Page "Sensitivity (electronics)" Paragraph 17

Because receive sensitivity indicates how faint an input signal can be to be successfully received by the receiver, the lower power level, the better.

Lower power for a given S / N ratio means better sensitivity since the receiver's contribution is smaller.

When the power is expressed in dBm the larger the absolute value of the negative number, the better the receive sensitivity.

For example, a receiver sensitivity of-98 dBm is better than a receive sensitivity of-95 dBm by 3 dB, or a factor of two.

In other words, at a specified data rate, a receiver with a-98 dBm sensitivity can hear signals that are half the power of those heard by a receiver with a-95 dBm receiver sensitivity.