Can a Peripheral device know the RSSI for a connected Central

Question

Hello fellow Nordic community,

Assume that a given Peripheral (P) is advertising a BLE GAP signal which allows for multiple connections to be made.

In the vicinity to P we have two central devices (C1, C2) that hear the advertisement signal and connect to P.

(P) - - - - - - < 5 m > - - - - - - (C1)
|
- - - - - - - - - - < 10m > - - - - - - - - - - - - - - - - - - - - - - - - - - - - (C2)

Is it possible to determine on the Peripheral side which connected Central (C1 or C2) that's signal-wise closest to the Peripheral. Hence in the above example determine that C1 is closer than C2?

Thanks for any help!

Cheers,
Kristian

AndreasF · Accepted Answer

Hi. 
 You can use the two functions sd_ble_gap_rssi_get() and sd_ble_gap_rssi_start() to get the RSSI value between a given peripheral and a central. 
 You can find more information about these functions in the infocenter under: 
 nRF52 Series -> SoftDevices -> Your SoftDevice -> Your SoftDevice API -> Your SoftDevice version API -> API Reference -> Generic Access Profile (GAP) 
 Here is the link to the infocenter. 
 With RSSI you can't really state which device is closest in distance, since RSSI is a measurement of signal strength, and lots of factors play a part in that value. 
 I can give you an example: If there is a wall between P and C1, but P and C2 are in line of sight with no obstacles, you might get a higher RSSI value for C2 then C1 even though C2 is 5 meter further away from P. 
 
 - Andreas

Can a Peripheral device know the RSSI for a connected Central

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