Patent ID: 8456251

Claim:
An oscillator for generating an adjustable-frequency signal, said oscillator comprising: a principal looped system comprising: a principal phase shift device including an input and an output and comprising at least one principal phase shift stage for shifting the phase of a principal signal by an adjustable phase shift value, each principal phase shift stage defining a level of phase shift, said principal signal being a cosine or a sine, a principal resonator including a principal resonator input and a principal resonator output, the principal resonator input being connected to the output of said principal phase shift device and the principal resonator output being connected to an input of said principal phase shift device; a secondary looped system comprising: a secondary phase shift device including an input and an output and comprising a plurality of secondary phase shift stages, connected in series, and a secondary resonator including a secondary resonator input and a secondary resonator output, the secondary resonator input being connected to the output of said secondary phase shift device and the secondary resonator output being connected to the input of said secondary phase shift device and to the input of said principal phase shift device, and the output of the principal resonator being connected to the input of said secondary phase shift device, said oscillator comprising at least one means for adjusting the phase shift produced by each of said principal and secondary phase shift stages by multiplication of two signals in quadrature by two control signals and by summing; wherein for each principal or secondary phase shift stage of one of said principal or secondary looped systems: one of said signals in quadrature is the principal signal, and the other of said signals in quadrature is the secondary signal.