The 5G Moto Mod on a Moto Z3.

  • Motorola’s 5G Moto Mod has a feature to limit millimeter wave radiation exposure.
  • An FCC filing shows that the add-on has several sensors to detect fingers around the module.
  • Antennas close to those fingers will shut down in order to reduce exposure.


The 5G Moto Mod will allow the Moto Z3 to become one of the first commercially 5G-enabled smartphones in the world. We’re inching ever closer to a release, and an FCC filing for the add-on has revealed it has a way to limit radiation exposure from millimeter waves.

Motorola’s filing, spotted by The Verge, mentions that the 5G Moto Mod has capacitive and proximity sensors to detect your fingers. These sensors aren’t for Edge Sense functionality, however, as it shuts off any antenna close to your fingers.

“The control mechanism is a simple one in which, if proximity detectors indicate the potential presence of the user within a roughly conical region in front of the module where power density may approach the MPE [maximum permissable exposure – ed] limit, that module is disabled from use by the modem. This terminates and prevents transmission from the module in question until the condition is cleared,” reads an excerpt of the filing.

Any reason for the feature?

In any event, the outlet notes that millimeter wave radiation is non-ionizing, and is also encountered at airport security scanners. But it’s still interesting to see Motorola take this approach in order to reduce exposure — even if the module is only approaching (and not exceeding) FCC limits.

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The feature seems to imply that radiation is a concern of some kind in the transition to 5G, even if it’s still within the allowed limits. Or it could simply be a case of Motorola being excessively cautious. We’ve contacted the manufacturer for comment regarding the functionality, and will update the story if/when they respond.

Motorola’s filing also notes that the 5G Moto Mod is compatible with the Moto Z3 Pro. Unless this is an error, it means that we should expect a souped-up Moto Z3. The device packed 2017’s Snapdragon 835 chipset and a ho-hum 3,000mAh battery, so a Moto Z3 Pro would presumably offer a more powerful chipset and bigger battery. It’s unclear when this model will launch, but a release alongside the 5G Moto Mod seems like a sensible decision.

NEXT: Here’s our first look at LG V50 — 5G, triple cameras, and a 4,000mAh battery