149 results about "Frequency dependence" patented technology

This disclosure demonstrates a new class of Ultra-Wide Band (UWB) AMC with very large fractional bandwidth (>100%) even at lower frequencies (<1 GHz). This new UWB AMC is enabled by recognizing that any AMC must be an antenna in order to accept the incident radiation into the circuit. Therefore, by using UWB antenna design features, one can make wide band AMCs. Additionally, by manipulation of the UWB AMC element design, a 1/frequency dependence can be obtained for instantiating the benefits of a quarter wave reflection over a large UWB bandwidth with a single physical thickness.

A nanoparticle sensor is capable of detecting and recognizing single nanoparticles in an aqueous environment. Such sensor may find applications in broad areas of science and technology, from the analysis of diesel engine emissions to the detection of biological warfare agents. Particle detection is based on interferometric detection of multi-color light, scattered by the particle. On the fundamental level, the detected signal has a weaker dependence on particle size (ÿ R³), compared to standard detection methods (ÿ R⁶). This leads to a significantly larger signal-to-noise ratio for smaller particles. By using a multi-color or white excitation light, particle dielectric properties are probed at different frequencies. This scheme samples the frequency dependence of the particle's polarizability thereby making it possible to predict the composition of the particle material. The detection scheme also employs a heterodyne or pseudoheterodyne detection configuration, which allows it to reduce or eliminate noise contribution from phase variations, which appear in any interferometric measurements.

The purely bound electromagnetic modes of propagation supported by symmetric waveguide structures comprised of a thin lossy metal film of finite width embedded in an infinite homogeneous dielectric have been characterized at optical wavelengths. The modes supported are divided into four families depending on the symmetry of their fields. In addition to the four fundamental modes that exist, numerous higher order ones are supported as well. A nomenclature suitable for identifying all modes is discussed. The dispersion of the modes with film thickness and width has been assessed and the effects of varying the background permittivity on the characteristics of the modes determined. The frequency dependency of one of the modes has been investigated. The higher order modes have a cut-off width, below which they are no longer propagated and some of the modes have a cut-off thickness.

An electrical connector with improved crosstalk compensation is disclosed. By including at least one coupling with a different frequency dependency than other couplings in the connector, crosstalk compensation performance is improved over a greater frequency range. The different frequency dependency may, for example, be used to compensate for phase shifts caused by distances between compensation circuitry and the plug/jack interface. Embodiments for decreasing these distances are also disclosed.

A frequency domain transforming section 2 transforms mixed signals observed by multiple sensors into mixed signals in the frequency domain, a complex vector generating section 3 generates a complex vector by using the frequency-domain mixed signals, a normalizing section 4 generates a normalized vector excluding frequency dependence of the complex vector, and a clustering section 5 clusters the normalized vectors to generate clusters. Then, a separated signal generating section 6 generates separated signals in the frequency domain by using information about the clusters and a time domain transforming section 7 transforms the separated signals in the frequency domain into separated signals in the time domain.

A calibration system and method is described to continuously measure and adjust several parameters of a magnetic imaging array. One or more non-target magnetic field source(s) are used to generate a well-defined and distinguishable spatial magnetic field distribution. The magnetic imaging array is used to measure the strength of the non-target magnetic fields and the information is used to calibrate several parameters of the array, such as, but not limited to, effective magnetometer positions and orientations, gains and their frequency dependence, bandwidth, and linearity. The calibration can happen continuously or periodically, while the imaging array is operating to create magnetic field images, if the modulation frequencies for calibration are outside the frequency window of interest.

Many reservoirs of interest include heavy oil. In such reservoirs, parti at normal temperatures, many instruments commonly used for formation evaluation may not be able to distinguish between heavy oil and bound water in the formation. Passive or active heating is used to elevate the temperature of the fluids in the formation. At elevated temperatures, distinguishing between heavy oil and bound water is easier. Of particular interest is the increase in the resolvability of the transverse relaxation time T2 of NMR spin echo measurements. Additionally, the dielectric constant and the loss tangents of water and heavy oil show different temperature and frequency dependence.

A reservoir fluid identification method based on pore fluid parameter frequency dependence inversion is disclosed. The method comprises the following steps of carrying out amplitude preservation, denoising and offset processing on pre-stack seismic data; carrying out different-angle stack to acquire different-angle-stack seismic data of at least three angles; establishing a pore fluid parameter and a shear modulus model, extracting an angle wavelet and carrying out wavelet multi-scale frequency division processing on the different angle stack seismic data; carrying out frequency dependence attribute inversion of the pore fluid parameter; and according to a pore fluid parameter frequency dependence attribute evolution value, determining a reservoir fluid development situation. By using the method, received seismic information is used and a deceptive problem in conventional fluid identification can be well solved; a sensibility of a dependence inversion attribute of a pore-fluid sensitive parameter to a reservoir fluid is high and identification precision to the fluid is high; an Bayesian inversion theory is used to carry out inversion so that stability and reliability are high.

It is intended to recognize the state of charge or depth of discharge of the battery more accurately than conventional technologies and to recognize health of a battery appropriately. Complex impedance between positive and negative electrodes of the battery is determined at a plurality of frequencies, and the state of charge or depth of discharge of the battery is estimated by comparing frequency dependency of Warburg impedance of the determined complex impedances with frequency dependency of Warburg impedance corresponding to a known state of charge or depth of discharge of the battery. Similarly, complex impedance is determined, and the health of the battery is evaluated by using the real part of the complex impedance at a point where the imaginary part of the complex impedance is zero on a line obtained by extending a part, which indicates frequency dependency of Warburg impedance, of a complex impedance characteristic curve representing a correlation relationship between the real and imaginary parts of the determined complex impedance.

Objective measurement methods and devices for predicting perceptual quality of speech signals degraded in speech processing/transporting systems have unreliable prediction results in cases where the degraded and reference signals show in between severe timbre differences. Improvement is achieved by applying a partial compensation step within in a signal processing stage using a frequency dependently clipped compensation factor for compensating power differences between the degraded and reference signals in the frequency domain. Preferably clipping values for clipping the compensation factor have larger frequency-dependency in a range of low frequencies with respect to a centre frequency of the human auditory system, than in a range of high frequencies.

The variable gain amplifier includes a bias circuit (BC) 1, a matching circuit (MC) 2, a variable gain resistive feedback amplifier (FA) 3 and an output follower (EA) 4. The resistance values of the load resistance Rc and feedback resistance Rf are changed in cooperation. In a case of making the load resistance Rc a high resistance to set the low noise amplifier to a high gain, the feedback resistance Rf is also made a high resistance, the feedback time constant τfb(c1)≈2π·RfCbe/(1+gmRc) of the closed loop of the resistive negative feedback amplifier 3 becomes substantially constant, and then the amplifier has a gain small in frequency dependency over a wide bandwidth. In a case of making the load resistance Rc a low resistance to set the low noise amplifier to a low gain, the feedback resistance Rf is also made a low resistance. The feedback resistance Rf with the low resistance increases the negative feedback quantity, and thus the amplifier is set to a low gain. Also, the load resistance Rc is made a low resistance, and the feedback time constant τfb(c1) becomes substantially constant. The gain is not lowered further in a high frequency region.

A non-contact apparatus and method for measuring of the leakage current and capacitance of p-n junctions in test structures within scribe lanes of IC product wafers is disclosed. The apparatus has a light source optically coupled with a fiber to a transparent electrode at the end of the fiber, which is brought close to the p-n junction under test. The ac signal generated from the test p-n junction is captured by this transparent and conducting coating electrode. The leakage current of a test p-n junction is determined using the frequency dependence of junction photo-voltage signal and reference signals from a p-n junction with low leakage current and known capacitance.

A system and method is provided for reducing the sensitivity of the rotation rate measurement to the frequency dependence of the feedback modulator. Specifically, the system and method uses a minimal bias switching technique to reduce rate errors associated with the low frequency 2π resets in a closed loop fiber optic gyroscope with a phase modulator with a different phase shift associated to low and high frequencies. In general, the minimal bias switching technique reduces the low frequency components of the feedback modulation drive by increasing the frequency of the 2π resets. As a consequence, the system and method reduces the low frequency component of the feedback modulator drive to avoid errors that occur with the low frequency 2π resets.

Method comprising obtaining an NMR measurement from a sample wherein an ultra-low field NMR system probes the sample and produces the NMR measurement and wherein a sampling temperature, prepolarizing field, and measurement field are known; detecting the NMR measurement by means of inductive coils; analyzing the NMR measurement to obtain at least one measurement feature wherein the measurement feature comprises T1, T2, T1ρ, or the frequency dependence thereof; and, searching for the at least one measurement feature within a database comprising NMR reference data for at least one material to determine if the sample comprises a material of interest.

The floating memristor emulator is based on a circuit implementation that uses grounded capacitors and CFOAs in addition to combinations of diodes and resistors to provide the required nonlinearity and time constants. This circuit results in low power consumption, cost reduction and ease of implementation because it avoids the use of multipliers, ADCs and RDACs. The present circuit is used in an FM demodulator, which exploits the frequency-dependence of the memristance. Successful use in the FM demodulator confirmed the functionality of the present floating memristor emulator circuit.