Patent ID: 7194044
Filing Date: 2007-03-20
Classification: H03D,H04B

Abstract:
1. Down conversion circuitry for use in a radio transceiver for down converting a received RF information signal to a base band information signal in two stages wherein a first said stage converts said RF information signal to an IF information signal and a second said stage converts said IF information signal to said base band information signal, said down conversion circuitry comprising: a mixer component configured for down converting said RF information signal to said IF information signal using an RF oscillator signal; an image rejection mixer component configured for down converting said IF information signal to said base band signal using an IF oscillator signal and achieving image signal rejection of said IF information signal; and, a frequency synthesizer configured for generating one or more of said RF or IF oscillator signals, or combinations thereof, wherein said IF oscillator signal is an integer (N) sub-harmonic of said RF oscillator signal and a frequency value of said IF oscillator signal is pre-selected to be within an operating frequency band of said image rejection mixer component.