Patent ID: 6850749

Claim:
A local oscillator for generating signals at an output frequency, the local oscillator comprising: an oscillatory circuit configured to generate a first in-phase signal and a first quadrature signal, each of the first in-phase signal and the first quadrature signal having a first frequency lower than the output frequency, the first quadrature signal having a phase shift relative to the first in-phase signal; a frequency shifter coupled to receive at least one of the first in-phase signal and the first quadrature signal and configured to generate a second in-phase signal and a second quadrature signal, each of the second in-phase signal and the second quadrature signal having a second frequency substantially equal to the difference between the first frequency and the output frequency; and a first single-sideband mixer coupled to receive the first in-phase signal, the first quadrature signal, the second in-phase signal, and the second quadrature signal and configured to generate an output in-phase signal having a frequency substantially equal to the output frequency.