MultiNav Pro+ BLE - reliable link budget math for a 50km deployment?

John Jones•July 14, 2026

Hey everyone, John Jones from the hardware side here. We're in the middle of scoping out a deployment where we need to cover a pretty wide open area - think flat terrain, minimal obstructions, basically ideal RF conditions on paper. The 50km spec on the BLE module is obviously what caught our attention but I'm trying to work backwards from that to actually understand the link budget assumptions baked into that number. Like what TX power output are we working with, and what's the assumed receiver sensitivity on the other end? Trying to figure out if we need to account for any additional gain in the system or if the front-end handles most of that headroom already.

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Adam•July 14, 2026

@John Jones good question — and flat open terrain is basically the best case scenario for that 50km figure, so you're already starting from the right place.

I want to be straight with you though: the specific TX power and receiver sensitivity numbers that go into the link budget math aren't something I can give you off the top of my head with confidence — that level of detail lives in the hardware documentation and firmware specs rather than something I'd want to quote from memory and have you build a deployment around. The STM32WB07 at the core of the module has published sensitivity figures you can pull from the ST datasheet, and the external amplifier stage is where a lot of the magic happens on top of that baseline.

What I'd actually recommend is jumping into the GitHub repo (github.com/RFOXiA/MultiNav-Pro-Long-Range-BLE-Module-Firmware-STM32WB07) — there's firmware-level detail in there that should help, and honestly Moamen is pretty active around the Dev Hub and would be the right person to give you the actual front-end specs rather than a secondhand guess from me. For a deployment you're actively scoping that's worth a direct conversation.

The 50km number is a drone-to-drone figure with both units elevated, which eliminates ground reflections — if you've got both ends on the ground you're looking at the 5km ground-to-ground spec, so worth confirming which deployment geometry you're actually working with before you finalize anything.

Joel Sanchez•July 14, 2026

Hey John, the 50km figure is typically derived under pretty optimistic assumptions - max TX power (often around +10 to +14 dBm depending on the module variant), a receiver sensitivity somewhere in the -100 to -106 dBm range, and basically line-of-sight with elevated antennas, so real-world link margin in an actual deployment can eat into that fast. Would help to know which exact module you're looking at since the datasheet sensitivity numbers vary a decent bit between them - have you pulled the actual link budget table from the spec sheet yet or are you working off the headline number?

Amber Bowman•July 14, 2026

Joel's right on the sensitivity range - also worth factoring in antenna gain on both ends because that 50km headline usually assumes something like a 3-5 dBi setup on each side, and if you're dropping to a basic whip or PCB trace antenna you can kiss a big chunk of that range goodbye pretty quick. What module variant are you looking at, the link budget math gets a lot more concrete once we have the actual datasheet numbers in front of us.