nRF52840 Dongle antenna characteristics

[NewtoM]

Hello,

we are currently trying to create sensor networks with the nRF52840 Dongle. Our first RSSI measurements in the field show that the orientation (rotation) of the dongle can account for differences in the RSSI values of about 10-15%. We would like to know the theoretical best orientation of the antenna for our installations. Is there any public documentation on the antenna characteristics of the Dongle?

Thanks in advance,
Tamas

[Marjeris Romero]

Hi Tamas,

No, we haven't characterize the nRF52840 dongle antenna. The radiation pattern of the antenna will change with where and how the dongle is plugged in, so it's difficult to say something about the radiation pattern in general.

Best Regards,

Marjeris

[NewtoM]

Hi Marjeris,

that's a pity. We wanted to know the radiation pattern exactly to optimize where and how the dongle gets plugged in.

Tamas

[Marjeris Romero]

Hi Tamas,

Yes, unfortunately this kind of measurements you will need to do yourself, since the radiation pattern will completely depend in the enviroment you are working with. So there will be a bit of trial and error when placing the sensors in a sensor network.

Best Regards,

Marjeris

[NewtoM]

Ok, thank you Marjeris.

Just for the case someone looks for the same information, we have found that in free field (and without any obstacles near the Dongle) there exists a "best direction", which I have drawn onto the schematics from Nordic.

Furthermore, I've found the following topic-related sites/documents useful:

http://www.gsm-modem.de/M2M/m2m-faq/embedded-antenna-bluetooth-gps-gnss/

http://www.antennamagus.com/newsletter-2016-1.php

http://www.cypress.com/file/136236/download

http://www.ti.com/lit/an/swra351a/swra351a.pdf

Tamas