Requirements to reuse nrf9160 FCC certification

[nullinnovations]

Hello-

I'm working on our design for the nrf9160 and I've been trying to wrap my head around the FCC certification. I know that the nrf9160 is an FCC certified module and I know that the host device also has to carry an FCC certification and it may be possible to reuse Nordic's and skip the headache of lab testing and cost. What I'm confused about is what exactly do we need to do to reuse the certification.

1. The Hardware Integration Guide 6.4 mentions the Ethertronics P822601 antenna

    * Is it mandatory to use this exact antenna to reuse the FCC certification?
    * If not, what are the specific technical or regulatory requirements for using an alternate antenna (e.g., gain, type, placement, matching)?

2. Beyond following the recommended stackup and schematics, are there physical layout constraints (antenna clearance, shielding, ground plane requirements) that we must adhere to in order to reuse the FCC certification?

    * Are there any mandatory placement/layout rules documented somewhere?

3. Does adding a gnss antenna affect the certification?

4. Is there some sort of formal documentation/checklist or test reports we need to complete to confirm we're compliant?

5. If we have followed all the design requirements, can we use the nrf9160's certification under the existing FCC ID

I'm looking for a design solution that minimizes the regulatory testing we have to do.
Your help is greatly appreciated.

[ketiljo]

* Is it mandatory to use this exact antenna to reuse the FCC certification?
    * If not, what are the specific technical or regulatory requirements for using an alternate antenna (e.g., gain, type, placement, matching)?

From the FCC ID grant notes:

https://apps.fcc.gov/oetcf/tcb/reports/Tcb731GrantForm.cfm?mode=COPY&RequestTimeout=500&tcb_code=&application_id=3jtQl5brYNZFFgLmKuJglA==&fcc_id=2ANPO00NRF9160

The maximum antenna gain including cable loss for compliance with radiated power limits, RF exposure requirements and the categorical exclusion requirements of 2.1091 is 9.0 dBi for LTE FDD 2 frequency band, 6.0 dBi for LTE FDD 4 frequency band, 7.1 dBi for LTE FDD 5 frequency band, 6.6 dBi for LTE FDD 12 frequency band, 6.9 dBi for LTE FDD 13 frequency band, 6.9 dBi for LTE FDD 14 frequency band, 6.6 dBi for LTE FDD 17 frequency band, 9.0 dBi for LTE FDD 25 frequency band, 7.0 dBi for LTE FDD 26 frequency band and 6.0 dBi for LTE FDD 66 frequency band.

    * Are there any mandatory placement/layout rules documented somewhere?

No requirement except the antenna gain

3. Does adding a gnss antenna affect the certification?

No, but you have to make sure you follow the guidelines https://docs.nordicsemi.com/bundle/nwp_033/page/WP/nwp_033/nwp_033_gps.html

"To avoid RF issues, 30 dB isolation at LTE TX frequencies between the nRF91 device ANT pin and the GNSS input pin should be targeted. In other words, the maximum allowed LTE TX power coupling from the ANT pin to the GNSS input pin at a maximum LTE transmit power of 23 dBm should not exceed -7 dBm."

This normally means an active antenna with a pre-filter, passive antenna plus LNA with a pre-filter or a LNA with a external filter after the antenna. 

4. Is there some sort of formal documentation/checklist or test reports we need to complete to confirm we're compliant?

No, but you have to include a reference in your documentation that the product contains another FCC ID. If you have other transmitters in your system, you either have to make sure that they can't transmit simultaneously or re-test for spurious emissions. 

The usual EMC or non-intentional transmitter testing must always be done (FCC part 15B)