2558results about "Frequency measurement arrangement" patented technology

High frequency interconnect structures, electronic assemblies that utilize high frequency interconnect structures, and methods of operating the same. The high frequency interconnect structures include a plurality of dielectric waveguides and are configured to communicatively connect a plurality of transmitters with a plurality of receivers and to convey a plurality of signals therebetween. The plurality of signals may include a plurality of electromagnetic waves and may have a frequency of at least 200 GHz. The high frequency interconnect structures further may be configured to decrease a potential for crosstalk between a first signal that is conveyed by a first dielectric waveguide of the plurality of dielectric waveguides and a second signal that is conveyed by a second dielectric waveguide of the plurality of dielectric waveguides, such as through control of a passband of the first dielectric waveguide relative to the second dielectric waveguide and / or the use of a crosstalk mitigation structure.

Low cost millimeter wave imagers using two-dimensional focal plane arrays based on backward tunneling diode (BTD) detectors. Two-dimensional focal arrays of BTD detectors are used as focal plane arrays in imagers. High responsivity of BTD detectors near zero bias results in low noise detectors that alleviate the need for expensive and heat generating low noise amplifiers or Dicke switches in the imager. BTD detectors are installed on a printed circuit board using flip chip packaging technology and horn antennas direct the waves toward the flip chip including the BTD detectors. The assembly of the horn antennas, flip chips, printed circuit board substrate, and interconnects together work as an imaging sensor. Corrugated surfaces of the components prevent re-radiation of the incident waves.

In a gap-mode waveguide embodiment, an interior gap in a tubular waveguide principally condenses a dominant gap mode near the interior gap, and an absorber dissipates electromagnetic energy away from the gap mode. In this manner, the gap mode may dissipate relatively little power in the absorber compared to other modes and propagate with lesser attenuation than all other modes. A gap mode launched into a gap-mode waveguide may provide for low-loss, low-dispersion propagation of signals over a bandwidth including a multimode range of the waveguide. Gap-mode waveguide embodiments of various forms may be used to build guided-wave circuits covering broad bandwidths extending to terahertz frequencies.

The subject matter of the present invention is a method for monitoring a photovoltaic generator (1) for generating current with a number of solar cells connected between two external connections by repeated feeding of a current with a frequency spectrum into the generator current circuit, detecting thereby a respective frequency response in the frequency spectrum with the supplied current as the input variable and an electric variable of the generator as the output variable, and detecting a change in the frequency response for monitoring the photovoltaic generator (1) in the event of a change during repeated feeding.

The invention provides a method of apparatus for testing circuit boards which does not require any inner wide power plane so as to detect an open circuit defect and / or a short circuit defect in a conductor path network formed in the circuit board quickly and accurately. An apparatus for testing a circuit board according to the present invention includes a transmission unit (2) for transmitting electromagnetic (radio) wave signal by way of an antenna (1) to a circuit board (3) to be tested, a detecting unit (3) for detecting signal received by a conductor path (4) of the circuit board (3) by using the conductor path (4) as a receiving antenna, and compare unit (8) for determining whether or not there is an open circuit defect or a short circuit defect in the conductor path (4) by comparing the detected signal with reference data of corresponding to a conductor path not including any defect.

A system incorporating the subject disclosure may include, for example, a method including determining, by a communication device comprising a processor, a usage state of the communication device. The communication device includes selectable antennas, and the usage state includes an orientation of the communication device. The method also includes selecting a set of antennas according to the usage state, and obtaining an antenna gain pattern for an antenna in the selected set of antennas. The method further includes evaluating an expected performance of an antenna configuration corresponding to the selected set of antennas, relative to a performance of an existing antenna configuration. The method also includes initiating usage of the antenna configuration in accordance with improved performance relative to the existing antenna configuration. The antenna configuration comprises a polarization configuration, and the selected set of antennas comprises elements in different planes. Other embodiments are disclosed.

An integrated circuit includes a plurality of processing stages each including processing logic 1014, a non-delayed signal-capture element 1016, a delayed signal-capture element 1018 and a comparator 1024. The non-delayed signal-capture element 1016 captures an output from the processing logic 1014 at a non-delayed capture time. At a later delayed capture time, the delayed signal-capture element 1018 also captures a value from the processing logic 1014. An error detection circuit 1026 and error correction circuit 1028 detect and correct random errors in the delayed value and supplies an error-checked delayed value to the comparator 1024. The comparator 1024 compares the error-checked delayed value and the non-delayed value and if they are not equal this indicates that the non-delayed value was captured too soon and should be replaced by the error-checked delayed value. The non-delayed value is passed to the subsequent processing stage immediately following its capture and accordingly error recovery mechanisms are used to suppress the erroneous processing which has occurred by the subsequent processing stages, such as gating the clock and allowing the correct signal values to propagate through the subsequent processing logic before restarting the clock. The operating parameters of the integrated circuit, such as the clock frequency, the operating voltage, the body biased voltage, temperature and the like are adjusted so as to maintain a finite non-zero error rate in a manner that increases overall performance.

The subject matter of the present invention is a method for monitoring a photovoltaic generator (1) for generating current with a number of solar cells connected between two external connections by repeated feeding of a current with a frequency spectrum into the generator current circuit, detecting thereby a respective frequency response in the frequency spectrum with the supplied current as the input variable and an electric variable of the generator as the output variable, and detecting a change in the frequency response for monitoring the photovoltaic generator (1) in the event of a change during repeated feeding.

The present invention provides for an improved scanning process having microwave arrays comprised of microwave transmitters in radiographic alignment with microwave receivers. The microwave array emits controllably directed microwave radiation toward an object under inspection. The object under inspection absorbs radiation in a manner dependent upon its metal content. The microwave radiation absorption can be used to generate a measurement of metal content. The measurement, in turn, can be used to calculate at least a portion of the volume and shape of the object under inspection. The measurement can be compared to a plurality of predefined threats. The microwave screening system can be used in combination with other screening technologies, such as NQR-based screening, X-ray transmission based screening, X-ray scattered based screening, or Computed Tomography based screening.

The invention discloses a power signal frequency detection method and a power signal frequency detection system based on phase modulation. The method comprises the steps: sampling a power signal according to preset signal time span and preset sampling frequency, so as to obtain an input signal sequence; measuring the frequency of the input signal sequence, so as to obtain the initial frequency of the power signal, and subtracting the input signal sequence and the plus or minus 1 Pi phase-shift sequence of the input signal sequence by using the initial frequency as reference frequency, so as to obtain two phase modulation sequences of which phases change along with the input signal frequency; respectively mixing, filtering and integrating the two phase modulation sequences, so as to obtain the phases of the two phase modulation phases for frequency measurement. By implementing the power signal frequency detection method and the power signal frequency detection system, frequency measurement results with higher accuracy can be obtained.

An integrated infrared and millimeter-wave monolithic focal plane sensor array having a substrate upon which an integrated array of infrared sensors and mm-wave sensors are provided at a first planar level on the same side of the substrate, and a planar antenna for receiving incident millimeter-wave radiation located at a second planar level located between the integrated array of sensors and the surface of the substrates for coupling the mm-wave radiation field to the mm-wave sensor. The antenna receiver of electromagnetic radiation, in one embodiment, is an antenna having a crossed bowtie configuration which efficiently couples the radiation field to the mm-wave sensor. The invention also is directed to a method of fabricating such a radiation sensor.

Methods and systems of detecting one or more characteristics of a load are disclosed. One or more characteristics of a first signal may be detected at the output of a Radio Frequency (RF) power generator. The first signal may have a fundamental frequency. The one or more characteristics of the first signal may be sampled at a sampling frequency to produce a digital sampled signal. The sampling frequency may be determined based on a function of the fundamental frequency of the first signal. One or more characteristics of a load in communication with the RF power generator may then be determined from the digital sampled signal.

The invention discloses a sinusoidal parameter measurement method and system of a power signal. The method comprises the following steps: performing preliminary measurement on fundamental wave frequency of a sampling data sequence to acquire preliminary fundamental wave frequency and multiplying a cosine function and a sine function of the preliminary fundamental wave frequency serving as the reference frequency by the sampling data sequence respectively to generate a real vector sequence and an imaginary vector sequence; performing digital filtering on the real vector sequence and the imaginary vector sequence to generate a real vector filter sequence and an imaginary vector filter sequence, and further integrating to generate a real vector integral value and an imaginary vector integral value; converting the real vector integral value and the imaginary vector integral value into corresponding sinusoidal parameters according to a preset sinusoidal parameter conversion rule. By implementing the method and the system, mixed frequency interference elements in the real vector sequence and the imaginary vector sequence can be inhibited to generate high-precision real vector and imaginary vector sequence integral values so as to finally obtain the sinusoidal parameters with higher precision.

The invention provides a test system and a test method. The testing system comprises a test fixture, a test device and a differential tunable matching network, wherein the test fixture is provided with a bearing structure for loading a chip to be tested and a test port electrically connected to the chip to be tested; the test device comprises a radio frequency signal source, a receiving unit and a processing and display unit; the radio frequency signal source is provided with at least one radio frequency test port; the receiving unit is used for at least receiving a reflected signal and a transmitted signal which are generated after a radio frequency signal passes through the chip to be tested; the processing and display unit is used for processing the received radio frequency signal and displaying the processed signal; and the differential tunable matching network is provided with an input port and a differential output port and is used for tuning the impedance of a load end including the chip to be tested to make the impedance of the load end matched with the internal resistance of the test device and providing the test device to measure the characteristic of the chip to be detected in the test fixture. Compared with the prior art, the invention has the advantages that: the differential tunable matching network is provided for realizing impedance matching, the test system and the test method are easy and convenient to operate, and a more accurate test result can be acquired.

An integrated circuit (IC) is disclosed having circuitry arranged in a plurality of columns. A column in the IC is essentially a series of aligned circuit elements of the same type that extends from a first edge of the IC to a second edge. In addition there may be a center column having circuit elements of different types.

A method for making a light-emitting diode, which including the steps of: providing a substrate having at least one recessed portion on one main surface and growing a first nitride-based III-V group compound semiconductor layer through a state of making a triangle in section having a bottom surface of the recessed portion as a base thereby burying the recessed portion; laterally growing a second nitride-based III-V group compound semiconductor layer from the first nitride-based III-V group compound semiconductor layer over the substrate; and successively growing a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type on the second nitride-based III-V group compound semiconductor layer.

Apparatus for determining the frequency of an ac power signal, includes sensing circuitry to sense the ac signal. In a digital implementation of the invention, a double average of the samples is generated by a processor as the sum of the most recent sample, twice the next most recent sample plus the third most recent sample. The least mean square of a running window of the most recent double average signals is generated to avoid discontinuities at the zero crossings and to reduce the effects of noise. The frequency is determined from this least mean square value of the window of double average signals. As implemented in a protective relay, a trip signal is generated if the frequency is out of limits.

A PIM measurement circuit enables making forward and reverse PIM measurements on any 1 port (reflection) or 2 port (transmission) device with the ability to determine in distance where individual PIM impairments are located as well as their magnitude. The PIM measurement circuit includes two frequency sources that are provided through a combiner for a CW characterization of the PIM circuit. To enable distance determination, an FM measurement is created by using a saw tooth offset sweep generator attached to one of the two frequency sources. With downconversion and processing of signals from the PIM impairments, the FM signal provides a frequency variation that is converted using a Fourier transform or spectrum analysis for separation of frequencies, enabling determination of the distance of the PIM sources as well as their magnitudes.

A near field probe for testing installed components of an electromagnetic radiating system on a missile. The probe design comprises a diode antenna with a balun. The probe utilizes a dual diode arrangement which provides approximately twice the output voltage as the previous probe. The probe may then be placed further away from the radiating system under test.

The invention belongs to the technical field of digital signal processing, and provides a high-efficiency measurement method of a sinusoidal signal frequency in undersampling and an implementation device which can estimate parameters such as frequency and the like under the condition of undersampling and can finish precise frequency measurement. The invention adopts the technical scheme that traditional FFT spectrum analysis and all phase FFT spectrum analysis are adopted to obtain a peak value spectrum G (q) and a peak value spectrum Ga (q); a phase value is directly read from the peak valuespectrum to take the square of a G (q) modulus to obtain a power spectrum value Pg (q); after performing modulus division on Pg (q) and Ga (q), amplitude estimation is obtained to take the differenceof the phase value of G (q) and the phase value of g(q), and the difference divided by tau=(N-1) / 2 to obtain frequency offset estimation delta k; and finally delta k delta omega and q delta omega aresuperposed to obtain digital angular frequency estimation which directly serves as the phase estimation and the amplitude estimation of the measured signal. The invention is mainly used for undersampling measurement in digital signal processing.

The present invention relates to an electronic circuit for measuring small amounts of charge or small electrical currents. One embodiment of the present invention provides an electronic circuit for measuring current or charge that can be used with a variety of sensing media (including high impedance sensing media) that produce a signal by either charge or current production or induction in response to physical phenomena occurring within the sensing media. In another embodiment, the voltage level (bias) of either the sensing or reference electrode can be switched relative to the other upon receipt of a triggering pulse. This changes the polarity of the electric field to cause charge of the opposite polarity to be driven to the sensing electrode, thereby eliminating the need to electrically connect a discharge path to the sensing electrode to clear the charge accumulated at the sensing electrode. This can be supplemented by capacitively coupling a compensation signal to the sensing electrode to cause the amplifier output signal to lessen in magnitude below a threshold level that permits additional charge or current measurements of the same polarity before performing bias reversal. Alternately or in combination with bias reversal and capacitive compensation, sensor performance can be improved by minimizing inaccuracies caused by leakage currents or current drawn from the sensor. Other methods of reducing leakage currents that can be used alone or in combination with the aforementioned features include the use of guard rings, physical switches or relays, the controlled creation of charges or currents of a specific polarity in a specific region of the sensing medium, controlled leakage over the surface of an insulator, and controlling the environment in which the circuit operates.

The present invention relates to current measurement apparatus 100. The current measurement apparatus 100 comprises a measurement arrangement 110, 114 which is configured to be disposed in relation to a load 108 which draws a current signal, the measurement arrangement being operative when so disposed to measure the load drawn current signal. The current measurement apparatus 100 also comprises a signal source 112 which is operative to apply a reference input signal to the measurement arrangement 110, 114 whereby an output signal from the measurement arrangement comprises a load output signal corresponding to the load drawn current signal and a reference output signal corresponding to the reference input signal. The current measurement apparatus 100 further comprises processing apparatus 116 which is operative to receive the output signal and to make a determination in dependence on the reference output signal and the load output signal, the determination being in respect of at least one of the load drawn current signal and electrical power consumed by the load.

Methods and systems of detecting one or more characteristics of a load are disclosed. One or more characteristics of a first signal may be detected at the output of a Radio Frequency (RF) power generator. The first signal may have a fundamental frequency. The one or more characteristics of the first signal may be sampled at a sampling frequency to produce a digital sampled signal. The sampling frequency may be determined based on a function of the fundamental frequency of the first signal. One or more characteristics of a load in communication with the RF power generator may then be determined from the digital sampled signal.

A power supply circuit for operating high-efficiency lighting devices from a thyristor-controlled dimmer determines the dimming value, i.e., the dimmer duty factor by periodically probing the dimmer output. A minimum conductance is applied across the output of the dimmer during probing intervals that begin at the turn-on time of the dimmer and last until enough information has been gathered to correctly predict a next zero crossing of the AC line voltage that supplies the input of the dimmer. The dimming value is determined from the time interval between the predicted zero-crossing and a next turn-on time of the dimmer. The probing can be performed at intervals of an odd number of half-cycles of the AC line frequency so that a DC offset is not introduced within internal timing circuits of the dimmer. The AC line frequency can also be determined from a time interval between the predicted zero crossings.

The invention discloses a method and a system for orthogonal modulation of power signals. The method comprises the following steps: acquiring an initial sequence length and an initial sequence according to a frequency lower limit, a preset sampling frequency and an initially set integer signal cycle number of a power signal; acquiring a reference frequency according to the initial sequence, and further acquiring a unit cycle sequence length and a preset sequence length; acquiring first forward and reverse sequences according to a preset sequence starting point and the preset sequence length; generating first real-frequency and imaginary-frequency vector sequences and second real-frequency and imaginary-frequency vector sequences according to the first forward and reverse sequences; converting obtained first and second phases into a first forward sequence average initial phase; obtaining a new preset sequence starting point according to the average initial phase; and obtaining a cosine function modulation sequence and a sine function modulation sequence according to second forward and reverse sequences obtained from the initial sequence. By adopting the method and the system of the invention, an orthogonal modulation sequence with consistent amplitude height can be obtained, and the accuracy and anti-jamming performance of sinusoidal parameter calculation are improved.

The high-accuracy synchronous phasor measurement method belongs to the field of automatic measurement technology of power system. On the basis of spaced sampling circulation DFT, when the system frequency is deviated from rated frequency, the influence of frequency deviation can be calculated to make the frequency and phasor measurement have higher accuracy. The field tests show that when the sampling frequency is 4800 Hz and phasor correction calculation frequency is 200 Hz, its static accuracy indexes are: phasor magnitude error is less than 0.5%, phasor phase angle error is less than 1 deg.C and frequency calculation error is less than 0.01 Hz, and its dynamic accuracy indexes are: phosar magnitude error is less than 1%, phasor phase angle error is less than 1 deg. and frequency calculation error is less than 0.01 Hz.

A cell that can be used as a dynamic memory cell for storing data used in programming a field programmable gate array (FPGA) is disclosed. The cell comprises a select transistor having a gate, a source, and a drain, the gate connected to said write bitline, the source connected to a floating point node, and the drain connected to a row wordline. A sense device determines the data stored on the floating point node. Finally, switch that is controlled by the floating point node is provided.

A device for detecting and counting coughing events is provided. In one embodiment a sensor for sensing and transducing low frequency and high frequency mechanical vibrations, sends signals to a coincidence detector that determines if high and low signals coincide. In another embodiment, ultrasonic energy is introduced to the trachea and if Doppler shift in frequency is detected, association is made to a coughing event. In another embodiment a change in the impedance of the neck is considered associated with coughing event if correlated over time with a specific mechanical frequency sensed.

A power distribution monitoring system is provided that can include a number of features. The system can include a plurality of monitoring devices configured to attach to individual conductors on a power grid distribution network. In some embodiments, a monitoring device is disposed on each conductor of a three-phase network. The monitoring devices can be configured to measure and monitor, among other things, current and electric-field on the conductors. Methods of calibrating the monitoring devices to accurately measure electric-field are also provided. In one embodiment, a first monitoring device on a first conductor can transmit a calibration pulse to a second monitoring device on a second conductor. The second monitoring device can determine a degradation of the calibration pulse, and use that degradation to calibrate electric-field measurements around the conductor.

The invention discloses a microwave sensor based on an NV color center diamond. A diamond internally containing a Nitrogen-Vacancy color center is adopted as a sensitive element, electronic energy level stimulation is achieved through lasers, an additionally-arranged static magnetic field is scanned, and the microwave frequency and the microwave intensity are measured through fluorescence intensity detection. Dependency of electronic rabi-flopping of the NV color center in the diamond on the external microwave magnetic field is brought into play, high theoretical accuracy and good stability are achieved, the microwave sensor has the advantages of being small in size, low in cost, high in accuracy, large in temperature range, simple in operation condition and the like and rotates on the basis of solid atoms, and the microwave sensor can serve in all the fields with the requirements for the low-cost high-accuracy microwave frequency and intensity detection in the future.