Nrf52840-dongle external antenna

[Joel V]

Hi Dev Zone !

I am actually using nrf52840-dongle for wireless communication with the protocol Enhanced ShockBurst (ESB). I would like to connect an external antenna to increase signal range. I already used the nrf24L01 for this purpose and I would like to have the same signal range as this. Is it possible to do so ? If yes can you tell me what circuit would be appropriate to make this antenna optimal in terms of signal power and range ? 

Thank you very much !

Joel V.

[Joel V]

When I say nrf24L01, i am talking of the nrf24L01+PA+LNA

[Joel V]

Update: I tried solder an antenna before the R1 on the mounted board of the nrf52840-dongle and the signal is still unstable and the range does not or almost not increase. Any suggestions ?

[Martin Sivertsen]

Hello Joël,

Have you added a PA and an LNA to the nRF24L01 and would like to do the same on the nRF52840?

How did you attach the PA and LNA to the nRF24L01?

What antenna are you using?

How are you attaching it, do you have pictures?

Any antenna needs to be tuned to the board it is connected to either by adjusting the length of the antenna or by using a matching network/circuitry (the three components that R1 are a part of), I recommend taking a glance at this white paper we have on antenna tuning: https://infocenter.nordicsemi.com/pdf/nwp_017.pdf?cp=17_14

You might get some added range if you get the new antenna properly matched, so that as much as possible of the power from the radio is radiated outwards and not reflected back to the radio, but without an added PA and LNA I can't see that range increasing substantially.

Best regards,

Martin S.