Wireless RF Modules and dongles for IoT | Coral RF

Dual-Frequency Design: One module operates on two distinct Sub-1GHz bands simultaneously (select one pair per model). Learn more about our dual‑band technology.
Chipset: TI CC1125 + Power Amplifier (PA) + TCXO
Output Power: +27 dBm (~500 mW)
Sensitivity: -126 dBm
Frequency Pairs (Choose One):
- Option A: 169 MHz + 868/915 MHz
- Option B: 433 MHz + 868/915 MHz
Range: Up to 6000 m (6 km)
Interface: SPI Control – SPI programming guide
Protocol Support: Narrowband FSK, WMBUS (Wireless M-Bus), Arduino compatible
Size: 41 x 30 x 3 mm – mechanical drawing

⚡ Key Specifications

Parameter	Specification
Supply Voltage	2.0V - 3.6V
TX Current	~500 mA (@ +27dBm)
RX Current	~35 mA
Data Rate	0 - 200 kbps (Narrowband)
Modulation	2-FSK, 4-FSK (Narrowband)
Antenna	RF Pad + IPEX Connector
Operating Temp	-40°C to +80°C

🎯 Why Choose a Dual-Frequency Module?

Single SKU for Multi-Region Products: Build one product that works in regions with different primary ISM bands (e.g., 169MHz in EU for metering, 868MHz for general IoT).
Backup/Redundant Communication: Implement frequency hopping or fallback to a secondary band if the primary band experiences interference.
Multi-Protocol Gateway: Act as a gateway that communicates with different device networks operating on different standard frequencies.
Simplified Inventory: Reduce the number of module variants you need to stock and manage.

🏭 Target Applications

Advanced Metering Infrastructure (AMI): Smart meters that must communicate on both utility (169MHz) and consumer (868MHz) networks.
Multi-Protocol IoT Gateways: Hubs that bridge devices using different frequency standards.
Global Asset Trackers: Devices that need to switch frequencies based on geographic location.
Professional WMBUS Systems: For building automation and utility metering requiring robust, multi-band communication.

🔧 Development Notes

Frequency Control: The two frequencies are not used simultaneously for full-duplex. The host MCU must control the CC1125 via SPI to switch between the two pre-configured frequency settings.
Antenna Design: Requires a single antenna that is broadly tuned to cover both frequency bands (e.g., 169MHz and 868MHz) with reasonable efficiency, or a switched/tunable antenna system for optimal performance on each band.

🛒 Model Selection Guide

Model	Frequency Pair	Primary Application Scenario	Ordering Info
N520BS-A	169 MHz & 868/915 MHz	EU Smart Metering + IoT. A meter that reports via 169MHz WMBUS to the utility and can also use 868MHz for local diagnostics or consumer data.	Order N520BS‑A
N520BS-B	433 MHz & 868/915 MHz	Global Multi-Band Sensor. A sensor that works in 433MHz regions (Asia) and 868/915MHz regions (EU/US) without hardware change.	Order N520BS‑B

⚠️ Important Considerations

Antenna Challenge: Designing a single antenna to perform well on two widely separated bands (e.g., 169MHz and 868MHz) is non-trivial and may involve trade-offs in efficiency. We offer certified antenna reference designs to simplify this.
Regulatory Compliance: The module must be certified for operation on both frequency bands in the target regions, which can be complex.
Firmware Complexity: Your firmware must correctly manage the timing and configuration for switching between the two frequency modes. Access our example code.

🚀 Is This Module Right For You?
Choose the N520BS if:

Your product must operate on two different, predefined Sub-1GHz bands.
You want to reduce SKU count for a global product line.
You are building a professional gateway or meter with multi-network capability.

Consider a standard single-band module if:

Your application only ever uses one frequency.
You require the absolute maximum performance (range, efficiency) on a single band.

The N520BS solves the complex problem of dual-band operation by integrating it into a single, robust module. It's a strategic choice for advanced, flexible wireless system design.