Today we declared beta for our newest networking stack for LoRa, DASH7 XR Mode. After months of hard work to improve the wireless range of Semtech’s LoRa LPWAN radio, we are pleased with the results.
XR Mode was initially a response to customer asking why gateways and endpoints deployed near ground level achieve a wireless range or distance that is less — far less — than what is advertised by certain entities promoting LoRa or LoRaWAN who employing “ideal” range testing conditions. For customers deploying LoRa for mobile use cases like asset tracking, signal propagation can be highly variable and “range” becomes a subjective term. Unlike LTE radios that blast at high wattage, the low power output of LoRa means negotiating RF-unfriendly environments over long distances is a challenge, particularly at ground level. So optimizing range and Quality of Service (QoS) for ground level is where we began, but the benefits of XR Mode apply to LoRa radios deployed at any altitude.
Major takeaways for XR Mode:
- XR Mode offers a robust 23 dB boost over DASH7 LAN mode for LoRa. See our presentation below for more details.
- XR Mode utilizes LDPC error correction, replacing the Hamming codes used by the LoRa radio. XR Mode implements LDPC on a 2-way basis, not just from the endpoint to the gateway, but vice-versa or on a P2P basis. Even the acks are encoded and decoded.
- XR Mode utilizes shorter packet sizes and lower data rates. Currently we are testing at 1.1 kbps but lower data rates are certainly possible depending on your battery life needs.
- XR Mode is now the longest range, networking stack available for battery powered LoRa devices today. In terms of real-world range improvements, we saw suburban ground level (2 meter antenna height for gateway and 1 meter antenna height for endpoint) range improve by more than 3x and when gateway antennas were raised to 5 meters, by 5x. At more extreme (i.e. cellular industry) gateway heights (e.g. 3,849 feet atop Mount Diablo in Danville, CA) we achieved range of 36 miles to an endpoint on the ground north of Stockton, CA using a simple dipole antenna.
- XR Mode preserves key features like GNSS/GPS-based location while continuing to preserve multi-year battery life.
- Devices running XR Mode are now LoRa devices 22 times (twenty-two) more battery efficient than comparable LoRaWAN devices.
And we expect this performance to only improve. Check out our deck:
I will be posting more about XR Mode and related topics, but if you are interested in giving XR Mode a test drive, our XR Mode UDP demo for the ST Micro Discovery Kit (SX1276) with external dipole is available to a limited number of participants in a private beta program. You sign up here.