A method and device for determining the location-dependent pulse responses in signal transmission from a transmitter in a transmission volume to a receiver in a reception volume, wherein either the transmitter or the receiver is a device fixed in a predetermined location and the other is a movable device includes: continuously emitting a band-limited signal by the transmitter; continuously capturing the signal and recording the signal with time indexing by the receiver; moving the movable device during the emission and capturing of the signal along a trajectory within the transmission or reception volume while continuously capturing the location coordinates of the movable device and recording the location coordinates with time indexing; and numerically solving a linear system of equations, the unknowns of which system of equations represent the pulse responses at discrete sampling points in the transmission or reception volume associated with the movable device.

In systems, such as sensor systems, an output signal of the system (e.g. output of the sensor corresponding to a sensed characteristic) can be generated and provided. In response to a detected error, the output signal can be adjusted to generate an error indication signal pulse to indicate that an error has been detected. The output signal can then be adjusted to return to a signal level corresponding to the sensed characteristic. In response to the error being resolved, an error resolution signal pulse can be generated.

A circuit for detecting a knee of waveform is disclosed in the present invention. The circuit detects the knee and a total oscillation time of a voltage waveform as a load switch of load circuit is turned off. In the circuit, a filter filters the voltage waveform to transmit a reference voltage to a first and a second comparator. When the first and the second comparator determine that the voltage waveform achieves a sum of the reference voltage and a set voltage, the first and the second comparator transmit a first and a second signal to a knee detection module. When the knee detection module receives the first signal rather than the second signal in an oscillation time, or receives the second signal rather than the first signal in the oscillation time, the knee detection module records the knee and trigger a time recorder computes the total oscillation time.

Various embodiments relate to classifying comparators based on comparator offsets. A method may include applying, via a strobe, a first voltage to each of a first input and a second input of a comparator to generate a number of output signals from the comparator, wherein each output signal has one of a first polarity and a second polarity. The method may further include in response to each of the number of output signals being the first polarity, applying, via a strobe, an external offset voltage having the second polarity to the comparator to generate a second number of output signals. Further, the method may include in response to each of the second number of output signals being the same polarity, identifying the comparator as a reliable comparator.

Systems, methods, and apparatuses for magnetic field sensors with self-test include a detection circuit to detect speed and direction of a target. One or more circuits to test accuracy of the detected speed and direction may be included. One or more circuits to test accuracy of an oscillator may also be included. One or more circuits to test the accuracy of an analog-to-digital converter may also be included. Additionally, one or more IDDQ and/or built-in-self test (BIST) circuits may be included.

A method determines the frequency of an alternating input signal includes storing the input signal, sampling the input signal at a first sampling frequency, a first calculation and a first angular comparison of two phasors representing the input signal at two respective instants, as a function of the input signal sampled at the first sampling frequency, estimating the frequency of the input signal, and searching for a modification of frequency of the input signal. When a modification is detected the method includes, determining a second sampling frequency, sampling the stored input signal with the second sampling frequency, a second calculation and a second angular comparison of two phasors representing the input signal, at two respective instants, as a function of the input signal sampled at the second sampling frequency and of the stored input signal sampled at the second sampling frequency, and estimating the frequency of the input signal.

A C/N ratio detection circuit includes a voltage detector, an averaging section, a time variation range calculator, and a C/N ratio calculator. The voltage detector measures an input voltage of a signal. The averaging section calculates an average of the input voltage over a predetermined time. The time variation range calculator calculates a time variation range of the input voltage over the predetermined time. The C/N ratio calculator calculates a C/N ratio of the signal by using the average and time variation range of the input voltage.

Technologies directed to determine whether a frequency of a clock signal is outside a specified frequency range are described. One integrated circuit includes a signal generator circuit, a voltage divider circuit, and digital logic circuitry. The signal generator circuit generates phase signals from a clock signal. The voltage divider circuit converts a frequency of the clock signal to a voltage representing the frequency. The voltage divider circuit includes a first resistor and a first switched-capacitor structure to receive the phase signals. An average resistance of the first switched-capacitor structure is inversely proportional to the frequency of the clock signal. The digital logic circuitry can determine, using the voltage, whether the frequency is outside of a specified frequency range, and output an indication responsive to the frequency being outside the specified frequency range.

The present invention relates to a wireless power transmission system for detecting an optimal resonance frequency and a method of detecting an optimal resonance frequency using the same, and provides a system and method for detecting an optimal resonance frequency for maximum wireless power transmission, the system and the method enabling an optimal resonance frequency for maximum power transmission to be effectively and quickly detected and enabling an optimal resonance frequency to be more precisely and accurately detected and found, even if a system usage situation changes, such as when a power transmission distance changes, in a wireless power transmission system of a magnetic resonant coupling scheme.

A detection device includes: a frequency property acquisition unit that acquires a frequency property when an alternating-current signal is input to at least two conductive bodies provided on a fiber sheet; and a detection signal output unit that outputs a detection signal when the frequency property acquisition unit acquires a predetermined frequency property.