RDF-USB — USB to 868MHz RF Communication Bridge

Break free from Wi-Fi congestion and line-of-sight constraints with native 868MHz Sub-1GHz RF control directly from your USB port.

The RDF-USB bridge delivers plug-and-play Sub-1GHz RF connectivity powered by the state-of-the-art Texas Instruments CC1312PSIP System-in-Package. Instantly equip your Windows PC, Raspberry Pi, Industrial Linux Server, or OPC UA Gateway with powerful, long-range wireless data exchange.

High-Power Output, Hardware Expansion & Protocols

● Onboard Hardware I2C Interface Header: Features a dedicated I2C port directly on the PCB. All external I2C sensors (temperature, humidity, air quality, barometric pressure, IMUs, accelerometers, etc.) can be tied directly to this device, turning the RDF-USB into a standalone sensor-logging node without requiring external microcontroller boards.

● +20 dBm Output Power (Integrated PA): With an onboard power amplifier, the RDF-USB drives up to +20 dBm output power for extreme link margins, punching through dense industrial walls, concrete floors, and long outdoor distances.

● Point-to-Point (P2P) Communication: Ideal for direct node-to-node cable replacement, remote serial telemetry, and instant field data loggers using 2-GFSK/4-GFSK custom RF protocols.

● TI 15.4-Stack Star Topology: Deploy robust, IEEE 802.15.4-based star networks connecting hundreds of edge sensors to a central RDF-USB gateway. Supports frequency hopping, packet acknowledgments, and AES encryption.

● Broad Industrial Standard Support:

• Wi-SUN®: Seamless mesh networking for smart utility grids and smart cities.
• Wireless M-Bus: Native support for European EN 13757-4 smart metering systems (Gas, Water, Electricity).
• mioty®: Ultra-reliable LPWAN technology engineered for challenging massive-IoT industrial environments.
• 6LoWPAN: Native IPv6 packets over Sub-1GHz radio for direct cloud-to-device IP routing.

Technical Specifications

• Core MCU: TI CC1312PSIP (48MHz Arm® Cortex®-M4F, 352KB Flash, 80KB SRAM)
• Sensor Bus: Onboard I2C Expansion Port (compatible with all standard I2C sensors)
• RF Power Output: Adjustable up to +20 dBm (Integrated PA)
• Receiver Sensitivity: Down to -119 dBm (2.5 kbps Long Range Mode)
• Operating Frequency: 863 MHz – 870 MHz (European SRD / ISM Band)
• USB Interface: Onboard USB-to-UART Bridge with Type-C connector
• Antenna Connection: Onboard u.FL / IPEX connector with included flexible dipole antenna
• Security Engine: Hardware AES-128/256, SHA-2, TRNG, and ECC accelerators
• Status Indicators: Power (PWR), Receive (RX), and Transmit (TX) LEDs

Expanded Application Scenarios

Implementation Example (Python Serial RF & Sensor Bridge)

Send and receive 868MHz data frames alongside local I2C sensor telemetry using standard PySerial interface on Linux or Windows.

import serial
import time

# ===== CONFIGURATION =====
PORT = "/dev/ttyUSB0"  # Windows: "COM4"
BAUDRATE = 115200

def main():
    try:
        with serial.Serial(PORT, BAUDRATE, timeout=1) as rf_bridge:
            print(f"Opened RDF-USB Bridge on {PORT} at {BAUDRATE} baud.")
            
            # Broadcast a test packet with onboard/external I2C sensor payload
            payload = "PING:NODE_01:I2C_TEMP=24.5C:STATUS_OK\n"
            rf_bridge.write(payload.encode('utf-8'))
            print(f"Transmitted (+20dBm RF): {payload.strip()}")
            
            while True:
                if rf_bridge.in_waiting > 0:
                    incoming = rf_bridge.readline().decode('utf-8', errors='ignore').strip()
                    print(f"[RF RX] Received Frame: {incoming}")
                time.sleep(0.1)
                
    except Exception as e:
        print(f"Error accessing RDF-USB interface: {e}")

if __name__ == "__main__":
    main()

Documentation & Resources