Editing Product detector (section)

{{short description|Type of demodulator}}
{{Unreferenced|date=December 2009}}

A '''product detector''' is a type of [[demodulator]] used for [[amplitude modulation|AM]] and [[Single-sideband modulation|SSB]] signals.  Rather than converting the envelope of the signal into the decoded waveform like an [[envelope detector]], the product detector takes the product of the modulated signal and a [[local oscillator]], hence the name. A product detector is a [[frequency mixer]].

Product detectors can be designed to accept either [[Intermediate frequency|IF]] or [[Radio frequency|RF]] frequency inputs.  A product detector which accepts an IF signal would be used as a demodulator block in a [[superheterodyne receiver]], and a detector designed for RF can be combined with an RF amplifier and a low-pass filter into a [[Direct conversion receiver|direct-conversion receiver]].