Definition of ratio detector in English:

ratio detector

noun

Electronics
  • A type of FM demodulator commonly used in FM receivers, with two output voltages such that their sum is constant and their ratio (rather than their difference) is proportional to the ratio of the two applied frequency-dependent voltages.

    The result is that insensitivity to changes in amplitude is not confined to the carrier frequency.

Origin

1940s; earliest use found in RCA Review.