I recently started an open-hardware project based on my RF work for the past several years. Although I was targeting challenging real-time data collection in a tree-fruit orchard envrionment, UAV telemetry seems like a very good match for the design due to the inherent attributes of Low-latency and High reliability. This modem is very similar to the performance characteristics of something like the original MHX910 from Microhard Systems. Let me know what you think.
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Project Development Site For Valhalla Wireless OpenFHSS. OpenFHSS is a community-based effort that includes schematic, eagle design files, BOM, gerbers, and firmware for a 902-928MHz ISM, 50-channel, FHSS frequency hopping spread spectrum modem.
- High Performance, Long-Range Frequency Hopping Spread Spectrum Modem
- Synchronous, Multi-Hop Repeater Chains
- Ethernet Bridge Mode
- Automatic, over-the-air firmware updates. Master updates all slaves simultaneously
- 4uA MCU initiated sleep current
- 2ppm stability for frequency and system timing reference.
- Industrial quality enclosure, connectors
- Real-Time Data Collection System with user defined scripts
- LM3S6965 32-Bit Stellaris ARM-core MCU, CC1101 transceiver, CC1190 LNA/PA
- Highly immune to multipath fading, interference
- 5mS Channel Dwell Time
- -107dBm sensitivity, 27.1dBm output power enables communications range in tens of kilometers. Depending on installation, ranges of >50km are easy to achieve
- Applications include battery-powered data collection, Low-Latency Telemetry Links (UAVs), long-range internet communications. Quality Skype phone calls have been achieved with point-to-points links.
- 230 kbps RF Data Rate
- very low phase noise performance (see emc plots in images/emc_testing)