NR-ARFCN

NR Absolute Radio Frequency Channel Number

Identifier →
Introduced in Rel-15

NR-ARFCN is the unique numerical identifier used in 5G NR to specify a radio channel's center frequency for standardized frequency referencing, band management, and ensuring interoperability.

Category
Identifier
Introduced
Rel-15
Where
Radio Access Network › NG-RAN (5G)
Specifications
23 specs
NR-ARFCN Description Purpose Detected Changes Specifications

Description

The NR Absolute Radio Frequency Channel Number (NR-ARFCN) is a critical parameter in 5G New Radio (NR) that unambiguously defines the center frequency of a carrier or channel. It serves as a digital label mapped to a specific radio frequency, simplifying frequency specification in protocols and configurations. The mapping is defined by a linear formula: the center frequency F (in MHz) is calculated as F = F_ref + ΔF * (N – N_ref), where N is the NR-ARFCN value, F_ref is a reference frequency, N_ref is a reference NR-ARFCN, and ΔF is the channel raster step size (e.g., 5 kHz, 15 kHz, 60 kHz depending on the band and scenario). This system allows for precise frequency identification across the wide spectrum used by NR, from sub-1 GHz to millimeter wave bands.

NR-ARFCN operates within two primary frequency ranges: Frequency Range 1 (FR1: 410 MHz – 7.125 GHz) and Frequency Range 2 (FR2: 24.25 GHz – 52.6 GHz). Each range has its own set of parameters for the mapping formula to accommodate different channel rasters and band characteristics. For example, in FR1, the global channel raster is typically 100 kHz for synchronization signal blocks (SSB) but can be as fine as 5 kHz for other channels, while FR2 uses larger steps due to wider bandwidths. The NR-ARFCN values are allocated in specific ranges for each operating band to avoid ambiguity and ensure global consistency.

In the network, NR-ARFCN is used extensively in signaling and configuration messages. During initial access, the gNB broadcasts synchronization signal blocks (SSB) associated with specific NR-ARFCNs to help user equipment (UE) detect and camp on the cell. In Radio Resource Control (RRC) signaling, NR-ARFCN identifies carriers for operations like carrier aggregation, dual connectivity, and handovers. It also plays a role in band support indication, where UEs report their supported bands using NR-ARFCN ranges. This identifier is fundamental to frequency management, enabling dynamic spectrum sharing, efficient resource allocation, and multi-band operations in 5G networks.

Purpose & Motivation

NR-ARFCN was introduced to address the need for a unified and scalable frequency identification system in 5G NR, overcoming limitations of earlier systems like LTE's EARFCN. As 5G expanded into new spectrum bands, including millimeter wave frequencies with wider bandwidths and diverse channel arrangements, a more flexible identifier was required. The purpose is to provide a standardized method for referencing any NR carrier frequency globally, ensuring interoperability between network equipment and devices from different vendors.

Historically, each cellular generation had its own channel numbering scheme (e.g., ARFCN for GSM, UARFCN for UMTS, EARFCN for LTE). With 5G's broader frequency range and varied use cases, the previous schemes were inadequate due to fixed granularity and limited range. NR-ARFCN solves this by offering a linear mapping that can scale across all NR bands, from low-band to high-band, with configurable raster steps. This allows for precise frequency specification necessary for features like wideband carriers, spectrum sharing, and multi-connectivity, facilitating efficient network deployment and operation in a fragmented spectrum landscape.

Detected Changes Across Releases

from 3GPP Change Requests

Specific changes extracted from the „Change history“ tables of 3GPP specifications (114 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.

Rel-15 2 changes

In Release 15, the NR-ARFCN function was newly introduced to define the absolute radio frequency channel numbering for the 5G New Radio (NR) system. This provided a global scheme for referencing and calculating carrier center frequencies across both Frequency Range 1 (FR1) and Frequency Range 2 (FR2). The introduction standardized the relationship between an NR-ARFCN value and a specific frequency, enabling consistent RF requirements and band definitions as specified in TS 38.104.

  • CR to TS 38.104 on Combined updates from RAN4 #90 This document combines the proposed changes in the following Draft CRs from RAN4 #90: - R4-1900284, "Draft CR on NR PUCCH format2 performance requirements for TS 38.104" - R4-1900763, "Draft CR to TS 38.104: Update of performance requirement numbers for DFT-s-OFDM based PUSCH" - R4-1900876, "Draft CR to TS 38.104: On RX spurious emissions requirement" - R4-1900968, "Draft CR for 38.104: Performance requirements for NR PUCCH format 1" - R4-1901329, "Draft CR to 38.104: Annex C.6 correction" - R4-1901330, "Draft CR to 38.104: Abbreviations addition" - R4-1901387, "Draft CR to TS 38.104 BS demodulation PUCCH format 0 requirements" - R4-1901474, "Draft CR to TS 38.104: Corrections on transmitter co-existence and co-location requirements" - R4-1901483, "Draft CR to TS 38.104: Corrections on general intermodulation requirement" - R4-1902239, "Draft CR to TS 38.104: Addition of missing EIRP/EIS definitions in terminology in clause 3.1" - R4-1902241, "Draft CR to 38.104; clarification of BS power limits" - R4-1902245, "Draft CR to 38.104: Correction to FR2 OTA Interfering signal mean power units" - R4-1902246, "Draft CR to 38.104; Correction to definition of OTA reference sensitivity" - R4-1902260, "draft CR to TS 38.104 - update emissions scaling" - R4-1902338, "Draft CR: Update on FR1 range extension for TS38.104" - R4-1902389, "draftCR for 38.104 on PUSCH requirements with CP-OFDM and FR1" - R4-1902394, "Draft CR to TS 38.104 – PUSCH requirements with CP-OFDM for FR2" - R4-1902396, "CR: Updates to PUCCH formats 3 and 4 performance requirements in TS 38.104" - R4-1902444, "Draft CR to TS 38.104: Editorial CR for BS demodulation requirements" - R4-1902561, "Draft CR for updating PRACH performance requirements in TS38.104" - R4-1902571, "Corrections to 38.104 Delay profile calculation" - R4-1902642, "Draft CR to TS 38.104: Correction on multi-band operation related requirements" TS 38.104CR0019
  • CR to TS 38.104 Combined updates from RAN4 #90bis and RAN4#91 From RAN4 #90bis: - R4-1903105, "Draft CR to TS 38.104: Corrections on terminologies and editorial errors" - R4-1903319, "Draft CR to TS 38.104: removal of unused definition: "minimum EIRP level under extreme condition"" - R4-1903320, "Draft CR to TS 38.104: OSDD information correction" - R4-1903457, "Draft CR to TS 38.104: Removal of FFS for FR2 TDD OFF power level requirement in clause 9.5" - R4-1903499, "Draft CR to 38.104: Correction to unwanted emissions mask for bands n7 and n38" - R4-1903836, "Draft CR to TS 38.104: Correction on description on multi-band operation in section 4.8" - R4-1904024, "Draft CR to TS 38.104 Applicability rules for BS demodulation" - R4-1904234, "draftCR: Correlation matrix for 8Rx in TS 38.104" - R4-1904723, "Draft CR to TS 38.104: Update of performance requirements for DFT-s-OFDM based PUSCH" - R4-1904726, "draftCR for 38.104 on PUSCH requirements with CP-OFDM and FR1" - R4-1904729, "Draft CR on PRACH performance requirements in TS38.104" - R4-1904734, "Draft CR on TS 38.104 Performance requirement for PUCCH format 1" - R4-1904735, "Draft CR on NR PUCCH format2 performance requirements for TS 38.104" - R4-1904739, "Draft CR to TS 38.104 BS demodulation PUCCH format 0 requirements" - R4-1904745, "draftCR: Updates to PUCCH formats 3 and 4 performance requirements in TS 38.104" - R4-1904799, "Draft CR to TS 38.104: FRC update for PUSCH FR1 mapping type B and FR2 DMRS 1+1" - R4-1904816, "Draft CR : Clarification on step 5 and step 6 for delay profiles calculation (38.104)" - R4-1904842, "Draft CR to TS 38.104 BS demodulation CP-OFDM PUSCH FR2 requirements" - R4-1905126, "draft CR to 38.104 for TAE requirements" - R4-1905139, "draft CR to TS 38.104 on EVM measurement (Annex B and C)" - R4-1905140, "Draft CR: editorial correction on FR1 spurious emission requirement in TS38.104" - R4-1905143, "Draft CR for TS 38.104: Addition of NOTE for transmitter intermodulation requirements in certain regions" - R4-1905144, "Draft CR to TS 38.104: FRC reference corrections for the Rx requirements" - R4-1905145, "Draft CR to TS 38.104: Clarification on application of interfering signal offsets for ACS, blocking and intermodulation requirements" - R4-1905148, "Draft CR to TS 38.104: Corrections on out-of-band blocking requirement" From RAN4 #91: - R4-1906002, "Draft CR to 38.104: Subclause 6.7 and 9.8 transmitter intermodulation – correction of interfering signal type" - R4-1906096, "Draft CR to 38.104: Correction of frequency range for OTA spurious emissions" - R4-1906311, "Draft CR to 38.104: Correction on FRC (Annex A)" - R4-1906346, "Removal of n65 in Rel-15 38.104" - R4-1906915, "Draft CR to TS 38.104: Clarification on application of interfering signal offsets for OTA ACS, blocking and intermodulation requirements" - R4-1906918, "Draft CR to TS 38.104: Clarification on type of interfering signal for ACS, in-band blocking and ICS requirements" - R4-1907110, "Draft CR to TS 38.104: correction of the fundamental frequency limit of 2.55GHz for the spurious emissions" - R4-1907246, "Draft CR to TS 38.104: Update of performance requirements for DFT-s-OFDM based PUSCH" - R4-1907249, "Draft CR to TS 38.104: Correction on the terminology in PUSCH FRC tables" - R4-1907252, "Draft CR to TS38.104: Updates of PRACH performance requirements" - R4-1907255, "Draft CR on NR PUCCH format2 performance requirements for TS 38.104" - R4-1907258, "Draft CR on NR UCI on PUSCH performance requirements for TS 38.104" - R4-1907261, "draftCR: Updates to PUCCH formats 3 and 4 performance requirements in TS 38.104" - R4-1907266, "Draft CR on TS 38.104 Performance requirement for PUCCH format 1" - R4-1907267, "Draft CR on TS 38.104 Performance requirement for multi-slot PUCCH format 1" - R4-1907272, "Draft CR to TS 38.104 BS demodulation PUCCH format 0 requirements" - R4-1907275, "Draft CR to TS 38.104 BS demodulation CP-OFDM PUSCH FR2 requirements" - R4-1907277, "draftCR for 38.104 on PUSCH requirements with CP-OFDM and FR1" - R4-1907629, "Draft CR to 38.104: Term “reference signal” replacing by term “ideal signal” in EVM context" - R4-1907634, "Draft CR to 38.104: corrections to the EVM annex" - R4-1907659, "Draft CR to TS 38.104 on Spurious emission Category B in FR2" - R4-1907661, "Draft CR to 38.104 Definition of contiguous transmission bandwidth" - R4-1907662, "Draft CR to 38.104: BS TAE requirements" - R4-1907664, "Draft CR to 38.104: Clarification of interferer RB frequency for narrowband blocking" - R4-1907672, "Draft CR for TS 38.104: Correction on EVM" - R4-1907689, "Correction to CA carrier spacing" TS 38.104CR0029
Rel-16 33 changes

In Release 16, the NR-ARFCN function was updated to support new and wider channel bandwidths for several NR operating bands, including the addition of a 30MHz bandwidth for n50 and a 40MHz bandwidth for n38. The release also introduced wider channel bandwidths in bands n1, n7, n66, n77, and n78, expanding the available RF configurations for base stations. Furthermore, Release 16 defined the introduction of LTE/NR spectrum sharing specifically for the band 48/n48 frequency range.

  • Addition channel bandwidth of 30MHz for n50 in TS 38.104 TS 38.104CR0031
  • CR for TS 38.104: adding wider channel bandwidths in Band n7 TS 38.104CR0037
  • CR for TS 38.104: adding wider channel bandwidths in Band n77/n78 TS 38.104CR0105
  • CR for TS 38.104: Addition channel bandwidth of 40MHz for n38 TS 38.104CR0106
  • Introducing new channel bandwidth for band n28 TS 38.104CR0131
  • CR for TS 38.104: adding wider channel bandwidths for n66 TS 38.104CR0139

+ 27 more changes

Rel-17 20 changes

In Release 17, the NR-ARFCN function was updated to introduce new supported channel bandwidths of 35 MHz and 45 MHz, as detailed in multiple Change Requests to TS 38.104. Additionally, specific band adjustments were made, including a channel raster exception for band n28 and a correction for the channel raster of band n259. These changes expanded the configurability of NR channel bandwidths within existing frequency bands.

  • CR to 37.104: Introduction of requirements for 35 and 45MHz channel bandwidths TS 37.104CR0949
  • CR for TS 37.141: introduction of channel bandwidths 35MHz and 45MHz TS 37.141CR0990
  • Big CR to 38.104 - Additional Channel BW TS 38.104CR0258
  • Big CR to 38.104 - Additional Channel BW TS 38.104CR0291
  • Big CR to TS 38.104: Adding channel BW support in existing NR bands TS 38.104CR0319
  • Big CR to TS 38.104: Adding channel BW support in existing NR bands TS 38.104CR0343

+ 14 more changes

Rel-18 33 changes

In Release 18, the NR-ARFCN function was updated to introduce a new 3 MHz channel bandwidth option and an enhanced channel raster for specific bands. These changes required corresponding updates to synchronization signal raster entries and enabled new NB-IoT in-band operation within this narrower bandwidth. Additionally, the release included corrections and clarifications to channel bandwidths and supported raster points for various bands, such as n109.

  • CR to TS 37.141 - Consideration of NR 3 MHz channel bandwidth TS 37.141CR1068
  • Big CR to TS 38.104: Adding channel BW support in existing NR bands TS 38.104CR0450
  • Big CR to TS 38.104 on introduction of 3 MHz channel bandwidth TS 38.104CR0500
  • Big CR to TS 38.104: Adding channel BW support in existing NR bands TS 38.104CR0512
  • Big CR to TS 38.104: Adding channel BW support in existing NR bands TS 38.104CR0538
  • CR to TS38.104: Introduction of an enhanced channel raster TS 38.104CR0536

+ 27 more changes

Rel-19 26 changes

In Release 19, the primary update for NR-ARFCN was the formal introduction of a new 7 MHz channel bandwidth for NR FR1, alongside corrections and performance criteria for channel bandwidths below 10 MHz, such as 3 MHz. This addition required updates across multiple core specification documents, including TS 38.104, to define the new bandwidth's RF characteristics and ensure proper support within existing NR frequency bands. The release also included specific corrections for reference sensitivity levels and adjacent channel selectivity requirements applicable to these narrower channel bandwidths.

  • CR to TS37.104 Introduction of 7 MHz NR FR1 channel bandwidth TS 37.104CR1028
  • CR to TS 37113 - Introduction of 7 MHz channel BW TS 37.113CR0142
  • CR to TS37.141 Introduction of 7 MHz NR FR1 channel bandwidth TS 37.141CR1098
  • Big CR to TS 38.104: Adding channel BW support in existing NR bands TS 38.104CR0685
  • CR to 38.104 on adding new UL channel bandwidth to band n48 TS 38.104CR0698
  • Running CR to TS 38.104 - Introduction of 7 MHz channel BW TS 38.104CR0725

+ 20 more changes

Explore further

Broader topics and technologies where NR-ARFCN plays a role.

Topics
RRC (Radio Resource Control)Spectrum & CoexistenceLTE / LTE-Advanced5G NR (New Radio)Lawful InterceptUMTS / WCDMA
Technologies
LTE5G

Defining Specifications

3GPP specifications that define or reference NR-ARFCN, with the latest known release. Sourced from the 3GPP document catalog — see methodology.

SpecificationTitleRelease
TS 37.104 vj10 MSR Base Station RF Characteristics Rel-19
TS 37.113 vj00 EMC Requirements for Multi-Standard Radio Base Stations Rel-19
TS 37.141 vj10 RF Test Methods for Multi-Standard Radio Base Stations Rel-19
TS 37.862 vj00 Adding channel bandwidth in existing NR bands Rel-19
TS 38.101 vj31 NR User Equipment Radio Transmissions Rel-19
TS 38.104 vj20 NR Base Station RF Requirements Rel-19
TS 38.108 vj20 NTN NR Satellite Access Node RF Requirements Rel-19
TS 38.113 vj00 NR Base Station EMC Specification Rel-19
TS 38.141 vj20 NR Base Station RF Conformance Testing Part 1 Rel-19
TS 38.174 vj10 NR Integrated Access and Backhaul Radio Spec Rel-19
TS 38.175 vj00 EMC for NR IAB Nodes Rel-19
TS 38.176 vj20 IAB Conformance Testing Specification Rel-19
TS 38.181 vj10 NR Satellite Access Node RF Testing Rel-19
TS 38.521 vj20 NR Physical Layer UE Conformance Testing Rel-19
TS 38.741 vj00 NTN L-/S-band for NR Technical Specification Rel-19
TR 38.786 vi20 Technical Report for NR Sidelink Evolution Rel-18
TR 38.815 vf10 NR Frequency Range 24.25-29.5 GHz Study Rel-15
TS 38.819 vg00 Band n65 for New Radio Technical Report Rel-16
TR 38.847 vh20 NR 47.2-48.2 GHz Frequency Range Rel-17
TR 38.849 vi50 Technical Report Rel-18
TS 38.863 vj10 NR NTN RF and Co-existence Spec Rel-19
TS 38.873 vg00 NR Band n48 Technical Report Rel-16
TS 38.887 vg00 NR Band n259 Specification (39.5-43.5 GHz) Rel-16