R1-2601780
discussion
6G General Aspects and Frameworks
From FUTUREWEI
FUTUREWEI's prior position on
10.5.0
at
RAN1#124
· AI-synthesized, paraphrased
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Proposes agreeing to Opt1 for SSB design with bandwidth larger than 3MHz and selecting a single maximum bandwidth option to limit device types and maximize economies of scale. Proposes redefining the serving cell concept to support multiple carriers with intra-cell CA using one PCC for control/RRC and one or more SCCs for data exchange, forming a 2-level CA framework (intra-cell and inter-cell CA). For 400MHz support, proposes 2x 200MHz RF chains with 2x 8k FFT and considers 1x 400MHz RF chain options. Argues coverage range in meters is the most direct metric rather than a single MCL/MIL/MPL value. Proposes studying SCS options for around 15GHz and supporting TDD, FDD, SBFD, and HD-FDD duplex modes from day one, while further investigating SBFD/SSFD impact on frame structure. For initial access energy efficiency, proposes transmitting MIB/SIB1 with larger periodicities than synchronization signals or on-demand, supporting on-demand SSB/SIB1, and time-adaptive/flexible scalable PRACH from Day 1.
Summary
Futurewei presents 7 proposals and 9 observations on 6G Radio frameworks, covering maximum bandwidth interpretations, UE 400MHz DL support options, intra-cell and inter-cell carrier aggregation, smallest maximum UE bandwidth for low-tier devices, and initial access design criteria for a unified 6GR framework spanning fragmented and contiguous spectrum deployments.
Position
Futurewei proposes studying intra-cell carrier aggregation (Method 1 'Gothia cell') using multiple contiguous/non-contiguous physical carriers up to 400 MHz logical bandwidth, and inter-cell carrier aggregation including FR1+FR2 non-collocated scenarios with possible DC-like realization. They require prioritization of Option 1 as the clean reference for contiguous wideband operation, with Option 2 or Option 3 as practical implementation candidates subject to RAN4 feasibility. They propose that the smallest maximum supported RF and BB UE BW for lowest-tier devices is 20MHz, arguing that 5MHz HD-FDD devices cannot meet RAN peak data rate requirements and that overall device complexity is driven by economies of scale. They propose studying a common initial-access framework where DL and UL IA bandwidth share center frequencies and are contained in the same carrier, supporting transition to post-IA wideband operation under both aggregation frameworks.
Key proposals
- Proposal 1 (Discussions of UE 400MHz DL support): Study intra-cell carrier aggregation within one cell using multiple contiguous and/or non-contiguous physical carriers spanning up to 400 MHz logical bandwidth.
- Proposal 2 (Discussions of UE 400MHz DL support): Study inter-cell carrier aggregation for access to spectrum distributed across multiple cells in FR1, including contiguous intra-band, non-contiguous intra-band, and inter-band scenarios.
- Proposal 3 (Discussions of UE 400MHz DL support): Study FR1+FR2 spectrum aggregation for non-collocated deployment scenarios, including cases that may require inter-cell carrier aggregation and DC-like realization in deployment.
- Proposal 4 (Discussions of UE 400MHz DL support): Prioritize the study of Option 1 as the clean reference for contiguous wideband operation and Option 2 or Option 3 as most practical implementation candidates subject to RAN4 feasibility.
- Proposal 5 (Discussions of UE 400MHz DL support): Identify the constraints and study the solutions for cases where UE instantaneous DL BW support is up to 400 MHz under a common logical wideband resource while UL instantaneous BW is up to 200 MHz.
- Proposal 6 (Smallest maximum BW): The smallest maximum supported RF and BB UE BW for the lowest-tier device type is 20MHz. The possibility of uplink PRB restrictions will be considered later during the detailed device type discussion.
- Proposal 7 (6GR Initial Access Design Criteria): Study how a common and efficient initial-access framework can support transition from IA/common-anchor bandwidth to post-IA wideband operation under both intra-cell and inter-cell aggregation frameworks.