A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency. Edwin Howard Armstrong developed the concept, though Lucien Lévy, Walter Schottky, Henry Round, and John Renshaw Carson worked along the same lines. Superheterodyne receiver systems are still a modern feature, and can be used for other modes than AM.
According to Nahin, "Any receiver that shifts the antenna signal frequencies to new locations in the spectrum is a heterodyne receiver." The prefix super is reserved for those receivers that include a tunable antenna filter for image rejection, and intermediate frequency amplification that suppresses adjacent channels. "This sort of receiver circuitry results in an easy-to-use radio that has reliably consistent tuning with a clearly audible audio output. It is the gold standard of modern AM broadcast radio."