| 摘要 |
Methods and apparatus for implementing image rejection in radio receivers or transmitters includes a Weaver image reject mixer modified so that only one local oscillator is used for the highest mixing frequency, and subsequent lower frequency mixing signals fed to the mixers are derived from digital frequency divider networks which produce both in-phase and quadrature versions of their pre-determined output frequencies. By using frequency dividers to generate these subsequent lower frequency signals, the intermediate frequencies walk; and when these frequency dividers are set to divide by multiples of two, generating quadrature signals becomes straightforward.
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