An oscillator circuit (10) for generating quadrature-related first and second oscillation signals having equal frequencies comprises a first oscillation circuit (VCO_I) configured to generate the first oscillation signal having a first controllable frequency, a second oscillation circuit (VCO_Q) configured to generate the second oscillation signal having a second controllable frequency; and a controller (100) configured to enable and disable oscillation of the first and second oscillation circuits (VCO_I, VCO_Q) and to control the first and second controllable frequencies, such that when the oscillation is enabled, the first and second controllable frequencies are controlled to be initially unequal and then to become equal.

Embodiments provide a device that includes a first circuit having a first input to receive a first sine wave signal and a second input to receive a second sine wave signal in quadrature with respect to each other and a current mode logic gate having a first input coupled to a first output of the first circuit and a second input coupled to a second output of the first circuit. The first circuit configured to deliver a first square wave signal and a second square wave signal. The current mode logic gate is configured to deliver a third square wave signal at a first level and a fourth square wave signal at a second level when the first and second square wave signals are simultaneously at their first levels and the first square wave signal is ahead of the second square wave signal.

A quadrature oscillator includes a first oscillator that outputs a first differential signal, and a second oscillator that outputs a second differential signal having phases that are different from those of the first differential signal, wherein the first oscillator includes a first LC resonator having an inductor and a capacitor coupled in parallel, a first cross-coupled circuit having a first pair of cross-coupled transistors coupled to the first LC resonator, a first tail current source coupled to the first pair of transistors, first input differential pair transistors to which the second differential signal is to be input, and a first pair of harmonic resonators disposed in input sections of the first input differential pair transistors, the first pair of the harmonic resonators have a resonance frequency of an odd multiple of a resonance frequency of the first oscillator.

An integrated frequency quadruplet consists of a pair of balanced frequency doublers that are driven in phase quadrature using a hybrid coupler. This approach results, effectively, in a unilateral multiplier that presents a match to the input-driving source, irrespective of the impedance of the doubler stages. The present invention applies this architecture to implement an integrated frequency quadruplet with output frequency of 160 GHz using quasi vertical GaAs varactors fabricated on thin silicon support membranes. The quadruplet has a balanced circuit architecture that addresses degradation issues often arising from impedance mis-matches between multiplier stages. A unique quasi-vertical diode process is used to implement the quadruplet, resulting in an integrated drop-in chip module that incorporates 18 varactors, matching networks and beamleads for mounting. The chip is tailored to fit a multiplier waveguide housing resulting in high reproducibility and consistency in manufacture and performance.

A transformer feed-back quadrature voltage controlled oscillator (QVCO) includes a first VCO; a second VCO; and a dynamic phase error correction circuit, having a plurality of coupling capacitors connected between the first and second VCOs, wherein the capacitances of the coupling capacitors are varied according to a digital control signal to correct a phase error of local oscillating (LO) signals of quadrature phases output by the first and second VCOs.

A transformer feed-back quadrature voltage controlled oscillator (QVCO) includes a first VCO; a second VCO; and a dynamic phase error correction circuit, having a plurality of coupling capacitors connected between the first and second VCOs, wherein the capacitances of the coupling capacitors are varied according to a digital control signal to correct a phase error of local oscillating (LO) signals of quadrature phases output by the first and second VCOs.

A system for generating a radio frequency signal phase-locked to a reference signal. Such a system includes a rotary travelling wave oscillator including a conductive ring and a plurality of sustaining amplifying cells electrically connected to the ring; a programmable multiplexer device designed to electrically connect an input port of the system to an amplifying cell that can be selected from the cells of the plurality. The system is designed so that the oscillator generates the locked radio frequency signal when the reference signal is injected at the input port of the system. A phase difference between the radio frequency signal and the reference signal is a function of the amplifying cell to which the input port is electrically connected via the programming of the multiplexer device.

Embodiments provide a device that includes a first circuit having a first input to receive a first sine wave signal and a second input to receive a second sine wave signal in quadrature with respect to each other and a current mode logic gate having a first input coupled to a first output of the first circuit and a second input coupled to a second output of the first circuit. The first circuit configured to deliver a first square wave signal and a second square wave signal. The current mode logic gate is configured to deliver a third square wave signal at a first level and a fourth square wave signal at a second level when the first and second square wave signals are simultaneously at their first levels and the first square wave signal is ahead of the second square wave signal.

A quadrature oscillation circuit includes a plurality of adjacent quadrature oscillators, wherein a first quadrature oscillator includes a first I-phase inductor, a first Q-phase inductor, and a first drive circuit that generates a first I-phase current passing the first I-phase inductor and a first Q-phase current passing the first Q-phase inductor such that phases of a first I-phase differential signal from the first I-phase inductor are different from phases of a first Q-phase differential signal from the first Q-phase inductor, a second quadrature oscillator includes a second I-phase inductor, a second Q-phase inductor, and a second drive circuit that generates a second I-phase current passing the second I-phase inductor and a second Q-phase current passing the second Q-phase inductor such that phases of a second I-phase differential signal from the second I-phase inductor are different from phases of a second Q-phase differential signal from the second Q-phase inductor.

A quadrature oscillation circuit includes a plurality of adjacent quadrature oscillators, wherein a first quadrature oscillator includes a first I-phase inductor, a first Q-phase inductor, and a first drive circuit that generates a first I-phase current passing the first I-phase inductor and a first Q-phase current passing the first Q-phase inductor such that phases of a first I-phase differential signal from the first I-phase inductor are different from phases of a first Q-phase differential signal from the first Q-phase inductor, a second quadrature oscillator includes a second I-phase inductor, a second Q-phase inductor, and a second drive circuit that generates a second I-phase current passing the second I-phase inductor and a second Q-phase current passing the second Q-phase inductor such that phases of a second I-phase differential signal from the second I-phase inductor are different from phases of a second Q-phase differential signal from the second Q-phase inductor.