How to Use Dual Antenna simultaneously in NRF21540

[Irfan Memon]

Hi,

We are Designing the Long range module using nRF54L15 with nRF21540 FEM.

Now want to use Dual Antenna simultaneously. we have  Couple of questions

Please guide us how to use.

Can we send same TX Power with both Antenna?. 

Use one in receive mode and one in Transmit mode.

What are the real application using Dual Antenna/Use of Dual Antenna

Please explain it

Regards,

Irfan

[Kazi Afroza Sultana]

Hello Irfan,

We have option of two antennas on FEM; but it is not possible to use both of these simultaneously. 

[Irfan Memon]

Thanks for the reply

Please let me know that what are the advantages of use the dual antenna or what are application of dual antenna

Regards,

Irfan

[PaKa]

Dual antenna is most commonly used for static applications like home or industrial applcations running non-frequency hopping protocols. Zigbee and OpenThread are the most common examples for us.

The dual antenna support will then make it less likely you end out in a multipath shadow as changing the antenna will pull you out of this. For frequency hopping protocols like Bluetooth this is less of an issue as the changing of frequency also pulls you out of multipath shadows.

[Kazi Afroza Sultana]

Hello Irfan,

The advantage of having dual antenna is to support antenna diversity. You can switch between antennas depending on the communications surrounding. The FEM must provide, at least, the capability to switch between antennas. This allows, for example, a simple binary analog switch to act as a FEM for antenna diversity.

The antenna diversity module allows an 802.15.4 radio device, equipped with two antennas, to select, during transmission or reception, the best antenna for improving the radio communication parameters in complex radio environments.

Switching the antenna might help in minimizing the negative effects that certain phenomena (like multiple reflections on radio path, multipath fading, or antenna cross-polarization) have on the quality of radio communications.

You can read about this here Antenna diversity in details.

Thanks.

BR

Kazi