Frequency mixer

In electronics, a mixer, or frequency mixer, is an electrical circuit that creates new frequencies from two signals applied to it. In its most common application, two signals are applied to a mixer, and it produces new signals at the sum and difference of the original frequencies. Other frequency components may also be produced in a practical frequency mixer.

This article is about non-linear mixing operating in the frequency domain. For other types of mixers, see electronic mixer.

Mixers are widely used to shift signals from one frequency range to another, a process known as heterodyning, for convenience in transmission or further signal processing. For example, a key component of a superheterodyne receiver is a mixer used to move received signals to a common intermediate frequency. Frequency mixers are also used to modulate a carrier signal in radio transmitters.

An unbalanced mixer, in addition to producing a product signal, allows both input signals to pass through and appear as components in the output.

A single balanced mixer is arranged with one of its inputs applied to a balanced () circuit so that either the local oscillator (LO) or signal input (RF) is suppressed at the output, but not both.

differential

A double balanced mixer has both its inputs applied to differential circuits, so that neither of the input signals and only the product signal appears at the output. Double balanced mixers are more complex and require higher drive levels than unbalanced and single balanced designs.

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Frequency multiplier

Subharmonic mixer

Product detector

Pentagrid converter

Beam deflection tube

Ring modulation

Gilbert cell

Optical heterodyne detection

Intermodulation

Third-order intercept point

Rusty bolt effect

RF mixers & mixing tutorial

This article incorporates public domain material from Federal Standard 1037C. General Services Administration. Archived from the original on 2022-01-22.