Range extension of the nrf21540

[Gianlucamilani]

Dear DevZone,

within out project we make use of an esb communication between a nrf52840 DK connected to the PC via USB (a "station"), and a custom PCB with a nrf52840 micro-controller mounted on top.

We would like to extend the radio transmission range through the nrf21540. (In particular, we are loosing some packets sent from the custom nrf52840 board).

From the nrf21540 product brief, the stated range extension is 8x if the chip is mounted on both the transmitter and the receiver.

What if the chip is mounted only on the station side (the receiver, i.e. the dev kit in our case)? Is the range increased in that case and how much?

Thank you very mich in advance,

Best regards,

Gianluca Milani

[SwRa]

Hi,

Really sorry for keeping you waiting. Please expect a delay as we are a bit understaffed since it is the holiday season.

Regards,

Swathy

[SwRa]

Hey,

Sorry for the delayed response. If you place the nrf21540 in the receiver side only and if the receiver only receives the data, i.e, one-way communication, it will only improve the receiver sensitivity by a factor of about -100dB and there will be no significant improvement in the range. But if there is two-way communication, i.e, the receiver end also sends data, then there will also be an improvement in the transmitting power of the receiver which will improve the range.

Kind Regards,

Swathy

[Gianlucamilani]

Thank you very much for your answer, 

so this means that actually the -100dB factor improvement in the receiver side is not really effective, right?

Best regards,

Gianluca 

[SwRa]

Hi,

The receiver sensitivity alone cannot improve the range since it only improves the minimum signal strength that a receiver can detect. The transmitted signal does not reach the receiver without improvement in output power. However, the improvement in the transmission power coupled with the improved sensitivity is what improves the range significantly in the nrf21540 range extender. 

Regards,

Swathy