improve BLE sensitivity

[Carey]

i use a 52832 module scan BLE advertisement signal, and found it can recived lowest DB value is -92db.  but i use my Phone to scan same advertisement signal, it can recived lowest DB value is -103db.   It means my phone can reviced more far signal than 52832 module.  So my question is how to improve this, i want my 52832 module can recived more weak signal. 

[Carey]

i use nRF5 SDK v12.3.0     ble_central\ble_app_uart_c    to scan BLE advertisement and see the db value in the p_adv_report->rssi.

and see db value in the phone use nrf connect .

[Sigurd]

The RSSI is typically not very accurate when you come near the sensitivity limit, in the PS we list ±2 accuracy within the RSSI range -90 to -20 dBm. I would assume phones also have a similar behavior. If you want any valid sensitivity measurement you need dedicated tester, like a R&S CMW500 or Anritsu MT8852B. See this (Chapter 6)and this whitepaper.