Patent ID: 6959178
Filing Date: 2005-10-25
Classification: H03D,H04B

Abstract:
1. An upconverter with image rejection capabilities, comprising: a. a mixer circuit having inputs for receiving a signal to be upconverted and an oscillator signal to be mixed with the signal to be upconverted, the mixer generates a mixer output signal at a desired sideband frequency and an image signal at an image frequency; and b. a mixer tuned load circuit coupled to the mixer circuit that resonates and passes signals in a desired passband corresponding to the mixer output signal at the desired sideband frequency, and attenuates signals in an attenuation band that includes the image signal at the undesired image frequency; c. a pre-amplifier coupled to the output of the mixer circuit to increase the power of the mixer output signal, wherein the pre-amplifier outputs a pre-amplified signal; and d. a pre-amplifier tuned load circuit coupled to the output of the pre-amplifier to resonate and pass signals in the desired passband and, which attenuates signals in the attenuation band.