5.4 Channel arrangement

38.521-23GPPNRPart 2: Range 2 StandaloneRadio transmission and receptionRelease 17TSUser Equipment (UE) conformance specification

5.4.1 Channel spacing

5.4.1.1 Channel spacing for adjacent NR carriers

The spacing between carriers will depend on the deployment scenario, the size of the frequency block available and the channel bandwidths. The nominal channel spacing between two adjacent NR carriers is defined as following:

For NR operating bands with 60 kHz channel raster,

Nominal Channel spacing = (BW_Channel(1) + BW_Channel(2))/2 + {-20 kHz, 0 kHz, 20 kHz} for ∆F_Raster equals to 60 kHz

Nominal Channel spacing = (BW_Channel(1) + BW_Channel(2))/2 + {-40 kHz, 0 kHz, 40 kHz} for ∆F_Raster equals to 120 kHz

where BW_Channel(1) and BW_Channel(2) are the channel bandwidths of the two respective NR carriers. The channel spacing can be adjusted depending on the channel raster to optimize performance in a particular deployment scenario.

5.4.2 Channel raster

5.4.2.1 NR-ARFCN and channel raster

The global frequency raster defines a set of RF reference frequencies F_REF. The RF reference frequency is used in signalling to identify the position of RF channels, SS blocks and other elements.

The global frequency raster is defined for all frequencies from 0 to 100 GHz. The granularity of the global frequency raster is ΔF_Global.

RF reference frequency is designated by an NR Absolute Radio Frequency Channel Number (NR-ARFCN) in the range [2016667…3279165] on the global frequency raster. The relation between the NR-ARFCN and the RF reference frequency F_REF in MHz is given by the following equation, where F_REF-Offs and N_Ref-Offs are given in Table 5.4.2.1-1 and N_REF is the NR-ARFCN

F_REF = F_REF-Offs + ΔF_Global (N_REF – N_REF-Offs)

Table 5.4.2.1-1: NR-ARFCN parameters for the global frequency raster

Frequency range (MHz)	ΔFGlobal (kHz)	FREF-Offs (MHz)	NREF-Offs	Range of NREF
24250 – 100000	60	24250.08	2016667	2016667 – 3279165

The channel raster defines a subset of RF reference frequencies that can be used to identify the RF channel position in the uplink and downlink. The RF reference frequency for an RF channel maps to a resource element on the carrier. For each operating band, a subset of frequencies from the global frequency raster are applicable for that band and forms a channel raster with a granularity ΔF_Raster, which may be equal to or larger than ΔF_Global.

The mapping between the channel raster and corresponding resource element is given in subclause 5.4.2.2. The applicable entries for each operating band are defined in subclause 5.4.2.3

5.4.2.2 Channel raster to resource element mapping

The mapping between the RF reference frequency on channel raster and the corresponding resource element is given in Table 5.4.2.2-1 and can be used to identify the RF channel position. The mapping depends on the total number of RBs that are allocated in the channel and applies to both UL and DL. The mapping must apply to at least one numerology supported by the UE.

Table 5.4.2.2-1: Channel raster to resource element mapping

Resource element index	0	6
Physical resource block number

, , are as defined in TS 38.211[9].

5.4.2.3 Channel raster entries for each operating band

The RF channel positions on the channel raster in each NR operating band are given through the applicable NR-ARFCN in Table 5.4.2.3‑1, using the channel raster to resource element mapping in subclause 5.4.2.2.

– For NR operating bands with 60 kHz channel raster above 24 GHz, ΔF_Raster = I ×ΔF_Global, where I ϵ {1,2}. Every I^th NR‑ARFCN within the operating band are applicable for the channel raster within the operating band and the step size for the channel raster in Table 5.4.2.3-1 is given as <I>.

– In frequency bands with two ΔF_Raster, the higher ΔF_Raster applies to channels using only the SCS that is equal to the higher ΔF_Raster and the SSB SCS that is equal to or larger than the higher ΔF_Raster.

Table 5.4.2.3-1: Applicable NR-ARFCN per operating band

Operating Band	ΔFRaster (kHz)	Uplink and Downlink Range of NREF (First – <Step size> – Last)
n257	60	2054166 – <1> – 2104165
	120	2054167 – <2> – 2104165
n258	60	2016667 – <1> – 2070832
	120	2016667 – <2> – 2070831
n259	60	2270833 – <1> – 2337499
	120	2270833– <2> – 2337499
n260	60	2229166 – <1> – 2279165
	120	2229167 – <2> – 2279165
n261	60	2070833 – <1> – 2084999
	120	2070833 – <2> – 2084999

5.4.3 Synchronization raster

5.4.3.1 Synchronization raster and numbering

The synchronization raster indicates the frequency positions of the synchronization block that can be used by the UE for system acquisition when explicit signalling of the synchronization block position is not present.

A global synchronization raster is defined for all frequencies. The frequency position of the SS block is defined as SS_REF with corresponding number GSCN. The parameters defining the SS_REF and GSCN for all the frequency ranges are in Table 5.4.3.1-1.

The resource element corresponding to the SS block reference frequency SS_REF is given in subclause 5.4.3.2. The synchronization raster and the subcarrier spacing of the synchronization block are defined separately for each band.

Table 5.4.3.1-1: GSCN parameters for the global frequency raster

Frequency range	SS block frequency position SSREF	GSCN	Range of GSCN
24250 – 100000 MHz	24250.08 MHz + N * 17.28 MHz, N = 0: 4383	22256+ N	22256 – 26639

5.4.3.2 Synchronization raster to synchronization block resource element mapping

The mapping between the synchronization raster and the corresponding resource element of the SS block is given in Table 5.4.3.2-1.

Table 5.4.3.2-1: Synchronization raster to SS block resource element mapping

Resource element index k

120

k is the subcarrier number of SS/PBCH block defined in TS 38.211 [9] clause 7.4.3.1.

5.4.3.3 Synchronization raster entries for each operating band

The synchronization raster for each band is given in Table 5.4.3.3-1. The distance between applicable GSCN entries is given by the <Step size> indicated in Table 5.4.3.3-1.

Table 5.4.3.3-1: Applicable SS raster entries per operating band

NR Operating Band	SS Block SCS	SS Block pattern1	Range of GSCN (First – <Step size> – Last)
n257	120 kHz	Case D	22388 – <1> – 22558
	240 kHz	Case E	22390 – <2> – 22556
n258	120 kHz	Case D	22257 – <1> – 22443
	240 kHz	Case E	22258 – <2> – 22442
n259	120 kHz	Case D	23140 – <1> – 23369
	240 kHz	Case E	23142 – <2> – 23368
n260	120 kHz	Case D	22995 – <1> – 23166
	240 kHz	Case E	22996 – <2> – 23164
n261	120 kHz	Case D	22446 – <1> – 22492
	240 kHz	Case E	22446 – <2> – 22490
NOTE 1: SS Block pattern is defined in subclause 4.1 in TS 38.213 [22].