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MultiNav Pro+ BLE - does output power scale down automatically at close range?

John JacksonJune 23, 2026
Been running the MultiNav Pro+ BLE module in a project where I have nodes at varying distances - some are like 10 meters apart, others are closer to the upper end of the range spec. Works great honestly, no complaints there. But I got curious about power consumption and started wondering if the module does any kind of adaptive TX power, like automatically backs off the output when the RSSI indicates the remote node is close by. Or is it just running at max power all the time regardless of link quality?
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Replies

AdamJune 23, 2026
@John Jackson good question — honestly this is one of those things that trips up a lot of people coming from standard BLE modules where adaptive TX power (APC) is sometimes baked into the stack.
 
The MultiNav Pro+ is built around the STM32WB07 and the external PA stage is what gets you that extended range. The short answer is that out of the box it's not automatically scaling TX power based on RSSI — it's running at the configured output level consistently, which is what guarantees you hit the range spec reliably at the far end. The tradeoff is that yeah, your 10-meter nodes are getting way more power than they need.
 
That said, you can absolutely implement this yourself in firmware. The STM32WB07 BLE stack exposes RSSI per connection, so the pattern would be to read RSSI periodically, define threshold bands, and call the TX power adjustment API accordingly — it's not a huge lift if you want to prototype it. If you're on the AI Firmware Builder in the Club, that's actually a solid use case to throw at it and see what it generates as a starting point.
 
Worth flagging to Moamen too if this is something you'd want as a toggle in a future firmware release — the use case makes sense for mesh deployments where you've got mixed-distance nodes and want to stretch battery life on the close-range pairs.
Michael MartinJune 23, 2026
The MultiNav Pro+ BLE doesn't do adaptive TX power out of the box - it holds whatever power level you configure at init and just stays there. You'd have to implement your own control loop using the RSSI readings to dial it back via the TX power register when you know nodes are close, which is pretty doable but definitely manual. Worth it for battery-sensitive nodes honestly.
Thomas MooreJune 23, 2026
Yeah Michael's right, no automatic backoff - I went through the same thing on a mesh project and ended up writing a pretty simple loop that checks RSSI every few seconds and steps the TX power down in 4dBm increments when the link is solid. Took maybe an afternoon to get it stable and the battery life difference on the closer nodes was noticeable. If you want I can dig up that code and drop it here.
Barbara AndersonJune 23, 2026
Thomas if you can share that code that'd be super helpful - would love to see how you're handling the stepping logic especially around the thresholds, because getting those wrong is where I always end up with a flickery link that can't make up its mind.
David TaylorJune 23, 2026
Thomas yes please drop that code, been curious how you're handling hysteresis on the thresholds - that's exactly where I'd expect it to get wobbly if you're just doing a straight RSSI comparison with no dead band around the step points.
Sarah MillerJune 23, 2026
Thomas please do drop that code - the hysteresis thing David mentioned is real, I burned way too long on a similar loop before I added a dead band and suddenly everything stopped hunting. Curious whether you're tracking a rolling average of the RSSI samples or just going off the raw reading before you make a step decision.

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