62 results about "Dephasing" patented technology

A 2-D three-frequency diphase measuring method based on colored- structure light includes preparing three gratings by complexing different three primary color sine light with three the same frequencies, projecting said gratings on object to be measured, utilizing two the same CCD vide cameras to make shooting for obtaining 24 pieces of pictures, dephasing said pictures to obtain phase values at X and Y direction on each pixel pf each picture and matching two phase values for calculating out 3-D coordinate of each point.

The invention discloses an eliminator of a self-interference signal, which comprises a dephasing attenuation processing module and a signal elimination processing module, wherein the dephasing attenuation processing module receives a first signal from the outside to carry out attenuation and dephasing processing so acquire an estimated self-interference signal, and the signal elimination processing module receives a second signal from the outside and the estimated self-interference signal from the dephasing attenuation processing module and eliminates the estimated self-interfering signal in the second signal. The invention also discloses an elimination method of the self-interference signal, which comprises the following steps: first, the attenuation and dephasing processing is carried out to a sent signal to obtain the estimated self-interference signal; and second, the estimated self-interference signal is eliminated in the received signal. In addition, the invention also discloses an RFID read-write counter. The eliminator of the self-interference signal acquires the estimated self-interference signal and eliminates the estimated self-interference signal by the attenuation and dephasing processing of the sent signal so as to reduce the influence of the self-interference signal on receiving sensitivity.

The invention discloses an array antenna for generating microwave orbital angular momentum based on a phase gradient super-surface. The array antenna is formed by the arrangement of phase shift units (1), each phase shift unit (1) comprises a dielectric plate (3), a metal patch (4) is arranged on the surface of the dielectric plate (3), an upper hole (5) is formed in the middle of the metal patch (4), a metal ground plate (6) is arranged at the bottom of the dielectric plate (3), a lower hole (7) is formed in the middle of the metal ground plate (6), and a metal pipe (8) is arranged at the middle of the dielectric plate (3) and communicates with the upper hole (5) and the lower hole (7). The array antenna has the characteristics of small size, light weight and low cost; meanwhile, the continuous control of the orbital angular momentum in phases of 0 to 2Pi is further achieved, and obvious vortex orbital angular momentum is generated; and moreover, the array antenna has an excellent reflection effect.

Contrast agents incorporating super-paramagnetic iron-oxide (SPIO) nanoparticles have shown promise as a means to visualize labeled cells using MRI. Labeled cells cause significant signal dephasing due to the magnetic field inhomogeneity induced in water molecules near the cell. With the resulting signal void as the means for detection, the particles are behaving as a negative contrast agent, which can suffer from partial-volume effects. Disclosed is a new method for imaging labeled cells with positive contrast. Spectrally-selective RF pulses are used to excite and refocus the off-resonance water surrounding the labeled cells so that only the fluid and tissue immediately adjacent to the labeled cells are visible in the image. Phantom, in vitro, and in vivo experiments show the feasibility of the new method. A significant linear correlation (r=0.87, p<0.005) between the estimated number of cells and the signal has been observed.

The invention relates to a substrate integrated waveguide multiple beam antenna based on the Lotman lens principle. A substrate integrated waveguide similar to a waveguide structure is realized through an upper layer metal copper-clad surface (1), a lower layer metal copper-clad surface (2) and metalized pylomes (4) on a medium substrate (3), and a multiple beam antenna is formed; the structure of the multiple beam antenna is divided into three parts that: the first part is a substrate integrated waveguide Lotman lens (53); the second part is a substrate integrated waveguide dephasing network (8); the third part is a radiation antenna array (91), wherein, the first part is directly cascaded with the second part; and the second part is directly cascaded with the third part. The antenna is suitable for a microwave millimeter wave beam shaping network and a multiple beam antenna feeder system; the substrate integrated waveguide multiple beam antenna formed by the antennas can be applied to a microwave millimeter wave multiple beam system and an intelligent antenna, and has the advantages of improving the quality of a communication channel, reducing the sending power, bit error rate and multipath interference, etc.

The invention relates to an inter-section phase-shift asymmetry six-phase permanent-magnetic straight servo motor, wherein it comprises two unit motors serially or parallel connected; the initial magnetic circuits of said two motors are independent; the section are distanced via non-conductive material; the relative windings or relative second axles of two unit motors are distanced via 2k pi+-90degree, while k is integer; the windings are asymmetry six-phase structure; their initial stages are mounted on movable platform and above the second stage of permanent magnet. The invention can restrain winding harmonic wave of synchronous straight motor, reduce driving power of each phase, and improve the stability of servo controller.

An anti-vibratory device with rotary compensation weights includes two sets of two identical rotors with respective eccentric compensation weights, the units being symmetrically disposed in relation to an axis of symmetry and the axes of rotation of the rotors being parallel between themselves and orthogonal in relation to the axis of symmetry; and a rotational drive system for the rotors. Advantageously, the device includes controllable mobile equipment carrying the drive system and being able to slide along the axis of symmetry in order to drive the dephasing of the rotors with eccentric compensation weights associated with the sets.

A system to control an asynchronous tri-phase motor where said system comprises: at least one filter directly coupled to the current of the Alternative Current (AC) line; a rectifier which rectifies the line current, a doubler which reduces the curl, elevates the voltage and delivers a voltage in Direct Current, a braking resistance which helps to dissipate energy when the system is in braking mode, a shunt resistance, which helps to measure the current which flows from the V-line between the doubler and the IGBT module, a source, which adapts the voltage which the microcontroller consumes and peripheries (operational amplifiers, detectors, etc.), a line regulator to remove curls and line noise, a microcontroller to process, admit and emit control signals, a potential module which emits a PWM train pulse with a frequency determined by the microcontroller towards the IGBT module when the microcontroller indicates such, an IGBT module, which receives the PWM pulse train adapting and coupling them to an H bridge, to thus allow the flow of high voltage in DC emanating from the doubler towards the electric motor, a retro-feeding line towards the microcontroller to measure current, a velocity detector coupled mechanically to the motor and which sends a signal or pulse train towards the microcontroller; as well as the acceleration or braking methods consistent in the measurement of the slip S of said tri-phase motor.

In a method and apparatus for acquiring magnetic resonance (MR) data, MR signals are acquired simultaneously from N slices of a subject with an SMS factor of S, the N slices respectively being at different positions from an isocenter of the data acquisition scanner, thereby causing said MR signals to be affected differently by Maxwell terms of magnetic fields that give said MR signals respective signal dephasings that are dependent on the distance of a respective slice from the isocenter. The SMS MR data acquisition sequence is executed with a spacing between each pair of adjacent slices being less than or equal to N/2S. A Maxwell correction algorithm is applied to the acquired k-space data by calculating Maxwell correction gradient moments at an average position between each pair of adjacent slices, thereby generating corrected k-space data wherein the signal dephasing of the MR signals from the N slices is reduced.

A stripline-style ferrite phase shifter based on LTCC technology belongs to the technology of the short-wave communication device. The whole phase shifter is composed of two-layer rectangle gyromagnetic ferrite substrates clamping two-layer rectangle ceramic dielectric substrates, two paralleled magnetizing current leads and one bending microstrip line used for dephasing are clipped by the two-layer ceramic dielectric substrates; the two sides of the ferrite substrates exceeding the ceramic dielectric substrates in width are communicated with each other and form an enclosed magnetic loop. When the device is working, a ring shape silver electrode on the surface of the ferrite substrates is earthed, the impulse magnetization current is exerted to magnetize the gyromagnetic ferrite loop by the magnetizing current leads, the gyromagnetic ferrite substrates are working in remanence state after getting rid of magnetizing current; microwave signal is connected between the two termination electrodes of the bending microstip lines used for dephasing, and non-reciprocal differential phase shift is generated. Compared with the existing phase shifter, the volume and quality of the phase shifter in the invention can be greatly reduced, which is in favor of realizing the integration of phase shifter, active/passive devices and components.

A method and magnetic resonance system for imaging a particle that is located in an examination subject with an imaging magnetic resonance measurement execute a gradient echo sequence in which at least two gradient echoes are acquired following a single excitation pulse, wherein the particle in an applied basic magnetic field causes a magnetic interference field. An RF pulse is radiated to generate a transverse magnetization from a magnetization appearing in the basic magnetic field. A first dephasing gradient is shifted to adjust a first dephasing of the transverse magnetization, and the first gradient echo is acquired. A second dephasing gradient is shifted to adjust a second dephasing of the transverse magnetization that is different than the first dephasing, and the second gradient echo is acquired. The two dephasing gradients are shifted such that a dephasing of the transverse magnetization caused by the interference field of the particle is at least partially compensated in a region around the particle or within the particle given the acquisition of at least one of the echoes.

The invention discloses a high-power intelligent quick-charge electric source system for an electric automobile and a control method. The high-power intelligent quick-charge electric source system comprises a three-phase AC input electric network, a high-power parallel connection dephasing full-bridge main circuit, a positive negative pulse generation circuit, a control circuit and a battery load, wherein the high-power parallel connection dephasing full-bridge main circuit is formed by parallel connection of two or more sets of dephasing full-bridge inverters; the control circuit comprises two or more sets of first control circuits and a second control circuit; the first control circuits are in one-to-one correspondence to the dephasing full-bridge inverters, and each of the first control circuits comprises a voltage current detecting module, a fault protecting module, a first DSP digital control module and an MOSFET driving module; and the second control circuit comprises a second DSP digital control module, an IGBT driving module, an STM32 man-machine interface module and a battery status judging module. The high-power parallel connection dephasing full-bridge main circuit disclosed by the invention has the characteristics of being high in output power, high in charge efficiency, quick in charge rate and high in reliability.

The invention relates to a Mach-Zundel type shearing waveform measuring system and a shearing waveform measuring method thereof. The system comprises an interference system consisting of an incident panel, an emission panel, a fixed seat, a first reflecting panel, a second reflecting panel, a third reflecting panel, a fourth reflecting panel, a first guide rail, a second guide rail, an imaging lens, an aperture and a CCD imaging instrument. An adjusting device for ensuring accuracy comprises an auto-collimation collimator tube, a first reflecting mirror, a laser collimating light source, a reference transmitting and reflecting mirror, a second reflecting mirror, a lens screen, a first pentaprism, and a second pentaprism. A control processing system comprises a piezo-electric controller and a computer processing system. The system and the method are suitable for measuring waveform with large aperture and under a diffraction limit, and particularly suitable for being used on a light source waveform with short coherent length. The system and the method can conduct dephasing processing, and are provided with an entire system for real-time adjustment and calibration.

The invention provides a quantum dialogue protocol with collective-dephasing noise resisting authentication based on logic Bell states. Through the protocol, mutual identity authentication and dialogue can be simultaneously achieved securely between two participators on a collective-dephasing noise channel, wherein information transmitted through a classical channel can be intercepted and modified. A secret key used for selecting a sample logic qubit measurement base is shared by the two participators secretly in advance. Bell state measurement, instead of four-qubit joint measurement, is adopted for decoding. The two participators share the initial state of the information logic Bell state by the aid of direct transmission of the auxiliary logic Bell state. In this way, information leakage is avoided. Acting attacks from Eve, man-in-the-middle attacks and modification attacks can all be detected, and besides Trojan attacks can be avoided naturally.

A magnetic resonance imaging apparatus includes an RF coil unit which generates RF pulses toward a subject, and which receives an MR signal from the subject. Gradient magnetic field coils generate a gradient magnetic field for slice selection, a gradient magnetic field for phase encoding and a gradient magnetic field for frequency encoding, respectively. An arithmetic unit generates image data on the basis of the MR signal, and a sequence controller controls phase encoding gradient magnetic field coils in order to generate flow pulses for dephasing or rephasing the MR spin of blood flow within the subject, in the same direction as that of the phase encoding gradient magnetic field.

In a method and magnetic resonance apparatus to determine a B0 field map describing the local deviation from a nominal Larmor frequency of the magnetic resonance apparatus, magnetic resonance data are acquired at at least two different dephasing times after an excitation, in measurements implemented at two different echo times whose difference forms a dephasing time, and a phase change used to determine the B0 field map is determined from a difference of phases measured at different echo times. The phase changes of different dephasing times are evaluated to at least partially reduce an ambiguity due to Nyquist phase wrapping. The measurements for different dephasing times are implemented at least in part with excitations that generate different excitation fields.

Here we present a solid-state spin sensor with enhanced sensitivity. The enhanced sensitivity is achieved by increasing the T₂* dephasing time of the color center defects within the solid-state spin sensor. The T₂* dephasing time extension is achieved by mitigating dipolar coupling between paramagnetic defects within the solid-state spin sensor. The mitigation of the dipolar coupling is achieved by applying a magic-angle-spinning magnetic field to the color center defects. This field is generated by driving a magnetic field generator (e.g., Helmholtz coils) with phase-shifted sinusoidal waveforms from current source impedance-matched to the magnetic field generator. The waveforms may oscillate (and the field may rotate) at a frequency based on the precession period of the color center defects to reduce color center defect dephasing and further enhance measurement sensitivity.

The invention provides a quantum dialogue protocol with collective-dephasing noise resisting robustness based on logic qubits and CNOT operation. A preparation party produces the logic qubits serving as a transmission state to resist collective-dephasing noise. The other party knows the initial preparation state of the logic qubits by the aid of the CNOT operation and acquires secret information of the preparation party through decoding with the help of a classic information sequence transmitted by the preparation party. The preparation party reads secret information of the other party by the aid of quantum secure direct communication. In this way, the risk of information leakage is effectively avoided. In the protocol, only single-photon measurement is required for quantum measurement. Compared with a noise-resistant quantum dialogue protocol in the past, the protocol has the highest information theory efficiency. Compared with the recent quantum dialogue protocol that two adjacent logic qubits need to be prepared to be in the same quantum state, the protocol is easier to execute experimentally because the protocol does not have the special request.

Provided is a magnetic resonance imaging apparatus that can suppress image quality deterioration caused by eddy component with a short time constant included in an eddy field. A magnetic resonance imaging apparatus according to an embodiment includes a controller and an image reconstruction unit. The controller executes a pulse sequence having spare time during the time after transient of a gradient magnetic field for dephasing, applied in a readout direction after a radio frequency (RF) pulse for excitation is applied, until the first RF pulse for refocusing is applied in the case where imaging based on a fast spin echo method is performed. The image reconstruction unit reconstructs an image from magnetic resonance data collected by executing the pulse sequence.