FCC and minimum distance requirements for NRF9160 LTE antenna (end-devices etc)

[CRD]

We have pre-production product (based similar to the NRF9160dk setup with a NRF9160 (LTE-M, GPS) and a bridged NRF52840 (BLE). We are working through certifications for CSA, CE, FCC etc...

One big sticking point is this line in the FCC certification for the NRF9160:
"The antenna of this transmitter must provide a separation distance of at least 20 cm from all persons. Installers and end-users must be provided with antenna installation instructions and transmitter operating conditions and instructions for satisfying RF exposure compliance."

While our product is normally not near any humans while operating, there is essentially no reasonable way to ensure a human could never come within 20cm of the antenna if they wished to. We cannot put a 20cm radius protective dome around the antenna.

We were recommended to check out "end-device" modules but all of the devices we have seen so far re-use the Nordic FCC ID and maintain the same 20cm stipulation. We have considered SAR testing but this seems like an extensive testing and may require assistance/participation from Nordic Semi to actually complete it.

I'm not understanding what the end-devices actually solve towards certifications since we would still need to do unintentional radiation FCC testing once we attach it to our boards or make any modifications to our underlying boards.

We only transmit every few minutes and can provide instructions and warnings to not use the device while the antenna is activated but otherwise I do not see how we can reasonable resolve this.

We are really stuck on this and trying to understand what options we have.

Best regards

[mathiaso]

Hi again, Colin.

One big sticking point is this line in the FCC certification for the NRF9160:
"The antenna of this transmitter must provide a separation distance of at least 20 cm from all persons. Installers and end-users must be provided with antenna installation instructions and transmitter operating conditions and instructions for satisfying RF exposure compliance."

This means that the device in most cases will be 20 cm or more away from people. In other words, is not a body-worn device (or carried in a pocket, etc.). And that if it is a body-worn device there is additional certification needed.

Best regards,
Mathias

[CRD]

Hi Mathias,

Thank you for this clarification. I will take this to our testing partner as our device is not a body-worn device (nor carried in a pocket).

As for the modules. Do you have any clarification on the end-devices vs using the NRF9160 and the NRF52840 chips.

The NRF9160 has an FCC ID and we are using it within the manufacturer parameters, so we would need unintentional radiation testing then we can re-use the FCC ID.

The NRF52840 doesn't seem to have an FCC ID? (at least that I can find) So in this case I assume we should use a module that is FCC certified instead of the chip?

[mathiaso]

Hi, Colin.

CRD said:

As for the modules. Do you have any clarification on the end-devices vs using the NRF9160 and the NRF52840 chips.

Do you mean what will be the difference between using the SiP and SoC vs using pre-certified modules?

CRD said:

The NRF52840 doesn't seem to have an FCC ID? (at least that I can find) So in this case I assume we should use a module that is FCC certified instead of the chip?

The device itself can't have an FCC ID. If that's what you want you'll need a pre-certified module, as you say.

We're entering the Easter holidays now, so I won't be able to answer any further questions until next week.

Best regards,
Mathias