A non-contact self-injection-locked vital sign sensor is disclosed, which includes transmitting antenna, receiving antenna, self-injection-locked integrated circuit and demodulator. The self-injection-locked integrated circuit includes voltage-controlled oscillator, mixer, two amplifiers and harmonic-frequency power combiner. A frequency-multiplied signal is produced by amplifiers and harmonic-frequency power combiner then transmitted to a living body by transmitting antenna. A frequency-divided signal is produced by voltage-controlled oscillator and mixer then transmitted to voltage-controlled oscillator, then a frequency- and amplitude-modulated signal is produced by the voltage-controlled oscillator then transmitted to demodulator to produce a vital sign. So as to detect vital sign with a higher frequency to increase measurement sensitivity by using a low-cost integrated circuit process. A centrifugal compressor includes a volute base block, a volute cover plate, an impeller, a diffuser-adjusting assembly, a radial constraint assembly, an axial constraint assembly and a driving assembly.

A multilayer ceramic radiofrequency mixer can include a first termination, a second termination, a third termination, and a fourth termination. A plurality of interleaved electrodes may include a first set of electrodes connected with the first termination, a second set of electrodes connected with the second termination, a third set of electrodes connected with the third termination, and a fourth set of electrodes connected with the fourth termination. A plurality of dielectric layers may be disposed between respective electrodes of the pluralities of interleaved electrodes. A dielectric constant of the plurality of dielectric layers may vary less than 10% in response to a DC bias voltage applied to the plurality of interleaved electrodes.

A multilayer ceramic radiofrequency mixer can include a first termination, a second termination, a third termination, and a fourth termination. A plurality of interleaved electrodes may include a first set of electrodes connected with the first termination, a second set of electrodes connected with the second termination, a third set of electrodes connected with the third termination, and a fourth set of electrodes connected with the fourth termination. A plurality of dielectric layers may be disposed between respective electrodes of the pluralities of interleaved electrodes. A dielectric constant of the plurality of dielectric layers may vary less than 10% in response to a DC bias voltage applied to the plurality of interleaved electrodes.

A superconducting device that mixes surface acoustic waves and microwave signals and techniques for fabricating the same are provided. A superconducting device can comprise a superconducting surface acoustic wave resonator and a superconducting microwave resonator. The superconducting device can also comprise a Josephson ring modulator coupled to the superconducting surface acoustic wave resonator and the superconducting microwave resonator. The Josephson ring modulator can be a dispersive nonlinear three-wave mixing element.

A signal up-conversion system is described. The system comprises a signal input for receiving an input signal to be up-converted; an oscillator system for generating an up-conversion signal having a selectable frequency; a mixer coupled to the input and to the oscillator, for combining the input signal and the up-conversion signal and to generate an up-converted signal; at least two filters, each of the at least two filters having different filtering characteristics; a signal output; a switch system configured to couple one of the at least two filters into a signal path between the output of the mixer and the signal output; and a controller configured to control a frequency of the up-conversion signal and a filter of the at least two filters coupled into the signal path by the switch system. A method switching between up-conversion frequencies is also described.

High-saturation power Josephson ring modulators and fabrication of the same are provided. A Josephson ring modulator can comprise a plurality of matrix junctions. Matrix junctions of the plurality of matrix junctions can comprise respective superconducting parallel branches that can comprise a plurality of Josephson junctions operatively coupled in a series configuration. A method can comprise forming a first matrix junction comprising arranging a first group of Josephson junctions as first parallel branches. The method can also comprise forming a second matrix junction comprising arranging a second group of Josephson junctions as second parallel branches. Further, the method can comprise forming a third matrix junction comprising arranging a third group of Josephson junctions as third parallel branches. In addition, the method can comprise forming a fourth matrix junction comprising arranging a fourth group of Josephson junctions as fourth parallel branches.

A phase rotator calibration system is provided. The phase rotator calibration system includes a phase rotator portion having input for receiving an input signal and an output for providing an output signal. A calibration portion is coupled to the phase rotator portion. The calibration portion is configured to determine a phase error based on a phase estimation. The phase estimation is generated by way of an arccosine function.

A phase interpolation circuit includes: a first buffer circuit configured to adjust a rise time or a fall time of a first reference clock signal based on a first control signal to generate a first input clock signal; a second buffer circuit configured to adjust a rise time or a fall time of a second reference clock signal based on a second control signal to generate a second input clock signal; a detection circuit configured to detect a rise time or a fall time of the first input clock signal or the second input clock signal and generate the first control signal and the second control signal according to a detection result thereof; and a mixer circuit configured to generate an output clock signal having a phase between a phase of the first input clock signal and a phase of the second input clock signal.

An aspect includes one or more board layers. A first chip cavity is formed within the one or more board layers, wherein a first Josephson amplifier or Josephson mixer is disposed within the first chip cavity. The first Josephson amplifier or Josephson mixer comprises at least one port, each port connected to at least one connector disposed on at least one of the one or more board layers, wherein at least one of the one or more board layers comprises a circuit trace formed on the at least one of the one or more board layers.

A transposed delay line oscillator including a mode selection filter and a transposed delay line is provided. An output of the transposed delay line is coupled to an input of the mode selection filter to establish an oscillator loop. Based on the transposed delay line output, the mode selection filter generates a mode selection signal including an isolated oscillatory mode, in a Radio Frequency (RF) band. The transposed delay line receives the mode selection signal for transposition to an intermediate frequency of an intermediate frequency (IF) delay line. The IF delay line includes a delay filter and a phase noise suppression loop configured to suppress de-correlated transposition phase noise resulting from a delay of the delay filter. Suppression of phase noise in the IF delay line enables cancellation of transposition phase noise when transposing the IF delay line output to the RF band.