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

[flau]

Hi Everyone,

We run into a similar situation.  We designed a handheld product with the nRF9160.  The product will normally transmit a small amount of data once every 20 minutes.  But upon user request, it can transmit once every 5 minutes for 3 cycles.  After that it will go back to a 20 minutes duty cycle.  DEKRA has completed RF exposure tests on the product.  Final test reports are available.  Test results show that the product is below the maximum permitted power at these duty cycles at less than 20cm.  We are exempted from doing a SAR test on the product.  However, DEKRA has to submit a C2PC to FCC in order to include the product duty cycle into account for RF exposure conditions so that our product comply with the SAR exemption requirements.  

We need permission from Nordic in order to proceed with the C2PC.  This is where we stuck right now.  Will Nordic allow us to do a C2PC on the FCC ID?  We are not in a position to re-certify the nRF9160 with our own FCC ID so that we can do a C2PC.  That defeats the whole idea of using a certified module.  What can we do now?

Regards,

Floyd

[mathiaso]

Hi, Floyd.

Could you please create a new separate ticket for your specific case? If it contains confidential information about your project, please make it a private one.

You can link to this ticket in the new one you create.

Best regards,
Mathias

[flau]

Private ticket created.

[mathiaso]

Thank you, Floyd.