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maniacbug / RF24

Arduino driver for nRF24L01
http://maniacbug.github.com/RF24
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How to get signal strength? #14

Open kermitas opened 11 years ago

kermitas commented 11 years ago

Hello,

thank you ManiacBug for RF24 and RF24Network!

I have a question. Is there a way to check signal strength between trasmitter and receiver??

Thanks, Arthur.

[PS Chapter 6.4 of nRf24L01+ documentation (http://www.nordicsemi.com/kor/content/download/2726/34069/file/nRF24L01P_Product_Specification_1_0.pdf) describes something like RPD (Received Power Detector measurements).]

etemu commented 11 years ago

You may read out the register 09 manually about 170µs after you switch over to receive mode. I would sample over a period and calculate an average. Please keep in mind that it is only a rough estimation and depends on external factors like the ambient temperature.

The status of RPD is correct when RX mode is enabled and after a wait time of Tstby2a +Tdelay_AGC= 130us + 40us. The RX gain varies over temperature which means that the RPD threshold also varies over temperature. The RPD threshold value is reduced by - 5dB at T = -40°C and increased by + 5dB at 85°C.