Patent ID: 7016662

Claim:
A radio frequency (RF) up-convertor with reduced local oscillator leakage, for emulating the modulation of an input signal x(t) with a local oscillator signal having frequency ƒ, said up-convertor comprising: a synthesizer for generating mixing signals φ 1 and φ 2 which vary irregularly over time, where: φ 1 *φ 2 has significant power at the frequency ƒ of said local oscillator signal being emulated; neither φ 1 nor φ 2 has significant power at the frequency ƒ of said local oscillator signal being emulated, and said mixing signals φ 1 and φ 2 are designed to emulate said local oscillator signal having frequency ƒ in a time domain analysis; a first mixer coupled to said synthesizer for mixing said input signal x(t) with said mixing signal φ 1 to generate an output signal x(t) φ 1 ; and a second mixer coupled to said synthesizer and to the output of said first mixer for mixing said signal x(t) φ 1 with said mixing signal φ 2 to generate an output signal x(t) φ 1 φ 2 , said output signal x(t) φ 1 φ 2 emulating the modulation of said input signal x(t) with said local oscillator signal having frequency f.