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> Provide an extensive summary of the agreements by topic. No need to mention CRs.

Summary of Agreements by Topic

1. Scenarios Applicable to NB-IoT/eMTC

• Three main scenarios were agreed upon for IoT NTN:
• Scenario A: GEO-based non-terrestrial access network.
• Scenario B: LEO-based non-terrestrial access network with steerable beams.
• Scenario C: LEO-based non-terrestrial access network with fixed beams moving with the satellite.
• MEO-based non-terrestrial access network (Scenario D) was added later, with specific parameters for altitude, beam footprint size, and round-trip delay.

2. Enhancements to Time and Frequency Synchronization

• GNSS Position Fix:
• GNSS position fix validity duration was defined with values ranging from 10 seconds to infinity.
• UE autonomously determines GNSS validity duration and reports it to the network.
• Ephemeris Information:
• Support for two ephemeris formats: state vectors (position/velocity) and orbital parameters.
• Epoch time signaling was clarified for both SIB and dedicated signaling.
• Pre-compensation:
• UE pre-compensation for uplink transmission was agreed to be adjusted per segment.
• Methods for pre-compensation include dropping samples, blanking subframes, or puncturing OFDM symbols.
• Validity Timer:
• A single validity timer for UL synchronization was defined, with durations ranging from 5 to 240 seconds.
• Timer starts/restarts with the epoch time of assistance information.

3. Timing Relationship Enhancements

• Koffset and Kmac:
• Cell-specific Koffset is used for NPDCCH and MPDCCH ordered NPRACH and PRACH timing relationships.
• Koffset and Kmac units were defined as 1 ms for 3.75 kHz subcarrier spacing.
• HARQ Timing:
• HARQ-ACK reporting procedures were updated to include Koffset for NTN functionality.
• Random Access:
• Timing relationships for random access procedures initiated by NPDCCH or MPDCCH orders were clarified.
• Processing Time:
• eNB ensures Koffset is set to be larger or equal to the sum of service link RTT and common TA.

4. UL Segmented Transmission

• UE behavior for gaps between uplink transmission segments was clarified:
• UE may drop durations such as 1 slot, 1 subframe, or 1 symbol between segments.
• Legacy behavior applies when capability is not signaled.
• UL transmission segment duration was configured via system information or dedicated RRC signaling.

5. SIB Accumulation

• SIB accumulation across SI windows for IoT NTN was agreed to be optionally supported by UE implementation without specification impact.

6. Interference Randomization

• Interference randomization for NB-IoT was discussed but not pursued for Rel-17.

7. Miscellaneous Agreements

• Epoch Time:
• SFN ambiguity for epoch time was resolved by reusing solutions from NR NTN.
• UE Capability:
• UE capability parameter names were corrected for pre-compensation in segments.
• Downlink Reception:
• Minimum physical time for processing downlink channels/signals was aligned with terrestrial networks.

This summary captures the key agreements across various topics discussed during the study and maintenance phases of NB-IoT/eMTC support for Non-Terrestrial Networks.