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.