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The Supersonic Heterodyne receiver, or Superheterodyne receiver 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. At the cost of an extra frequency converter stage, the superheterodyne receiver provides superior selectivity and sensitivity compared with simpler designs.The Supersonic Heterodyne receiver, or Superheterodyne receiver 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. At the cost of an extra frequency converter stage, the superheterodyne receiver provides superior selectivity and sensitivity compared with simpler designs. Superheterodyne receivers have better performance because the components can be optimized to work a single intermediate frequency, and can take advantage of arithmetic selectivity.