RSSI Measurement Mechanisms

[Thavish]

Hi,

This is a follow-up question on RSSI measurements. I understand that it's generated from an ADC that measures voltage received from the antenna. My questions are...

• Is the following equation from section 6.20.12.4 of the nRF52480's product documentation relevant in any way? If so is VAL_HARDWARE that generated by the ADC?

• How does the Link Quality Indicator (LQI) factor into RSSI measurements? Is it the reason RSSI appears to saturate beyond a certain value (17dBm in my tests)?

• Is there any further documentation on how RSSISAMPLE is generated?

I understand if any of this is proprietary information and can't be discussed; I'm trying to get as much information on RSSI measurements for a university project and any help would be much appreciated. Thanks.

[ketiljo]

Section 6.20.12.4 is for 15.4 (Thread/Zigbee) and is somewhat different from normal RSSI. The bandwidth is differnent so the measurement (VALhardware) will offset.

The RSSI should be pretty well explained here.

The radio front end is designed to withstand max 10 dBm, anything above this will damage the chip.