Regulatory Update: Technical Specification for Cellular Mobile Terminals (IMDA TS CMT)
The Info-communications Media Development Authority (IMDA) of Singapore has issued an updated technical specification (Issue 1 Revision 4) regarding the minimum technical requirements for Cellular Mobile Terminals (CMTs). This document outlines essential changes to certification standards, frequency allocations, and mandatory device configurations for manufacturers and type approval applicants.
Summary of Proposed Changes and Standards
The revised specification introduces several updates to align with international standards and local network requirements:
2G Connectivity Restriction: Devices must now have 2G connectivity disabled in the factory default configuration. Connection to 2G networks must require deliberate user action (e.g., navigating a settings menu).
Emergency Cell Broadcast (CBS): Mandated support for "SG Alert" and "Test Alert" notifications. This includes specific requirements for audio attention signals, vibration cadences, and the ability to display notifications without user interaction.
VoLTE Requirements: CMT devices designed for voice calling must support Voice-Over-LTE (VoLTE) technology and have it enabled by default.
5G NR Enhancements: Incorporation of testing parameters for 5G FR1 devices with Reduced Capability (RedCap) functionality and interworking operations between 5G FR1 and FR2.
Safety Standards Update: Inclusion of IEC 60086-4 for lithium battery safety and updated RF EMF exposure assessment procedures.
Impact on Manufacturers and Stakeholders
Manufacturers must adapt their production and testing protocols to ensure compliance with the following:
Factory Configuration: Software must be pre-configured to disable 2G and enable VoLTE.
Labeling and Documentation: Suppliers must provide Specific Absorption Rate (SAR) or power density information in the user guide or equipment package.
Safety Testing: Equipment must comply with IEC 62368-1 (Minimum Edition No. 2) and specific lithium battery standards (UL 1642, IEC 62133, or IEC 60086-4).
Identification: Each CMT must be allocated a unique IMEI or PEI, and manufacturers must implement security measures to prevent duplication or unauthorized removal of these identifiers.
Technical Parameters and Permitted Radio Bands
The specification defines the operating frequency bands for E-UTRAN and 5G NR (New Radio) as follows:
Low and Mid Bands: Includes Bands 1 (n1), 3 (n3), 7 (n7), 8 (n8), 26 (n26), 28 (n28), 38 (n38), and 40 (n40).
5G Sub-6GHz: Bands n77 (3300 MHz – 4200 MHz) and n78 (3300 MHz – 3800 MHz).
5G mmWave: High-frequency bands n257, n258, and n261 (ranging from 24250 MHz to 29500 MHz).
Compliance Deadlines
Stakeholders should take note of the following transition period regarding RF EMF safety standards:
Standard Transition: Previous standards (IEC/EN 62209-1 and IEC/EN 62209-2) will no longer be accepted by IMDA for compliance after October 1, 2025.
Replacement Standard: Manufacturers must utilize IEC/EN 62209-1528:2020 for compliance assessments from the cutoff date onward.
Testing and Certification Procedures
Conformance testing must be performed against specific international standards depending on the technology:
4G LTE: ETSI EN 301 908-13 and associated radiated emissions standards.
5G NR (FR1 & FR2): ETSI EN 301 908-25, ETSI TS 138 521-1, and ETSI TS 138 521-2.
EMC Requirements: Compliance with ETSI EN 301 489-1 and ETSI EN 301 489-52 is required for emission and immunity measurements.
