Description
A Multi-Standard Radio (MSR) Base Station is a advanced radio access node defined in 3GPP specifications that supports the operation of two or more 3GPP radio access technologies (RATs) within a single station. The supported RATs typically include GSM/EDGE (GERAN), UMTS (UTRAN), and LTE (E-UTRAN), and potentially 5G NR in later implementations, all operating within defined frequency bands. The key architectural principle of an MSR BS is the sharing of common radio hardware components—such as power amplifiers, filters, transceivers, and antennas—across the different RATs. This is achieved through software-defined radio (SDR) principles and advanced baseband processing. The station contains multiple baseband processing units (for each RAT) that feed into a common radio unit. This unit uses wideband RF components capable of covering the aggregated bandwidth of all active carriers. Dynamic spectrum sharing is a critical capability, where the MSR BS can allocate radio resources (frequency blocks, power) between the co-existing RATs based on traffic demand and operator policies. The MSR BS must meet strict 3GPP performance requirements (specified in TS 37.1xx series) for each supported RAT independently, ensuring that the shared operation does not degrade the performance of any individual technology. It interfaces with respective core networks (e.g., MSC for GSM/UMTS, MME for LTE) via standard interfaces (Iu, S1). Management is unified, allowing operators to configure and monitor all RATs through a single management system.
Purpose & Motivation
The MSR Base Station was developed to address the practical and economic challenges of network evolution and multi-technology coexistence. As mobile operators deployed successive generations of technology (2G, 3G, 4G), they often faced spectrum fragmentation, site congestion, and escalating costs from maintaining separate base station cabinets, antennas, and backhaul for each RAT. The MSR concept, introduced in 3GPP Rel-9, provided a standardized solution for a single hardware platform that could support multiple standards. This solved the problem of inefficient spectrum use and high capital/operational expenditure (CapEx/OpEx) associated with parallel network deployments. It enabled smoother technology migration, allowing operators to re-farm spectrum from older technologies (like GSM) to newer ones (like LTE) dynamically without needing to physically replace hardware. The creation of MSR was motivated by the industry's need for future-proof, scalable infrastructure that could handle the growing complexity of radio access networks while simplifying site acquisition, power consumption, and maintenance.
Classification
Release Timeline
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (36 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.
In Release 15, the Multi-Standard Radio (MSR) base station specifications were extended to introduce and define the operation of 5G New Radio (NR) alongside legacy technologies. This included adding NR-specific core requirements for electromagnetic compatibility (EMC) and updating blocking and transmitter exclusion band requirements for MSR/NR operation. The release also provided corrections and enhancements for MSR BS supporting NR in non-contiguous spectrum operations.
- Introduction of NR operation in MSR specification 37.104 TS 37.104CR0816
- CR to TS 37.113 (MSR EMC): NR EMC Core Requrements updates TS 37.113CR0082
- CR to TS 37.113: introduction of the NR to MSR EMC specification TS 37.113CR0092
- Introduction of NR operation in MSR specification 37.141 TS 37.141CR0831
- Corrections to NR operation in MSR specification 37.104 TS 37.104CR0825
- Corrections to NR operation in MSR specification 37.104 TS 37.104CR0831
+ 5 more changes
In Release 16, the enhancements for the Multi-Standard Radio (MSR) base station primarily focused on refining blocking requirements and correcting the transmitter transient period specification. The changes, applied to both the conformance testing (TS 37.141) and the base station requirements (TS 37.104) specifications, aimed to ensure more precise and consistent interference immunity measurements for MSR equipment operating across multiple bands and standards. These updates provided clearer definitions for the blocking test scenarios and the measurement periods involved.
- CR to TS 37.104 – Blocking requirement for MSR TS 37.104CR0838
- CR to TS 37.104: Correction to Tx transient period of MSR TS 37.104CR0890
- CR to 37.104 on MSR Blocking correction TS 37.104CR0919
- CR to TS 37.141 – Blocking requirement for MSR TS 37.141CR0849
- CR to 37.141 on MSR Blocking correction TS 37.141CR0958
In Release 17, the Multi-Standard Radio (MSR) base station specifications were updated with corrections and clarifications to the supported New Radio (NR) operating bands. The changes focused on refining the technical test configurations and performance criteria for MSR base stations to ensure accurate multi-standard operation. Specifically, the modifications addressed the proper identification of NR bands within the MSR framework and updated the corresponding test procedures.
In Release 18, the MSR function saw clarifications and updates to its RF and performance testing specifications, particularly for multi-band operation and spurious receiver protection. The work included corrections and new definitions for test signals, interference bandwidth, and power allocation in non-contiguous (NC) operation scenarios during conformance testing. These changes were applied across several technical specifications, including TS 37.104, TS 37.105, TS 37.141, and TS 37.145-2.
- (MB_MSR_RF) CR to 37.104: clarification on requirements for BS capable of multi-band operation TS 37.104CR1011
- (TEI17) CR to TS 37.104 - BS spurious receiver protection note [MSR_BSRF_RX] TS 37.104CR1018
- (TEI17) CR to TS 37.105 - BS spurious receiver protection note [MSR_BSRF_RX] TS 37.105CR0292
- [MSR_NC-Perf] CR to TS 37.141 NR with Multipath fading of GSM for MSR BS TS 37.141CR1049
- [MSR_NC-Perf] CR to TS 37.141 with correction to interference signal bandwidth for MSR BS TS 37.141CR1053
- [MSR_NC-Perf] CR to TS 37.141 with the rated output power definition of the test signal for MSR BS TS 37.141CR1056
+ 5 more changes
In Release 19, the primary update for the Multi-Standard Radio (MSR) base station was the complete removal of UTRA TDD from the relevant MSR specifications. This change was implemented across multiple technical documents covering requirements, conformance testing, and base station performance. The release also introduced a new test procedure for additional transmitter intermodulation for MSR operation.
- (RInImp9-Rfmulti,TEI17) CR to 37.104: Removal of UTRA TDD from MSR BS specifications TS 37.104CR1036
- (AAS_BS_LTE_UTRA-Core,TEI17) CR to 37.105: Removal of UTRA TDD from MSR BS specifications TS 37.105CR0316
- (RInImp9-Rfmulti,TEI17) CR to 37.141: Removal of UTRA TDD from MSR BS specifications TS 37.141CR1106
- (AAS_BS_LTE_UTRA,TEI17) CR to 37.145-2: Removal of UTRA TDD from MSR BS specifications TS 37.145CR0414
- (AASenh_BS_LTE_UTRA-Perf) CR to 37.145-2: test procedure for additional transmitter intermodulation for MSR operation TS 37.145CR0403
Explore further
Broader topics and technologies where MSR plays a role.
Defining Specifications
3GPP specifications that define or reference MSR, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TR 21.905 vj00 | 3GPP Technical Terms and Definitions | Rel-19 |
| TS 36.744 ve00 | CBRS 3.5GHz Band Specification for US | Rel-14 |
| 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 36.790 vf00 | LAA/eLAA for CBRS 3.5GHz Band in US | Rel-15 |
| TS 36.858 ve00 | LTE 2.6 GHz SDL Band Technical Report | Rel-14 |
| TS 37.104 vj10 | MSR Base Station RF Characteristics | Rel-19 |
| TS 37.105 vj10 | AAS Base Station Transmission & Reception Requirements | Rel-19 |
| TS 37.113 vj00 | EMC Requirements for Multi-Standard Radio Base Stations | Rel-19 |
| TS 37.114 vj00 | EMC for Active Antenna System Base Stations | 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 37.802 va10 | MSR BS RF Requirements for Non-Contiguous Spectrum | Rel-10 |
| TS 37.808 vc00 | PIM Handling for Base Stations Study | Rel-12 |
| TS 37.812 vb30 | Multi-band Multi-standard Radio BS Requirements | Rel-11 |
| TS 37.814 vc00 | L-band Supplemental Downlink for UTRA/E-UTRA | Rel-12 |
| TR 37.900 vj00 | Multi-Standard Radio (MSR) Base Station Requirements | Rel-19 |
| TS 38.819 vg00 | Band n65 for New Radio Technical Report | Rel-16 |
| TR 38.892 vi00 | Technical Report | Rel-18 |
