Description
The Medium Range Base Station (MR) is a standardized network element within the 3GPP Radio Access Network (RAN) architecture. It operates as a transceiver station that communicates with User Equipment (UE) over the air interface, managing radio resource control, scheduling, and connection establishment. The MR base station is characterized by its medium coverage range, which sits between local area (e.g., femtocells) and wide area (e.g., macro cells) deployments, making it suitable for suburban, rural, or specialized coverage scenarios. Its technical specifications encompass transmitter and receiver characteristics, such as output power, frequency bands, modulation schemes, and error vector magnitude (EVM) requirements, which are detailed across numerous 3GPP Technical Specifications (TS) to ensure consistent performance and minimal interference.
Architecturally, an MR base station interfaces with the core network via backhaul links, supporting both control plane and user plane functions. In the context of LTE and 5G NR, it may be implemented as an eNB (E-UTRAN Node B) or gNB (Next Generation Node B), adhering to the functional splits defined by 3GPP. Key internal components include the baseband unit (BBU) for digital signal processing and the remote radio unit (RRU) for radio frequency transmission and reception, though implementations can vary. The MR supports multiple radio access technologies (RATs) as specified, including LTE and NR, and must comply with stringent requirements for spectrum emission, spurious emissions, and receiver sensitivity to maintain network quality.
Its role in the network is pivotal for providing reliable wireless access, enabling services such as voice over LTE (VoLTE), mobile broadband, and IoT connectivity. The MR base station executes critical RAN procedures like cell search and selection, random access, handover, and beamforming (in 5G). It also supports advanced features like carrier aggregation, MIMO (Multiple-Input Multiple-Output), and dual connectivity, depending on the 3GPP release. Management and operation are facilitated through interfaces like the X2 interface (for inter-eNB communication in LTE) or the Xn interface (for inter-gNB communication in 5G), ensuring coordinated mobility and load balancing across the network.
Purpose & Motivation
The Medium Range Base Station (MR) was introduced to address the need for a standardized base station category with a specific coverage range, filling a gap between small cells and macro cells in cellular network deployments. Prior to its standardization, network operators relied on proprietary or less-defined base station types, leading to interoperability challenges and inconsistent performance. By defining MR in 3GPP specifications, it enables vendors to develop compliant equipment that can be seamlessly integrated into multi-vendor networks, ensuring reliable service delivery in medium-range environments such as towns, highways, or industrial areas.
Historically, as cellular networks evolved from 2G to 5G, the diversity of deployment scenarios increased, necessitating base stations with tailored characteristics for different densities and geographies. The MR specification solves problems related to coverage holes, capacity optimization, and cost-effective network expansion. It provides a balanced solution where macro cells might be over-provisioned and small cells insufficient, thus optimizing capital and operational expenditures. The creation of MR was motivated by the industry's move towards more granular and flexible RAN architectures, supporting the growing demand for mobile data and the emergence of new use cases like fixed wireless access.
Furthermore, MR base stations play a crucial role in meeting regulatory requirements for spectrum usage and electromagnetic compatibility. By adhering to standardized technical parameters, they help prevent interference with other radio systems and ensure efficient use of licensed frequency bands. This standardization also facilitates global roaming and equipment certification, contributing to the scalability and reliability of modern cellular networks.
Classification
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (64 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.
Studied in Rel-7, normative work from Rel-15.
In Release 15, the Medium Range (MR) base station function was formally introduced, with specific corrections and updates made to its User Equipment (UE) measurement (UEM) requirements in the core specifications 37.104 and 37.141. Furthermore, technical details for MR base station testing were expanded, including the addition of a 2D Compact Range test procedure for measuring Equivalent Isotropic Radiated Power (EIRP) and Equivalent Isotropic Sensitivity (EIS) as documented in TR 37.843.
- Addition of Annex X for SPID ranges TS 38.300CR0140
- CR to 37.104: Medium Range BS UEM corrections TS 37.104CR0815
- CR to 37.141: Medium Range BS UEM corrections TS 37.141CR0814
- CR to TS 37.145-2: mirror of operating band and frequency range declaration from NR, Rel-15 TS 37.145CR0133
- CR to TR 37.843: Addition of 2D Compact Range. MU, calibration and test procedure for EIRP and EIS. TS 37.843CR0029
- 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
+ 13 more changes
In Release 16, the primary new development for the Medium Range (MR) base station function was the formal introduction of the `n96` frequency band for MR requirements, alongside the enabling of LTE/NR spectrum sharing in the band 48/n48 frequency range. The release also included updates and corrections related to MR operation, such as clarifications for DAPS configuration in MR-DC scenarios and technical adjustments to parameters like the interference level for receiver dynamic range. Furthermore, specifications were refined for co-existence and spurious emissions, solidifying the MR base station class for enhanced network deployments.
- CR to 36.104: Introduction of n96 medium range requirements TS 36.104CR4917
- CR to 37.104: Introduction of n96 medium range requirements TS 37.104CR0915
- Introduction of LTE/NR spectrum sharing in band 48/n48 frequency range TS 38.104CR0220
- Use Case Update for AR/MR Device Type TS 26.928CR0001
- Clarification of DAPS configuration in MR-DC TS 38.300CR0236
- Correction on the value range of BH-LogicalChannelIdentity-Ext TS 38.331CR1955
+ 12 more changes
In Release 17, the MR (Medium Range) function saw specific enhancements for Integrated Access and Backhaul (IAB), including clarifications on the desired IAB-Mobile Terminal (IAB-MT) power spectral density range and corrections for DL TX power adjustment range extension. Furthermore, the release introduced corrections for further MR-DC (Multi-Radio Dual Connectivity) enhancements and its release procedures, specifically concerning the BAP entity. It also extended the in-band blocking requirements for multi-band Base Stations across multiple technical specifications.
- Clarification on desired IAB-MT PSD range TS 38.321CR1538
- Correction to 38.321 on Integrated Access and Backhaul for NR Rel-17 concerning DL TX power adjustment range extension TS 38.321CR1540
- Corrections for further MR-DC enhancements TS 38.331CR3459
- Corrections for further MR-DC enhancements TS 38.331CR3563
- Addition of extended number range for NS value TS 38.331CR3900
- CR to 36.104: In-band blocking for multi-band Base Stations TS 36.104CR4940
+ 7 more changes
In Release 18, key updates for the Medium Range (MR) function were introduced. The specifications were corrected to update and clarify the applicable frequency range 2 (FR2) for Integrated Access and Backhaul (IAB) node requirements and performance. Furthermore, a specific correction was made to the downlink data to uplink acknowledgement (DL-DataToUL-ACK) range for Air-to-Ground (ATG) communications.
- (NR_FR1_lessthan_5MHz_BW-Core) CR to TS38.104 Add NB-IoT RB power dynamic range for 3MHz TS 38.104CR0681
- Clarification on supporting two logical DUs and connecting via stationary IAB node TS 38.300CR0853
- Correction of the range of DL-DataToUL-ACK for ATG TS 38.331CR4857
- (LTE_LAA-Perf) CR to TS 36.141 on correction of base station output power for Band 46 TS 36.141CR1383
- (NR_newRAT-Core) CR for Total power dynamic range (TPDR) TS 38.104CR0611
- CR to correct FR2 range in IAB specifiaiton TS 38.174CR0067
+ 4 more changes
In Release 19, the new specifications for Medium Range (MR) Base Stations introduced key performance requirements for operation in new frequency bands. This included defining the BS antenna pattern and spectral mask for the 14800 to 15350 MHz range, and establishing BS blocking response and spurious emissions requirements for the 4400 to 4800 MHz range. Furthermore, a correction was made to the NB-IoT Medium Range Base Station's Out-of-Band Unwanted Emissions (OBUE) requirements to ensure accuracy for this release.
- (FS_NR_IMT_4400_7125_14800MHz) CR to TR 38.922 on BS antenna pattern for 14800 to 15350 MHz frequency range TS 38.922CR0004
- (FS_NR_IMT_4400_7125_14800MHz) CR to TR 38.922 on BS blocking response performance requirements for 4400 to 4800 MHz frequency range TS 38.922CR0005
- (FS_NR_IMT_4400_7125_14800MHz) CR to TR 38.922 on BS spurious emissions for 4400 to 4800 MHz frequency range and spectral mask for 14800 to 15350 MHz frequency range TS 38.922CR0010
- (NB_IOT-Core) CR for TS36104 to correct NB-IoT Medium Range BS OBUE requirements for R19 TS 36.104CR5013
Explore further
Broader topics and technologies where MR plays a role.
Defining Specifications
3GPP specifications that define or reference MR, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 22.156 vj10 | Mobile Metaverse Services | Rel-19 |
| TR 22.978 vj00 | Feasibility of All-IP Network (AIPN) in 3GPP | Rel-19 |
| TS 25.104 vj00 | UTRA FDD Base Station RF Characteristics | Rel-19 |
| TS 25.141 vj00 | UTRA FDD Base Station RF Conformance Testing | Rel-19 |
| TS 26.119 vj00 | XR Media Capabilities for AR Devices | Rel-19 |
| TS 26.506 vj20 | Real-Time Media Communication Architecture for 5G | Rel-19 |
| TR 26.812 vi10 | Technical Report | Rel-18 |
| TR 26.857 vi00 | Technical Report on Media Service Enablers | Rel-18 |
| TR 26.928 vj00 | Study on eXtended Reality (XR) in 5G | Rel-19 |
| TR 26.998 vj00 | 5G AR/MR Glasses Integration Study | Rel-19 |
| TS 29.079 vj00 | Optimal Media Routeing (OMR) Procedures | Rel-19 |
| TS 33.849 ve00 | 3GPP Privacy Principles and Guidelines | Rel-14 |
| TS 36.104 vj10 | Base Station (BS) radio transmission and reception | Rel-19 |
| TS 36.141 vj00 | E-UTRA BS Conformance Testing | Rel-19 |
| TS 36.755 vf00 | US 600 MHz LTE Band 71 Technical Report | Rel-15 |
| TS 36.761 vf00 | Extended-Band 12 Study Report | Rel-15 |
| TS 37.104 vj10 | MSR Base Station RF Characteristics | Rel-19 |
| TS 37.141 vj10 | RF Test Methods for Multi-Standard Radio Base Stations | Rel-19 |
| TS 37.145 vj10 | AAS Base Station Conducted Conformance Testing | Rel-19 |
| TS 37.809 vb00 | E-UTRA & MSR BS Class Requirements | Rel-11 |
| TS 37.814 vc00 | L-band Supplemental Downlink for UTRA/E-UTRA | Rel-12 |
| TS 37.842 vd30 | BS RF Requirements for Active Antenna Systems | Rel-13 |
| TR 37.843 vf70 | AAS BS Radiated RF Requirement Background | Rel-15 |
| TR 37.941 vj20 | RF Conformance Testing Background for Radiated BS Requirements | 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 38.106 vj20 | NR Repeater Radio Transmission and Reception | Rel-19 |
| TS 38.115 vj20 | NR Repeater RF Conformance Testing Part 1 | 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 38.176 vj20 | IAB Conformance Testing Specification | Rel-19 |
| TS 38.300 vj00 | NG-RAN Overall Description | Rel-19 |
| TS 38.304 vj00 | UE RRC_IDLE and RRC_INACTIVE Procedures | Rel-19 |
| TS 38.321 vj00 | NR MAC Protocol Specification | Rel-19 |
| TS 38.331 vj00 | NR Radio Resource Control (RRC) Protocol Specification | Rel-19 |
| TS 38.774 vj00 | Rel-19 LP-WUS/WUR RF Requirements TR | Rel-19 |
| TS 38.809 vg60 | IAB Radio Transmission & Reception Background | Rel-16 |
| TS 38.817 | 3GPP TR 38.817 | Rel-7 |
| TR 38.820 vg10 | NR; 7-24 GHz Frequency Range Study | Rel-16 |
| TR 38.838 vh00 | Study on XR Evaluations for NR | Rel-17 |
| TR 38.869 vi00 | Study on low-power wake up signal and receiver for NR | Rel-18 |
| TR 38.892 vi00 | Technical Report | Rel-18 |
| TR 38.921 vj00 | IMT Parameters Study for 6.4-7.1 & 10-10.5 GHz | Rel-19 |
| TR 38.922 vj20 | Study on IMT Parameters for NR in Higher Bands | Rel-19 |
| TS 51.021 vj00 | RF test methods and conformance requirements for GSM BSS | Rel-19 |