The present disclosure provides a method for analyzing a signal, the method comprising receiving an incoming square-wave-like signal that comprises a predetermined frequency and a variable duty cycle, continuously forming the first derivative of the incoming square-wave-like signal, and determining at least one of the frequency, and the duty cycle of the received signal based on the first derivative. Further, the present disclosure provides a measurement application device.

Circuitry and method of operating a circuit for monitoring a clock signal having phase-to-phase variation is disclosed. The method comprises adding a fixed number of bits to a pulse count of a reference phase instance for a high or low phase to yield a modified added pulse count when detecting a clock slow abnormality, subtracting the fixed number of bits from the pulse count of the reference phase instance to yield a modified subtracted pulse count when detecting a clock fast abnormality, comparing the modified added pulse count to a pulse count for an immediately subsequent phase instance of the high or low phase count of the clock signal when detecting the clock slow abnormality, and comparing the modified subtracted pulse count to the pulse count for the immediately subsequent phase instance of the high phase or low phase count of the clock signal when detecting the clock fast abnormality.

Techniques are provided for non-linear filtering of a signal for improved pulse detection and pulse width discrimination. A system implementing the techniques according to an embodiment includes a first linear filter configured to filter an in-phase component of a received signal to a downsample bandwidth and a second linear filter configured to filter a quadrature phase component of the received signal to the downsample bandwidth. The system also includes a magnitude calculation circuit coupled to outputs of the first linear filter and the second linear filter and configured to generate a magnitude signal based on the filtered in-phase component and the filtered quadrature phase component of the received signal. The system further includes a median filter processor coupled to an output of the magnitude calculation circuit and configured to apply a median filter to the magnitude signal to generate a filtered signal having reduced noise while maintaining sharp edge transitions.

Techniques are provided for non-linear filtering of a signal for improved pulse detection and pulse width discrimination. A system implementing the techniques according to an embodiment includes a first linear filter configured to filter an in-phase component of a received signal to a downsample bandwidth and a second linear filter configured to filter a quadrature phase component of the received signal to the downsample bandwidth. The system also includes a magnitude calculation circuit coupled to outputs of the first linear filter and the second linear filter and configured to generate a magnitude signal based on the filtered in-phase component and the filtered quadrature phase component of the received signal. The system further includes a median filter processor coupled to an output of the magnitude calculation circuit and configured to apply a median filter to the magnitude signal to generate a filtered signal having reduced noise while maintaining sharp edge transitions.

A high-frequency QRS waveform curve analysis method comprises: acquiring a high-frequency QRS waveform curve; selecting the high-frequency QRS waveform curve in a preset time period as a reference waveform curve; selecting a point with the minimum root-mean-square voltage on the reference waveform curve as a first reference point; selecting a second reference point meeting a first selection condition and a third reference point meeting a second selection condition, wherein the time of the first reference point is later than that of the second reference point and earlier than the third reference point; based on the first reference point and the second reference point, determining an amplitude falling relative value; based on the first reference point and the third reference point, determining an amplitude rising relative value. If the amplitude falling rising relative values meet a preset condition, determining reference information according to the high-frequency QRS waveform curve.

One embodiment is a method of deconvolving overlapping first and second pulses in a photon-counting CT scanning system, the method comprising detecting a first pulse event having a first detected level; detecting a second pulse event having a second detected level; determining an amount of time that elapses between the detected first pulse event and the detected second pulse event; and reconstructing the first pulse and the second pulse using the first and second detected levels, the duration of time between the first and second pulse events, and a known pulse shape.

Secure circuitry of an integrated circuit detects a duration of a clock cycle of a crystal oscillator external to the integrated circuit, using a digital ring oscillator internal to the integrated circuit and having a higher frequency than the crystal oscillator. The secure circuitry calculates a variation in the duration of the clock cycle. In response to the duration being greater than a maximum duration limit, the duration being less than a minimum duration limit, and/or the variation being greater than a maximum variation limit, the secure circuitry performs an action.