nRF52840 external antenna

RE: nRF52840 external antenna

Martin Sivertsen — Fri, 19 Nov 2021 15:37:01 GMT

Hi,

Trying to connect the RF signal on the nRF52840 dongle to a different board or antenna sounds like a real challenge, and I have a hard time believing you can accomplish it without significant loss to the signal.

Also, if soldering the dongle down on another board, make sure that the part on the dongle with the antenna hangs outside of the board below it, because it is designed to not have any metal under it.

Regarding nRF52840 being on backorder, we also have nRF52833 and nRF52820 which have the same radio as the nRF52840 , but a reduced feature set, you can see if you can fins any of those two if they fit your project.

Best regards,

Martin S.

RE: nRF52840 external antenna

Joel V — Thu, 18 Nov 2021 14:19:40 GMT

[quote userid="13081" url="~/f/nordic-q-a/81448/nrf52840-external-antenna/338596#338596"]There are also other good range extenders out there, but the bottom line is that you'll have to design a custom board with an nRF52840 and range extender, you can't connect a range extender or different antenna to the nRF52840 dongle as it is. [/quote]

I am doing a custom board. The problem is that the nRF52840s are backorder right now at our distributor and so I am trying to make our custom board by soldering the dongle on it. That way, the signal became very poor (probably due to the custom board causing interference on the signal). That's why I wanted to add an extender to the dongle. That'S also why I wanted to bypass the antenna of the dongle with another set of antenna that would be already tuned. I will try something with the nRF21540.

RE: nRF52840 external antenna

Martin Sivertsen — Thu, 11 Nov 2021 13:59:36 GMT

Hello Joël,

[quote user=""]I was wondering if you could give me the Pi-network for an antenna of this size (105 mm) with frequency of about 2.4 GHz - 2.5 GHz so I could try to have more range that would help me very much.[/quote]

The values of the components in a PI- shaped tuning network need to be determined by doing measurements on the finished board itself, as the size and shape of the ground plane, vicinity to other components or materials can affect the antenna performance.

As I said in my last post: You won't get a lot more range with a different antenna (especially if the original antenna is tuned correctly).

[quote user=""] Further more I was wondering if you had some gerber file of PA and LNA for such antenna to add it to my board with the nRF52840.[/quote]

We have the nRF21540 range extender, but the design is quite new so we don't have any PCB layout publicly available just yet.
There are also other good range extenders out there, but the bottom line is that you'll have to design a custom board with an nRF52840 and range extender, you can't connect a range extender or different antenna to the nRF52840 dongle as it is.

Best regards,

Martin S.