Design Consideration for Customized nRF9160 PCB with External GPS & LTE Antenna

[anthony_ng@1503]

Dear Nordic Team,

I am asking about the HW integration consideration for the external antennas. Our team is designing a prototype PCB with nRF9160. We plan to use it with U.FL connectors and external antennas for GPS and LTE.

As I record from this thread, the SWF connector on nRF91-DK and thingy91 is designed for testing purposes, not for connecting external antennas. I am confused about the design guidelines for external antennas.

Should I follow the design guidelines and treat the external antennas like the chip antenna on DK to add the matching network and LNA accordingly?

Many thanks,
Anthony

[Michal]

Hello Anthony,

As I record from this thread, the SWF connector on nRF91-DK and thingy91 is designed for testing purposes, not for connecting external antennas. I am confused about the design guidelines for external antennas.

Yes, the SWF connector on our DK is for RF measurement purposes.

Should I follow the design guidelines and treat the external antennas like the chip antenna on DK to add the matching network and LNA accordingly?

the nRF9160 is matched to 50 ohm, so should be the U.FL connectors. For the GPS LNA you may need to add an impedance-matching network, yes. It could be also included in the external antenna module as well, so you will have to investigate that and possibly follow the chosen antenna's design guidelines.

I would recommend looking at the nRF9160 DK hardware files that can be found in the "download" section as well.

Best regards,

Michal