Unitac Launches World’s First Tri-Mode Cellular IoT Module for the Global Smart Meter Market

Unitac Technology Limited recently introduced the ML661, a groundbreaking 410/450MHz communication module specifically engineered to elevate connectivity in Smart Meter Gateway (SMGW) and Advanced Metering Infrastructure (AMI) Meter systems—core components of modern energy grids.

Powered by GCT Semiconductor’s 3rd-generation 4G modem chipset GDM7243SL, this dual-core RISC-V module supports LTE, LTE-M, and NB-IoT air interfaces, making it the first and only tri-mode module solution of its kind to address the unique demands of smart metering deployments in a single hardware design.

Tailored for AMI Meters (Electricity, Gas, Water)

The ML661 delivers unmatched reliability in data transmission, a critical requirement for utility operations. Smart meters deployed in residential neighborhoods, rural areas, or industrial zones often face signal challenges due to high-delay spread environments, but the module’s optimized baseband processing ensures consistent communication even in these scenarios. With +23dBm Tx power for LTE bands and +26dBm Tx power for LTE-M/NB-IoT bands (B31/B72/B87), it reliably sends real-time consumption data, usage alerts and device diagnostic information to utility head-end systems(HES)—eliminating data gaps in billing cycles and enabling accurate demand response management.

Support for protocols including TCP, UDP, HTTPS, and LwM2M allows seamless integration with existing meter management platforms. This enables utilities to perform remote firmware updates, troubleshoot device issues, and adjust meter configurations without on-site visits, significantly reducing maintenance costs and improving operational efficiency. The module’s wide operating temperature range (-40℃ to 85℃) and robust design ensure stable performance in diverse environments, from indoor residential meters to outdoor industrial gas/water meters exposed to extreme weather.

Optimized for Smart Meter Gateway (SMGW) Applications

As a robust connectivity hub, the ML661 bridges multiple AMI meters to either private or public networks, supported by its dual-SIM dual-standby (DSDS) feature. This flexibility allows utilities to deploy gateways in areas with limited public network coverage by switching to private networks, ensuring uninterrupted data transmission. Its compact form factor (29mm x 29mm x 2.8mm) fits easily into standard gateway enclosures, while the 80pin LCC + 24pin LGA pin configuration simplifies integration with existing gateway hardware.

With data rates up to 10Mbps in the Downlink and 5Mbps in the Uplink, the module efficiently aggregates data from dozens of connected assets. This enables utilities to monitor real-time energy flows, detect leaks, tampering, or equipment malfunctions promptly, and optimize grid distribution to reduce energy waste. The laser engraving process enhances heat dissipation—critical for gateways operating continuously in enclosed spaces—and ensures product information remains intact over long-term use. Backed by a 15-year lifecycle commitment, the ML661 aligns with the extended operational lifespan of SMGWs, providing utilities with a future-proof investment that avoids frequent replacement costs.

Key Product Advantages

• Multi-Mode Versatility: Supports LTE Cat.1/Cat.1bis, LTE-M, and NB-IoT air interfaces in a single module design, compatible with diverse smart metering connectivity needs.
• Optimized RF Performance: enhanced TX/RX signal processing and interference protection.
• Scalable Hardware: 128Mbit PSRAM, 128Mbit NorFlash, Secure Boot,18 GPIOs, and USB 2.0 for flexible integration.
• Global Compatibility: Three variants (ML661DE/PL/IR) cater to regional band requirements (B31/B72/B87).
• Easy Migration: Minimal effort for existing partners to upgrade from Unitac’s ML660/ML662 series.
• Long-Term Support: 15-year lifecycle commitment and ongoing technical/firmware maintenance.