What is 12dB SINAD?
SINAD is a measurement of signal, noise and distortion. It is defined as:
SINAD value = Signal + Noise + Distortion / Noise + Distortion
12dB SINAD means a SINAD value where the ratio of [SIGNAL + NOISE + DISTORTION] to the [NOISE + DISTORTION] level is +12dB. In dBs, this would be the arithmetic difference between the 2 parts.
A figure of 12dB is taken as the industry standard to measure RX sensitivity and you would normally see eg. 0.25uV at 12dB SINAD, meaning that a signal input level at the antenna would need to be 0.25uV to produce a SINAD of 12dB.