Direct-conversion receiver

A direct-conversion receiver (DCR), also known as a homodyne, synchrodyne, zero intermediate frequency receiver (zero-IF receiver), is a radio receiver design that demodulates the incoming radio signal using synchronous detection driven by a local oscillator whose frequency is identical to, or very close to the carrier frequency of the intended signal. This contrasts with the standard superheterodyne receiver, which uses an initial conversion to an intermediate frequency (IF).

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