RFD900A 915MHz Long-Range Radio Telemetry Data Link - 1W Adjustable Power, 40+ km Range, Dual Antenna, LNA and SAW Receiver for UAV and Wireless RF Data Transmission
The RFD900A is a high-performance 915MHz wireless data transmission module designed for long-range UAV telemetry, ground station communication, and point-to-point RF data link applications where the range limitations of standard 100mW and 500mW telemetry radios are insufficient for the operational requirements of the platform. Operating across the 902-928MHz ISM frequency band, the RFD900A delivers a maximum transmit power of 1W (30dBm) with adjustable output levels for regulatory compliance and link budget optimisation, and achieves outdoor line-of-sight communication distances exceeding 40 kilometres under optimal antenna and low-data-rate conditions, placing it in a substantially higher range class than the 3DR telemetry radio family it is designed to complement and extend. The receiver front-end incorporates a pre-installed high-sensitivity Low Noise Amplifier and Surface Acoustic Wave filter circuit, improving receiver sensitivity and adjacent-channel rejection to sustain reliable data link performance at the extreme range margins where the transmit power advantage of the RFD900A is most operationally relevant.
A significant practical feature of the RFD900A is the elimination of the transmit-receive hardware distinction common in paired telemetry radio kits. Each RFD900A module integrates a USB serial port chip alongside the UART interface, with automatic USB-to-UART switching that gives priority to the USB connection when both interfaces are simultaneously present. This allows any individual RFD900A unit to function as either the air-side or ground-side radio in a paired link without hardware modification, simplifying spares management and field configuration in operational UAV deployments. Dual antenna interfaces on each module support antenna diversity and differentiated antenna configurations, allowing omnidirectional and directional antennas to be combined on a single module for optimised link performance across varying flight geometries. The onboard temperature monitoring function automatically adjusts the duty cycle in response to module temperature, preventing thermal overload during sustained high-power transmission without requiring manual power management intervention. AT commands support local module configuration, and RT commands enable remote configuration of the paired air-side module from the ground station across the live data link.
Key Features
- Frequency Band: 902-928MHz ISM band for long-range UAV telemetry and point-to-point RF data link in 915MHz-permitted regions
- Maximum Transmit Power: 1W (30dBm) adjustable output for link budget optimisation and regulatory compliance across different operational environments
- Long-Range Performance: Outdoor line-of-sight communication range exceeding 40 kilometres under optimal antenna and low-data-rate conditions
- Low Noise Amplifier: Pre-installed greater than 20dB gain LNA on the transmit circuit for improved signal-to-noise ratio at extended range
- SAW Filter: Pre-installed Surface Acoustic Wave filter on the receiver circuit for improved adjacent-channel rejection and receiver selectivity
- No Air-Ground Hardware Distinction: Each module functions as either air-side or ground-side radio without hardware modification, simplifying spares and field configuration
- Integrated USB Serial Port Chip: Onboard USB serial chip with automatic USB-to-UART interface switching, USB socket priority when both interfaces are present
- Dual Antenna Interface: 2 antenna ports per module supporting antenna diversity and differentiated omnidirectional-plus-directional antenna configurations
- Air Data Rate: Up to 250kbps maximum air data rate for high-throughput telemetry and data transfer applications
- Adjustable Transmit Power: Software-configurable output level for regulatory compliance and co-existence with other 915MHz band users
- Temperature Monitoring: Onboard module temperature monitoring with automatic duty cycle adjustment to prevent overheating during sustained high-power transmission
- AT Command Configuration: Local AT command radio configuration for power, data rate, and link parameters
- RT Command Configuration: Remote RT command configuration of the paired air-side module from the ground station across the live data link
- Wide Operating Temperature: -40°C to 85°C operating range for reliable deployment across airborne, outdoor, and industrial thermal environments
- Compact and Lightweight: 23g module weight for minimal UAV payload penalty on fixed-wing and multirotor air platforms
Applications
- Long-range UAV and fixed-wing aircraft telemetry requiring beyond-standard-range data links exceeding the 1-3 kilometre ceiling of standard 500mW telemetry radios
- APM, PX4, Pixhawk, and ArduPilot flight controller ground station communication over extended operational ranges up to 40+ kilometres
- Point-to-point wireless RF data link for remote sensor stations, environmental monitoring nodes, and field data acquisition systems
- BVLOS (Beyond Visual Line of Sight) UAV operations requiring a long-range, high-reliability 915MHz data link with adjustable power output
- Dual-antenna diversity configurations combining omnidirectional and directional antennas for optimised link geometry across variable UAV flight paths
- High-altitude and long-endurance fixed-wing UAV platforms requiring sustained 1W telemetry output with automatic thermal duty cycle management
