Content for  TR 21.917  Word version:  17.0.1

Summary based on the input provided by Huawei in RP-221505. The technical work on 6425-7125 MHz frequency range follows the RCC Recommendation 1/21 [2]. In order to make this frequency range available for IMT licensed usage, this work item has specified BS/UE RF requirements for licensed operation in the range of 6425- 7125 MHz, including:

• Band plan for licensed operation in the range of 6425- 7125 MHz
• System parameters such as channel bandwidths and channel arrangements
• UE transmitter and receiver characteristics
• BS transmitter and receiver characteristics

Operating band NR operating band n104 is designed to operate in the range of 6425- 7125 MHz. The duplex mode is TDD.

System parameters

• BS/UE channel bandwidth (in MHz): 20, 30, 40, 50, 60, 70, 80, 90, 100
• Channel raster granularity: 15 kHz and 30 kHz
• Synchronization raster step size: 7

UE transmitter and receiver characteristics UE transmitter and receiver RF requirements for Band n104 are added to TS 38.101-1. The following band specific UE RF requirements are defined for Band n104. The detailed RF requirements can be found in the CR [3].

• UE Power Class 2 and Power Class 3
• Spurious emissions for UE co-existence
• UE reference sensitivity
• In-band blocking parameters
• Out-of-band blocking

BS transmitter and receiver characteristics BS transmitter and receiver RF requirements for Band n104 are added to TS 38.104. The following band specific BS RF requirements are defined for Band n104. The detailed RF requirements can be found in the CR [4].

• Maximum offset of OBUE outside the downlink operating band
• Adjacent Channel Leakage power Ratio (ACLR)
• Operating band unwanted emission limits
• BS reference sensitivity
• Dynamic range
• Adjacent Channel Selectivity (ACS)
• OOB offset for NR operating band
• BS type 1-C Out-of-band blocking
• In-channel selectivity

Impacted existing TS RAN4 has agreed the following CRs:

Summary based on the input provided by Qualcomm in RP-222478. This WID extends NR operation to 71GHz with the introduction of new unlicensed band n263. Relevant system parameters have been updated to consider the new sub-frequency range FR2-2, larger subcarrier spacings and channel bandwidths. This NR extension includes definition of n263 requirements for various form-factors (PC1, PC2, PC3), for both single carrier and CA operation. Introduction NR Rel-15 defined two frequency ranges for operation: FR1 spanning from 410 MHz to 7.125 GHz and FR2 spanning from 24.25 GHz to 52.6 GHz. RAN carried out a Rel-16 study on NR beyond 52.6 GHz (FS_NR_beyond_52GHz) with corresponding TR in 38.807. From this study, it became apparent the global availability of bands in the 52.6 GHz to 71 GHz range, most notably in the form of the original 60 GHz band (57-66 GHz) and extended 60 GHz band (57-71 GHz). Moreover, WRC19 recently identified the 66-71 GHz frequency range for IMT operation in certain regions. The proximity of this frequency range (57-71 GHz) to FR2 and the imminent commercial opportunities for high data rate communications makes it compelling for 3GPP to address NR operation in this frequency regime. To minimize the specification burden and maximize the leverage of FR2 based implementations, 3GPP has decided to extend FR2 operation up to 71 GHz with the adoption of one or more new numerologies (i.e., larger subcarrier spacings). Those new numerologies were identified in the study on waveform for NR>52.6 GHz in the first half of 2020. NR-U defined procedures for operation in unlicensed spectrum were also leveraged towards operation in the unlicensed 60 GHz band. RAN1 completed a Rel-17 study on supporting NR from 52.6 GHz to 71 GHz. Subcarrier spacing (SCS) of 120 kHz with NCP was recommended to be supported. New subcarrier spacings 480 kHz, and 960 kHz along with 120 kHz were introduced for this frequency range. The spec impact for each subcarrier spacing choice was identified. Additional areas for further physical layer enhancements were also identified. For channel access, both LBT mode and no-LBT mode were recommended to be supported to cover a wide range of use cases and regulatory requirements. For LBT mode, the channel access mechanism defined in EN 302 567 was identified as the baseline and enhancements were chosen for further discussion. The objectives of this work item are presented below. Physical layer aspects including [RAN1] In addition to 120 kHz SCS, specify new SCS, 480 kHz and 960 kHz, and define maximum bandwidth(s), for operation in this frequency range for data and control channels and reference signals, only NCP supported. Note: Except for timing line related aspects, a common design framework shall be adopted for 480 kHz to 960 kHz Timeline related aspects adapted to 480 kHz and 960 kHz, e.g., BWP and beam switching timing, HARQ timing, UE processing, preparation and computation timelines for PDSCH, PUSCH/SRS and CSI, respectively. Support of up to 64 SSB beams for licensed and unlicensed operation in this frequency range. Supports 120 kHz SCS for SSB and 120 kHz SCS for initial access related signals/channels in an initial BWP. Study and specify, if needed, additional SCS (480 kHz, 960 kHz) for SSB for cases other than initial access. Note: coverage enhancement for SSB is not pursued. In addition to 120 kHz, support 480 kHz SSB for initial access with support of CORESET#0/Type0-PDCCH configuration in the MIB with following constraints:

• Limited sync raster entry numbers. It is assumed that RAN4 supports a channelization design which results in the total number of synchronization raster entries considering both licensed and unlicensed operation in a 52.6 - 71 GHz band no larger than 665 (Note: the total number of synchronization raster entries in FR2 for band n259 + n257 is 599). If the assumption cannot be satisfied, it's up to RAN4 to decide its applicability to bands in 52.6 - 71 GHz.
• only 480 kHz CORESET#0/Type0-PDCCH SCS supported for 480 kHz SSB SCS.
• Prioritize support SSB-CORESET#0 multiplexing pattern 1. Other patterns discussed on a best effort basis.
• 960 kHz numerology for the SSB is not supported by the UE for initial access in Rel-17.
• Note: Strive to minimize specification impact by reusing tables for CORESET#0 and type0-PDCCH CSS set configuration defined for FR2 in Rel-15, as much as possible
• Note: 480 kHz is an optional SSB numerology for initial access for the UE. A UE supporting a band in 52.6-71 GHz must at least support 120 kHz SCS (for initial access and after initial access)
• Note: Dependency or lack thereof for a UE supporting 480 kHz and/or 960 kHz numerology for data and control to also support 480 kHz SSB numerology for initial access is to be tackled as part of UE capability discussion.

Support ANR and PCI confusion detection for 120, 480 and 960 kHz SCS based SSB, support CORESET#0/Type0-PDCCH configuration in MIB of 120, 480 and 960 kHz SSB

• FFS: additional method(s) to enable support to obtain neighbour cell SIB1 contents related to CGI reporting
• Only 1 CORESET#0/Type0-PDCCH SCS supported for each SSB SCS, i.e., (120, 120), (480, 480) and (960, 960).
• Prioritize support SSB-CORESET#0 multiplexing pattern 1. Other patterns discussed on a best effort basis.
• Note: Strive to minimize specification impact by reusing tables for CORESET#0 and type0-PDCCH CSS set configuration defined for FR2 in Rel-15, as much as possible
• Note: From UE perspective, ANR detection for 480/960 kHz SCS based SSB is not supported if the UE does not support 480/960 SCS for SSB.
• Note: for ANR, when reading the MIB, the cell containing the SSB is known to the UE, as defined in 38.133 specification.

Specify timing associated with beam-based operation to new SCS (i.e., 480 kHz and/or 960 kHz), study, and specify if needed, potential enhancement for shared spectrum operation: Rel-15/16 and any Rel-17 beam management enhancements can be considered for 52.6-71 GHz. Whether particular features should be excluded for 52.6-71 GHz can be further discussed. Note: As per usual procedure, duplication of work between work items in Rel-17 should be avoided Support enhancement for PUCCH format 0/1/4 to increase the number of RBs under PSD limitation in shared spectrum operation. Support enhancements for multi-PDSCH/PUSCH scheduling and HARQ support with a single DCI. Note: coverage enhancement for multi-PDSCH/PUSCH scheduling is not pursued Support enhancement to PDCCH monitoring, including blind detection/CCE budget, and multi-slot span monitoring, potential limitation to UE PDCCH configuration and capability related to PDCCH monitoring. Specify support for PRACH sequence lengths (i.e., L=139, L=571 and L=1151) and study, if needed, specify support for RO configuration for non-consecutive RACH occasions (RO) in time domain for operation in shared spectrum Evaluate, and if needed, specify the PTRS enhancement for 120 kHz SCS, 480 kHz SCS and/or 960 kHz SCS, as well as DMRS enhancement for 480 kHz SCS and/or 960 kHz SCS. Physical layer procedure(s) including [RAN1] Channel access mechanism assuming beam-based operation in order to comply with the regulatory requirements applicable to unlicensed spectrum for frequencies between 52.6 GHz and 71 GHz.

• Specify both LBT and No-LBT related procedures, and for No-LBT case no additional sensing mechanism is specified.
• Study, and if needed specify, omni-directional LBT, directional LBT and receiver assistance in channel access
• Study, and if needed specify, energy detection threshold enhancement

Radio interface protocol architecture and procedures [RAN2]: For operation in this frequency range: Introduce higher layer support of enhancements listed above that are agreed to be specified. Note: RAN2 is to prioritize protocol support of RAN1 design and not on optimizations on items not discussed in RAN1. Core specifications for UE, gNB and RRM requirements [RAN4]: Specify new band(s) for the frequency range from 52.6 GHz-71 GHz. The band(s) definition should include UL/DL operation and excludes ITS spectrum in this frequency range. Specify gNB and UE RF core requirements for the band(s) in the above frequency range, including a limited set of example band combinations (see Note 1). For the case of FR2-2 DC or CA with an anchor in FR1 the following three example band combinations shall be considered: n79 + Nx ; n77 + Nx and n41 + Nx , where Nx is the 57-71 GHz band for unlicensed operation and the [66-71] GHz for licensed operation. RAN4 to further discuss the need for single or multiple bands relevant for FR2-2 licensed/unlicensed operation. Specify RRM/RLM/BM core requirements. Notes: The WI can be completed provided requirements for at least one band combination involving a new NR-U band is specified as long as it is in line with country-specific regulatory directives. UEs supporting a band in the range of 52.6 GHz-71 GHz are not required to support 480 kHz SCS and 960 kHz SCS. The maximum FFT size required to operate the system in 52.6 GHz-71 GHz frequency is 4096, and the maximum of RBs per carrier is 275 RBs. The system is designed to support both single-carrier and multi-carrier operation. FR2 is extended to cover 24.25 GHz to 71 GHz with FR2-1 for 24.25-52.6 GHz and FR2-2 for 52.6-71 GHz. The related UE capabilities and their applicability to the frequency range 52.6 to 71 GHz will have to be analyzed on a case-by-case basis The application of any of the UE feature introduced for 52.6-71 GHz to existing FR1/FR2 should be discussed case by case. TSG RAN specifications shall make it very clear (to readers) that frequency bands in the 52.6-71 GHz range are only Release-independent from Rel-17 onwards, to ensure that there is clear industry understanding about which FR2 features are applicable for operation in 52.6-71 GHz range. Notes: Whenever the FR2 is referred, both FR2-1 and FR2-2 frequency sub-ranges shall be considered in this release, unless otherwise stated. The designations FR2-1 and FR2-2 should only be used when needed. Description Similar to regular NR and NR-U operations below 52.6 GHz, NR/NR-U operation in the 52.6 GHz to 71 GHz can be in stand-alone or aggregated via CA or DC with an anchor carrier. Physical Layer enhancements In addition to 120 kHz SCS already supported in FR2-1, new SCSs of 480 kHz and 960 kHz are introduced, that can support wider bandwidth up to 2 GHz. For operation in FR2-2, SCSs 480 kHz and 960 kHz are optionally supported by UE, while SCS 120 kHz is mandatory. Initial access aspects SSB of SCS 120 kHz, 480 kHz and 960 kHz are supported in FR2-2, and SCS 120 kHz and 480 kHz SSBs can support initial access. Up to 64 SSB candidate positions are allowed for FR2-2 and Discovery Burst Transmission Window (DBTW) is supported with ssb-PositionQCL being 32 or 64. CORESET#0/Type0-PDCCH SCS is always the same as SSB SCS. SSB-CORESET#0 multiplexing pattern 1 and pattern 3 are supported for FR2-2. Time locations for SCS 120 kHz SSB in FR2-1 are reused for FR2-2. Time locations for SCS 480 kHz and SCS 960 kHz SSBs are newly defined. For PRACH, length 139 sequence is supported for all SCS, length 571 sequence is supported for SCSs 120 kHz and 480 kHz, and length 1151 sequence is supported for SCS 120 kHz. PDCCH monitoring enhancements For SCS 480 kHz and 960 kHz, since slots are short, and UE power consumption to monitor PDCCH in each slot will be high, multi-slot PDCCH monitoring capability is introduced where UE monitors PDCCH in Y slots out of every X slots. Enhancements for PUCCH formats 0/1/4 To support higher transmit power under PSD limitation for PUCCH formats 0/1/4, enhanced PUCCH formats 0/1/4 are supported such that the number of RBs can be RRC configured from 1 to 16. For PUCCH format 0/1, type-1 long sequence occupying all REs over the configured number of RBs is used. For PUCCH format 4, OCC 2 or 4 is supported, and the number of RBs is restricted to in the form of N_RB=2^(α_2 )∙3^(α_3 )∙5^(α_5 ). Beam managements for new SCSs Beam switching related timing values for SCS 480 kHz and 960 kHz are defined. PDSCH/PUSCH enhancements Multi-PDSCH scheduling with a single DCI and multi-PUSCH scheduling with a single DCI are supported, where the time domain allocations of the multiple PDSCH or multiple PUSCH can be discontinuous. Time domain HARQ-ACK bundling is supported for both Type 1 HARQ codebook and Type 2 HARQ codebook. Processing timelines for 480 kHz and 960 kHz SCS are defined, such as HARQ timeline, UE processing timeline, etc. DMRS enhancements for 480 kHz and 960 kHz are introduced that allows the indication to the UE that FD OCC is disabled for rank 1 transmission. The maximum number of HARQ processes supported for FR2-2 are increased to 32 in both DL and UL. Channel access mechanism In frequency range 2-2, Rel-17 NR supports licensed spectrum operation (Draft CRs for FR2-2 licensed band n264 were endorsed, but won't be agreed until the regulation is available in at least one country or region), shared spectrum operation with LBT and shared spectrum operation without LBT. gNB will indicate UE if LBT is used for channel access by higher layer signalling. When LBT mode is enabled, a maximum channel occupancy time (COT) of 5ms is supported. COT sharing from gNB to UE and UE to gNB are supported, similar to Release 16 NR-U. For channel access for LBT mode, 3 types of channel access are defined

• Type 1 channel access can be performed by gNB or UE to initiate a channel occupancy. Type 1 channel access involves sensing the channel multiple times with a counter with maximum contention window size 3.
• Type 2 channel access requires a single sensing slot channel sensing and can be used to share a COT.
• Type 3 channel access does not require channel sensing and can be used to share a COT, or to initiate Discovery RS transmission when regulation allows.

The directional LBT is defined for gNB and UE with or without beam correspondence. The bandwidth on which LBT is performed by gNB/UE should at least include active DL/UL BWP bandwidth. MAC Enhancements Rel-16 NR-U has introduced several enhancements to MAC procedures to alleviate the impact of LBT mechanism which can cause delays or dropped transmissions. The following were also adopted for FR2-2: Consistent LBT failure detection and recovery; Configured Grant (CG) changes; Changes to RACH procedures (e.g., extended RAR window duration) and HARQ handling for uplink multi-TTI transmissions. Consistent LBT failure detection and recovery is applicable to FR2-2 with no changes, assuming LBT is configured on the considered serving cell. The changes to configured grant transmission in Rel-16 NR-U were mainly due to autonomous retransmission on CG resources, autonomous HARQ process ID. and RV selection. A new CG retransmission timer was introduced where the UE is allowed to retransmit a packet on a CG after this timer expires without any ACK from the gNB for the earlier transmission. The only change for FR2-2 is that this timer is now optional and configured by RRC. Thus, when the timer is configured, the UE follows Rel-16 NR-U procedures while it uses the licensed spectrum procedures otherwise. For FR2-2, extended values were introduced for several DRX parameters due to the shorter symbol duration for SCS of 480 and 960 kHz. Upper Layer Enhancements The support of RSSI and Channel Occupancy (CO) measurements was also carried over to FR2-2. For FR2-2, the configuration can also include bandwidth serving cell and TCI information for the RSSI measurement. The enhancements to Idle/Inactive mode mobility (due to the possible existence of multiple independent operators on the same carrier) and paging (multiple paging monitoring occasions per PO) for NR-U are also re-used in FR2-2. We note that Channel Access Priority Class (CAPC) which is used for QoS in NR-U as well as LTE LAA are not applicable to FR2-2. Since LBT is optional for FR2-2, a new parameter is broadcast in SIB1 to indicate the LBT mode. The same information for neighbor cells can be included in measurement object for RRM and SIB3/SIB4 for Idle/Inactive mobility (RAN2 is still discussing this). Many RRC parameters with values dependent on symbol duration or bandwidth were enhanced to support the new SCS and bandwidths. The legacy UE capabilities which had FR1/FR2 differentiation in Rel-15/16 required, in some cases, further differentiation between legacy FR2 and FR2-2. These capabilities also included some upper layer capabilities such as IMS voice, Rel-16 Power Saving, and Rel-16 DCCA. For the new UE capabilities which needed FR2-2 differentiation, per-band signaling was adopted with consistent signaling across the FR2 bands. New signaling and procedures were also introduced in LTE specifications to support handover from E-UTRAN to NR FR2-2. System parameters Spectrum and operating band FR2 has been divided into two sub-frequency ranges: FR2-1 which covers the original range of 24.25-52.6 GHz, and FR2-2 which extends NR operation from 52.6 to 71 GHz. Given the prevalence of unlicensed spectrum in this frequency range, a new NR band for unlicensed operation was introduced in this work item, band n263. This band extends from 57 to 71GHz, ensuring the unlicensed spectrum of all regions is supported.

Channel arrangement UE channel bandwidth for n263: Compared to FR2-1, FR2-2 supports larger channel bandwidths including 800, 1600 and 2000MHz. In this release, only 400MHz channel bandwidth support is mandatory for band n263. An optional capability enables the UE to indicate its supported channel bandwidths for 480 and 960kHz SCS [3]. Channel spacing for band n263:

Channel raster: Band n263 is defined to support 138 entries of non-overlapping 100MHz CBW with 100.8MHz channel spacing, 34 entries of non-overlapping 400MHz CBW with 403.2MHz channel spacing, and 30 to 34 entries of overlapping 800, 1600, and 2000MHz CBW that are spaced part by 403.2MHz. Additionally, band n263 supports one 120kHz SCS-based synchronization raster entry for each 100MHz CBW, and one 480kHz SCS-based synchronization raster entry for 400MHz CBW. Initial access using 960kHz SCS is not supported. Core requirements Extending requirement definition to 71GHz Many core requirements, either their definition or approach used to define them in FR2-1, were reused in FR2-2. For example, given the highly integrated nature of designs in this frequency range, characteristics continue to be specified over-the-air in FR2-2. As with FR2-1, minimum performance requirements for FR2-2 were defined per-band and per-UE power class. Tx and Rx requirements were defined for power class 1 (FWA UE), power class 2 (vehicular UE), and power class 3 (handheld UE) operation in band n263. These power classes use the same reference form-factor used in FR2-1, but the number of antenna elements used to derive the requirements was increased to help alleviate the impact of higher losses and more complex integration of this frequency range. Carrier aggregation in FR2-2 In addition to single carrier requirements, FR2-2 requirements to support intra-band contiguous CA operation have also been defined. In this release, contiguous DL CA configurations within FR2-2 may only contain multiples of the same channel bandwidth. The supported CA band combinations include FR2-2 with an FR1 anchor; combinations for n48 + n263 were introduced in RAN4 #104e [4]. Beam correspondence For band n263, support of beam correspondence without UL beam sweeping is defined for power class 3.