A system for analyzing a passive network is provided, the system being configured to extend the frequency band with the interpolation function of the low frequency band and the extrapolation function of the high frequency band for S-parameters with limited measurement band, adjust the propagation delay time for the band-extended S-parameter to derive the final band-extended S-parameter, and analyze the time response of the passive network on the basis of the output voltage waveform estimated by performing convolution on the impulse response to the derived final band-extended S-parameter and the input voltage waveform of the passive network, thereby improving the time response performance of the passive network without a complex circuit conversion process, and making it possible to be capable of lightweight structures. Furthermore, it is possible to improve the accuracy of the impulse response by adjusting the propagation delay time removed from the band-limited S-parameter.

A test circuit includes an oscillator configured to generate an oscillation signal, a device-under-test (DUT) configured to output an AC signal based on the oscillation signal, a first detection circuit configured to generate a first DC voltage having a first value based on the oscillation signal, and a second detection circuit configured to generate a second DC voltage having a second value based on the AC signal.

A radio frequency (RF) based waveguide health monitoring system is disclosed. The system employs an RF transmitter for launching a probe RF waveform into a waveguide. Reflections, etc., from the interior of the waveguide of the probe RF waveform create a signature RF waveform, with a health RF receiver receiving this resultant signature RF waveform. A health processing system analyzes the signature RF waveform, and when it detects a change indicative of a deformation of the waveguide, generates a warning signal. This change may be due to bends, flexes, vibrations (or changes in vibrations), or separations of the waveguide. The system may have low frequency, high frequency, or high frequency imaging modes. The system may employ a high-power probe RF waveform, thereby enabling a wireless charging system with power RF receivers located along the length of the waveguide providing additional functionality.

The present exemplary embodiments provide a signal detection circuit and a sensor which improve a quality factor of a resonator by modeling an initial state of the resonator using an attenuator and a phase shifter which are modeling paths and significantly change a transmission coefficient of the resonator even with a small variation of an object to be measured.

A reflectometer may include two directional couplers in a parallel configuration, sharing the same section of a signal line or through-line. For example, two directional couplers may be disposed across from each other on opposite sides of the shared through-line. One of the directional couplers may couple, to a first port of the reflectometer, a portion of the signal power of a first signal flowing from the first end of the shared through-line to the second end of the shared through-line, and the other directional coupler may couple, to a second port of the reflectometer, a portion of the signal power of a second signal flowing from the second end of the shared through-line to the first end of the shared through-line. The reflectometer benefits from reduced size and signal loss with respect to reflectometers having a serial configuration. When used in vector network analyzer (VNA) systems, this results in higher output power and higher dynamic range of the VNA.

A reflectometer may include two directional couplers in a parallel configuration, sharing the same section of a signal line or through-line. For example, two directional couplers may be disposed across from each other on opposite sides of the shared through-line. One of the directional couplers may couple, to a first port of the reflectometer, a portion of the signal power of a first signal flowing from the first end of the shared through-line to the second end of the shared through-line, and the other directional coupler may couple, to a second port of the reflectometer, a portion of the signal power of a second signal flowing from the second end of the shared through-line to the first end of the shared through-line. The reflectometer benefits from reduced size and signal loss with respect to reflectometers having a serial configuration. When used in vector network analyzer (VNA) systems, this results in higher output power and higher dynamic range of the VNA.

A measuring device includes a first measuring port connected to an optical interface which can be connected to an optical input or output of a device under test (DUT). The device includes a second measuring port which can be connected to a radio frequency (RF) input or output of the DUT. The optical interface is connected to the optical input of the DUT and the second measuring port is connected to the RF output of the DUT. The first measuring port generates an analog measuring signal and provides it to the optical interface. The optical interface generates an optical measuring signal based on the analog measuring signal and provides it to the optical input of the DUT. The second measuring port receives an analog measuring signal generated by the DUT based on the optical measuring signal. The processor determines S-parameters of the DUT based on the two analog measuring signals.

A system may include an array of sensor elements, the array of sensor elements each comprising a first type of passive reactive element, a second type of passive reactive element electrically coupled to the array of sensor elements, a driver configured to drive the array of sensor elements and the second type of passive reactive element, and control circuitry configured to control enabling and disabling of individual sensor elements of the array of sensor elements to ensure no more than one of the array of sensor elements is enabled at a time such that when one of the array of sensor elements is enabled, the one of the array of sensor elements and the second type of passive reactive element together operate as a resonant sensor.

A system may include an array of sensor elements, the array of sensor elements each comprising a first type of passive reactive element, a second type of passive reactive element electrically coupled to the array of sensor elements, a driver configured to drive the array of sensor elements and the second type of passive reactive element, and control circuitry configured to control enabling and disabling of individual sensor elements of the array of sensor elements to ensure no more than one of the array of sensor elements is enabled at a time such that when one of the array of sensor elements is enabled, the one of the array of sensor elements and the second type of passive reactive element together operate as a resonant sensor.

A calibration apparatus calibrates cross-frequency phases of large-signal network analyzer measurements and includes: a signal generator; a vector network analyzer that includes couplers and receivers that receive the calibration signal and the reference multitone signal from the signal generator; a calibration receiver that receives a calibration signal from the vector network analyzer and produces a digitized calibration temporal signal from the calibration signal; and a signal processor in communication with the signal generator and the vector network analyzer and that: receives the reference digitized signal from the reference receiver; receives the forward digitized signal from the forward coupled receiver; receives the reverse digitized signal from the reverse coupled receiver; receives the digitized calibration temporal signal from the calibration receiver; and produces a calibration factor from the reference digitized signal, the forward digitized signal, the reverse digitized signal, and the digitized calibration temporal signal.