A BT4.1 & BT4.2 module maker based on Nordic nRF51 & nRF52 solution
(nRF51822 & nRF51422 & nRF52832 & nRF51802)
What is dBM?
From Spec sheet, we can find the output power always stated as dBM.
Transmitting power (+4dBM~-20dBM) / Receiving Sensitivity (-96dBM)
dBm is the unit for radiowave, it is a way to express the comparison between the reference signal value
The reference value is 0dBM at 1mW, the unit represented as shown below
1/10000 times = -40 dBm
1/1000 times = -30 dBm
1/100 times = -20 dBm
1/10 times = -10 dBm
1mW = 0 dbm ← Reference Signal Value
10 times = 10 dBm
100 times = 20 dBm
1000 times = 30 dBm