What does the MDS of a receiver represent?

In receiver specifications, MDS stands for Minimum Discernible Signal. It defines the absolute weakest signal that can still be detected by the receiver over its own internal noise. Technically, the MDS is usually measured as the signal level at the antenna input that produces a signal-to-noise ratio of 0 dB. This means the signal power is exactly equal to the receiver's noise floor power, resulting in a 3 dB increase in total audio output compared to the noise alone. The other options are simply fabricated acronyms designed to distract you. MDS has nothing to do with meter displays, modulation distortion, or maximum spectrum limits; it is strictly a measure of receiver sensitivity.