Systems, methods, and devices are described for generating multi-tone waveforms. A count signal having a count value is generated. A plurality of step values and a plurality of phase values are received. For each increment of the count value, an index value corresponding to each step value of the plurality of step values is calculated based on the step value, the count value, and a respective phase value of the plurality of phase values. A tone point value corresponding to each calculated index value is determined to generate a plurality of tone point values for each increment of the count value. The determined tone point values are summed to generate a corresponding waveform point for each increment of the count value. A waveform is generated as a sequence of generated waveform points.

A method and apparatus for generating an RF signal uses digital signal components to generate a synthesized RF signal having a plurality of frequency components. An analog filter is used to filter the synthesized RF signal. The analog filter is a tunable, active feedback circuit having one or more variable resonators and a variable gain block connected in a signal loop that is defined by a passband. The analog filter is tuned such that the passband of the analog filter overlaps one or more desired frequency components of the plurality of frequency components of the synthesized RF signal, and such that the passband has a relative bandwidth of about 1% or less.

A direct digital synthesizer (DDS) circuit. The circuit includes a first input to receive a first fixed frequency clock signal having a first frequency, a second input to receive a second fixed frequency clock signal having a second frequency lower than the first frequency, and an output to provide an output frequency that is based at least in part on a frequency control word (FCW). The DDS circuit may include a frequency correction circuit having a first input to receive the first clock signal, a second input to receive the second clock signal, and a third input to receive the FCW, and an output to provide a frequency error of the first clock signal, the frequency error determined using the second clock signal and FCW. Alternatively, or in addition to, the DDS circuit may include an all-digital phase lock loop to correct for frequency wander of the first clock signal.

An RF signal is tuned by: producing a first signal at a first frequency using a digital sequence generator; filtering the first signal using a frequency-tunable tracking filter that is tuned to the first frequency, the tracking filter comprising one or more variable resonators; tuning the tracking filter from the first frequency to a second frequency over a transition period; and tuning the first signal to the second frequency by causing the digital sequence generator to transition between two or more states during the transition period. The two or more states are selected such that, immediately after the transition period, the analog signal substantially matches a desired steady state at the second frequency.

Systems and methods related to charge locking circuits and a control system for qubits are provided. A system for controlling qubit gates includes a first packaged device comprising a quantum device including a plurality of qubit gates, where the quantum device is configured to operate at a cryogenic temperature. The system further includes a second packaged device comprising a control circuit configured to operate at the cryogenic temperature, where the first packaged device is coupled to the second packaged device, and where the control circuit comprises a plurality of charge locking circuits, where each of the plurality of charge locking circuits is coupled to at least one qubit gate of the plurality of qubit gates via an interconnect such that each of the plurality of charge locking circuits is configured to provide a voltage signal to at least one qubit gate.

The disclosed embodiments relate to a system that compactly stores time-series sensor signals. During operation, the system receives original time-series signals comprising sequences of observations obtained from sensors in a monitored system. Next, the system formulizes the original time-series sensor signals to produce a set of equations, which can be used to generate synthetic time-series signals having the same correlation structure and the same stochastic properties as the original time-series signals. Finally, the system stores the formulized time-series sensor signals in place of the original time-series sensor signals.

An analog-to-digital conversion method, an analog-to-digital converter and an image sensor, are provided. The analog-to-digital conversion method includes a first conversion period and a second conversion period; in the first conversion period and the second conversion period, a first counter and the second counter have different effective clock edges and work in a time-sharing way using the first count clock signal and the second count clock signal respectively; in the second conversion period, count directions of the first counter and the second counter are reversed, and the count results in the first conversion period are used as an initial value of the second conversion period; and the conversion result is output based on the first count result and the second count result.

Systems and methods related to charge locking circuits and a control system for qubits are provided. A system for controlling qubit gates includes a first packaged device comprising a quantum device including a plurality of qubit gates, where the quantum device is configured to operate at a cryogenic temperature. The system further includes a second packaged device comprising a control circuit configured to operate at the cryogenic temperature, where the first packaged device is coupled to the second packaged device, and where the control circuit comprises a plurality of charge locking circuits, where each of the plurality of charge locking circuits is coupled to at least one qubit gate of the plurality of qubit gates via an interconnect such that each of the plurality of charge locking circuits is configured to provide a voltage signal to at least one qubit gate.

A signal control system for quantum computing includes a signal source, a waveform calibration circuit, a qubit control line, and a qubit module. The signal source is configured to generate an original control signal. The waveform calibration circuit includes at least one IIR digital filter. The IIR digital filter is configured to perform waveform calibration on the original control signal to obtain a calibrated control signal. The qubit control line is configured to guide the calibrated control signal to the qubit module. The qubit module is configured to generate a qubit. The calibrated control signal acts on the qubit after passing through the qubit control line, so as to control the qubit.

High frequency arbitrary waveforms have applications in radar, communications, medical imaging, therapy, electronic warfare, and charged particle acceleration and control. State of the art arbitrary waveform generators are limited in the frequency they can operate by the speed of the Digital to Analog converters that directly create their arbitrary waveforms. The architecture of the Harmonic Arbitrary Waveform Generator allows the phase and amplitude of the high frequency content of waveforms to be controlled without taxing the Digital to Analog converters that control them. The Harmonic Arbitrary Waveform Generator converts a high frequency input, into a precision, adjustable, high frequency arbitrary waveform.