studied within CSI framework of 6G MIMO, considering collaboration with CSI-RS overhead reduction and CSI compression with reduced CSI feedback overhead.
- Proposal 15 (Sec 3.3.2): Cell DTX/DRX can be considered in 6GR for energy saving, and it should be applicable to all RRC states.
- Proposal 19 (Sec 4.1.1): Study Single Cell with Multiple Carriers (SCMC) for 6G EE improvement.
- Proposal 20 (Sec 4.1.2): Multiple functionality-sets transforming is supported in bandwidth adaptation mechanism with dynamic change in set of parameters, including a mandatory baseline functionality set commonly supported by all UEs.
- Proposal 21 (Sec 4.2): The design of DL control in 6G shall natively support energy efficient operations. PDCCH should consider two stage indications: first stage with compact indication, second stage corresponds to full detection.
- Proposal 24 (Sec 4.4): The energy saving procedures are naturally enabled in the baseline 6G operation with PDCCH monitoring adaptation and Lower Power Wake-up as first-stage for PDCCH monitoring.
- Proposal 25 (Sec 4.5): 6GR UL control should consider sparse UCI transmission to improve UL efficiency and reduce power consumption.