114results about How to "Improve SNR" patented technology

An illumination system for increasing a light signal from an object passing through a reflection cavity. The reflection cavity is defined by spaced-apart, opposed first and second surfaces disposed on opposite sides of a central volume. Preferably the first reflecting surface forms an acute angle with the second reflecting surface. A beam of light is directed into the reflection cavity so that light is reflected back and forth between the first and second surfaces a plurality of times, illuminating a different portion of the central volume with each pass until, having ranged over the central volume, the light exits the reflection cavity. The “recycling” of the light beam in this manner substantially improves the signal to noise ratio of a detection system used in conjunction with the reflection cavity by increasing an average illumination intensity in the central volume.

The invention discloses a method for reconstructing a parallel-acquired image, comprising: generating reconstruction data by combining uniformly under-sampled data and low-frequency fully-sampled data in magnetic resonance imaging (MRI) K-space according to a hybrid sampling mode; calculating the sensitivity distribution of a coil according to the low-frequency fully-sampled data; and reconstructing an image according to the reconstruction data, the sensitivity distribution of the coil and the hybrid sampling mode. The invention also discloses an apparatus for reconstructing the parallel-acquired image. The method and the apparatus are adopted to generate reconstruction data by combining uniformly under-sampled data and low-frequency fully-sampled data in K-space according to the hybrid sampling mode and take the hybrid sampling mode into account during the image reconstruction, and the signal to noise ratio of the reconstructed image is effectively improved by using the reconstruction data combined with the low-frequency fully-sampled data in reconstructing the image since the low-frequency fully-sampled data contains more useful information.

A method for adjusting the signal to noise ratio of a receiver comprises measuring the peak power for an RF signal and determining, based on the measured peak power, whether the RF signal power is within a desired operating range. The method further includes adjusting an RF attenuation for the receiver, when it is determined that the RF signal power is not within the desired operating rang. The method further comprises measuring a peak power foe an IF signal, determining based on the measured peak power, whether the IF signal power is within a desired operating range, and adjusting an IF attenuation for the receiver, when it is determined that the IF signal peak power is not within the desired operating range.

This invention solves a problem of registration and improves signal-to-noise ratio (SNR) when using division-by-focal-plane array to produce multiple polarization images. This is achieved by processing a sequence of angular-position-dithered frames to generate a high-definition, Nyquist-sampled, integrated image for each of the polarizations. The integration method transforms individually under-sampled, high-resolution image frames into resultant high-resolution frames that meet the Nyquist sampling criterion. During the resampling transformation, each polarization or waveband is resampled to produce precise registration to the other polarizations, since registration offsets are fixed and defined by the arrangement of the polarized pixels in the focal-plane-array. In the most straight-forward implementation, these offsets would be integer pixel shifts in X and Y.

ESR microscope systems and methods for examining specimens using both continuous wave and pulsed modes in the 9 to 60 GHz range. The ESR microscope uses an image probe comprising gradient coils in addition to conventional modulation coils (in continuous wave mode) or magnetic field bias coils (in pulse mode), and a resonator constructed from high permittivity material. The systems and methods also involves the use of sample containers that permit the precise placement of samples in relation to the image probe. The microscope uses a microstrip or thin coaxial or dielectric antenna to obtain a high coupling coefficient to the specimen being imaged. The microscope systems provide resolution at the single micron level, and permit the observation of images comprising tens to hundreds of pixels for each of two or three dimensions in a few minutes. Novel stable radicals used as the imaging media are also described.

The invention discloses a single-channel synthetic aperture radar moving target detection and positioning method based on two-view real image processing. The steps include: (1) calculating the azimuth spectrum; (2) separating sub-view images; (3) suppressing ground clutter ; (4) Using the constant false alarm detection method to detect moving targets; (5) Locating moving targets. The invention overcomes the disadvantages of multi-channel hardware system complexity, high cost and narrow application range by adopting the single-channel SAR-GMTI method, and has the advantages of simple hardware system, low cost and wide application range. Through adaptive amplitude filtering of the two-view real image and then suppressing the interference of static clutter, it overcomes the fact that there is still a large amount of static clutter left after the sub-view image cancellation of the existing single-channel system, and can only detect moving targets outside the main lobe of clutter The shortcomings of the signal have the advantages of high signal-to-noise ratio, the ability to detect moving target signals in the main lobe of clutter, low false alarm probability, and high accuracy of motion parameter estimation and positioning.

The invention relates to the field of radar signal processing and especially relates to a radar anti-interference method by utilizing polarization cancellation. In the method, through determining a cancellation main channel and an accessory channel, and then, by utilizing the main channel and the accessory channel as well as channel weight coefficients thereof, no-interference signals are obtained after cancellation. The method is especially suitable for escort self-defense noise interference and general clutter interference; signal-to-clutter-noise ratio of the system can be greatly improved, detection of follow-up radar signal processing is convenient, and detection capability of the radar can be effectively improved under the complex electromagnetic environment.

Provided in the invention is an ionospheric clutter suppression method of a high-frequency ground wave radar. The invention relates to an ionospheric clutter suppression method of a high-frequency ground wave radar so that problems that the existing methods are mainly used for suppressing the narrowband radio-frequency interference and transient impact interference in the high frequency radar butnot suppressing the ionospheric interference, the existing methods are not suitable for wide-beam radars, and first-order Bragg peak information shortage and wave echo energy weakening are caused canbe solved. Compared with the traditional clutter suppression algorithm, the ionospheric clutter suppression method provided by the invention is characterized in that cancellation processing is completed by using the cross-correlation between the ionospheric multi-aggregation regional clutters; and the ionospheric clutters are suppressed, the wave echo and the first-order Bragg peak information arekept, and the declining in normal ocean echo energy is reduced. With the ionospheric clutter suppression method, the strong ionospheric clutter in the radar echo spectrum is obviously suppressed; theclutter suppression amplitude is improved, and the echo signal noise ratio is significantly increased. The ionospheric clutter suppression method is mainly applied to the high-frequency ground wave radar detection field.

A method of driving a touch display panel includes sequentially providing gate signals to a plurality of gate lines, outputting data signals to a plurality of data lines, the data lines being disposed on the first surface and crossing the gate lines, and reading out a first sensing signal through a plurality of sensing lines in response to the gate signals. The gate lines are disposed on a first surface of a base substrate, the touch display panel including the base substrate. The data signals are synchronized with the gate signals. The sensing line is disposed on a second surface of the base substrate, the second surface being opposite to the first surface.

The invention provides methods and systems useful for quickly and accurately sampling a switched capacitive load. Systems are disclosed in which the methods are implemented using an operational amplifier operably coupled to a pre-charge capacitor for storing an input charge. A sampling capacitor is also coupled to the operational amplifier and to the pre-charge capacitor for receiving and holding the input charge. The system is so configured for a coarse sampling phase and a fine sampling phase the to ensure that the sampling capacitor settles quickly to provides an output.

A method of processing audio signals for an auditory prosthesis is provided. The method includes a noise reduction step (22) and a later compression step (24). A gain control step is provided prior to the compression step (24). The gain control step operates so as to minimize the occurrence of signal compression in the compression step (24). An auditory prosthesis arranged to provide the method is also provided.

The present invention relates to a method and apparatus providing tissue harmonic imaging using an ultrasound machine. Coded pulses and the phase inverted version of the said coded pulses with time bandwidth greater than 1 are transmitted into the tissue. Backscattered echoes are received and filtered before or after coherent summation. Decoding / compressing of the received echoes of the coded pulses is implemented naturally through the propagation of the specially designed ultrawide band (>80%) waveforms inside tissue and pulse inversion. Costly decoding / compression filter are not necessary.

The invention discloses an anti-interference method based on an intelligent antenna and a neural network algorithm. According to the method, a back frame structure of the antenna is used as a model; based on an artificial neural network, an intelligent antenna structure deformation estimator and a shape controller are designed; an improved error algorithm is adopted, so that the characteristics of high convergence rate and small calculation amount are realized; and a relatively high anti-interference characteristic is achieved. A typical applicable type is adopted by the conventional artificial neural network topology structure; the intelligent antenna is combined, and a bipolar intelligent antenna is used, so that the convenience in actual operation is achieved; the capacity of the 8-unit bipolar intelligent antenna can be met; the coverage aspect is within a normal cell coverage range; and obvious coverage loss does not exist. The transverse size of the bipolar intelligent antenna is reduced by over 50 percent compared with the conventional single-polar intelligent antenna and has obvious advantages of reducing the windward area, reducing the engineering mounting difficulty and reducing the electromagnetic radiation panic of common users.

The method includes following procedures: receiving synchronizing pilot sequence, and obtaining oversampling in frequency domain for synchronizing pilot sequence; on discrete frequency spectrum of oversampling in frequency domain in synchronizing pilot sequence, calculating square of amplitudes of discrete frequency spectrum lines, and summarizing them in order to obtain measure sequence; based on measure sequence to carry out estimation for carrier frequency shift. The invention increases precision of estimating carrier frequency shift, and range of estimation remarkably without increasing complexity.

The present invention provides a Sigma-Delta analog-to-digital converter, which comprises first and second adders, first and second integrators, a first quantizer, a first-order Sigma-Delta modulation circuit of a first DA converter, third and fourth adders, third and fourth integrators, a second quantizer, a second-order Sigma-Delta modulation circuit of a second DA converter, and a noise shaping circuit for shaping the noises of the first-order Sigma-Delta modulation circuit and the second-order Sigma-Delta modulation circuit. The noise shaping circuit performs the integration and scale conversion on digital signals output by the first quantizer, performs the scale conversion on digital signals output by the second quantizer, and then adds up and outputs the converted signals. The Sigma-Delta analog-to-digital converter eliminates quantizing noise of the first-order Sigma-Delta modulation circuit and can improve SNR (signal to noise ratio) and reduce total harmonic distortion by cascading two Sigma-Delta modulation circuits of second order or more than two order and then performing noise shaping on signals output by the second-order Sigma-Delta modulation circuits.

An MRI k-space data set is acquired using a series of shell k-space sampling trajectories of different radii. Off-resonance effects are reduced and fat-suppression can be improved by using a shorter TR for pulse sequences that sample at smaller radii. At larger radii sampling is repeated with the central axis of the shell sampling trajectory tilted such that the polar regions of shells acquired at the same radii are sampled by the other shell.

A COFDM transmission scheme is provided that offers improved resilience to noise or deleterious effects in the transmission path. The scheme transmits two copies of the data on different symbols or carriers, if one version of the data is lost, the receiver can attempt demodulation of the surviving version. Furthermore, by using a different PAM mapping to encode each copy of the data, signal to noise performance and data rates are equivalent to conventional Quadrature Amplitude Modulation schemes, but with an improvement in SNR when transmission conditions are poor.

Provided is a transformer bushing insulation state on-line monitoring system. A PT signal conditioning module is connected to PT mutual inductors and a CT signal conditioning module is connected to CT mutual inductors. Three signal output channels of the PT signal conditioning module and three signal output channels of the CT signal conditioning module are connected to six signal input channels of an AD synchronous converter respectively. The signal output channels of the PT signal conditioning module are connected to a first signal input channel of a phase-locked loop module and a signal output channel of the phase-locked loop module is connected to a clock input channel. Data bus of the AD synchronous converter is connected to data bus of a master module and data bus of SRAM respectively, a channel control interface of the master module is connected to a channel control interface of the SRAM, and a signal output channel of the master module is connected to a second signal input channel of the phase-locked loop module. According to the invention, synchronous sampling of voltage and current is realized such that fundamental voltage measurement accuracy is not affected by frequency fluctuation of a grid system.

The invention relates to wireless communication networks, and to the way in which communication devices choose their transmission power when communicating with each other. More specifically, the invention relates to a method of controlling the transmission power of a first communication device in a wireless communications network based on the UMTS standard, the first communication device having established a HSDPA connection to a second communication device, whereby the absolute value of the difference between the HSDPA transmission power in a first transmission time interval (tti1) and the HSDPA transmission power in a subsequent second transmission time interval (tti2) is chosen to be smaller than a predetermined value (v). Furthermore, the invention relates to a node B which can carry out the method mentioned above, and power control means associated with said node B.

The purpose of providing an integrator circuit capable of alleviating disturbance of a current waveform of a current source DA converter is to improve the SNR of, for example, a ΔΣ modulator. An integrator circuit having an operational amplifier (102) with a feedback path (F1, F2) provided in parallel between an output terminal and an inverting input terminal of the operational amplifier (102). In the feedback path (F1), an integral capacitive element (105) and at least one resistive element (107) are arranged in series, and in the feedback path (F2), a second integral element having a capacitance smaller than the integral capacitive element (105) is provided. Capacitive element (106).

A passive radar device includes: a pulse-by-pulse range compression unit executing cross-correlation processing between received signals of a direct wave and scattered wave on each of pulses divided by a direct-wave reception unit and a scattered-wave reception unit, and calculating a pulse-by-pulse range profile; a block-by-block Doppler processing unit calculating a first Doppler frequency spectrum by executing pulse-direction Fourier transform in block units each grouping plural pulses; a Doppler frequency cell-associated range migration compensation unit compensating a range-direction movement amount with respect to the first Doppler frequency spectrum on a Doppler-frequency-cell-by-Doppler-frequency-cell basis and on a block-by-block basis; and a block-direction Doppler processing unit calculating a second Doppler frequency spectrum by executing block-direction Fourier transform on an output from the Doppler frequency cell-associated range migration compensation unit.

The invention discloses a circular scanning ISAR mode ship super-resolution imaging method and belongs to the radar technology field. The method comprises the following steps of dividing an echo signal in a circular scanning ISAR mode into M data frames and carrying out processing frame by frame; for a mth data frame, carrying out distance compression and selecting the sub-echo of the ship targetof a mth frame; pre-processing the sub-echo of the ship target of the mth frame, wherein preprocessing includes translation compensation and rotational compensation; using a Burg algorithm to carry out data extrapolation at an azimuth direction on the sub-echo of the ship target of the mth frame; randomly sampling extrapolated data in the azimuth direction; for the sampled data, carrying out compressed sensing calculation in the azimuth direction to obtain the sparse coefficient matrix of a current data frame; carrying out constant false alarm rate detection on the sparse coefficient matrix after compressed sensing, and acquiring the distance Doppler domain super-resolution image of the mth frame.

The invention relates to a radar micro-Doppler measurement system and method, and the system comprises a radar subsystem and a terminal subsystem. The radar subsystem is electrically connected with the terminal subsystem. The radar subsystem is used for transmitting radar signals, receiving echo signals of the radar signals and carrying out first-stage signal processing on the echo signals to generate target data information; and the terminal subsystem is used for controlling system parameters of the radar subsystem and is also used for carrying out second-stage signal processing on the target data information to complete detection of the micro-motion target so as to obtain micro-Doppler characteristic parameters. According to the radar micro-Doppler measurement system and method, a micro-motion target is sensed by the transmission of the radar signal, so as to achieve the detection of the micro-motion target. The system and method can adapt to a severe working environment, and the micro-Doppler characteristics of the micro-motion target can be measured all the time and all weather.

A method is provided for multiplexing control information with persistently scheduled data in a spectrally efficient operation. In particular, the invention operates to determine and send a power offset parameter in a message carrying a persistent data allocation from a base station to a corresponding mobile station. The power offsets are related to the control information being sent, and specify the amount by which the mobile should increase its transmit power level when multiplexing particular control information together with the persistent data. The increased transmit power then operates to maintain the required QoS on the data channel.

Current supply switch voltage clipper used in high-speed digital analog converter, belonging to electric installation field, is composed of eke-inverter consisting of connected PMOS tube and one NMOS tube, and another NMOS inserted in this eke-inverter and one standard inverter. The present invention can effectively reduce output signal burr and improve output signal SNR, raising high-speed digital analog converter total performance.

The present invention provides an X-ray dose compensation method for X-ray dose compensation of the detector signals from a multiple array detector with improved SNR, used for the detector signal detected by using the multiple array detector in which a plurality of X-ray detector channels placed in one dimensional array in the channel direction is stacked in a plurality of rows in the row direction to form X-ray detector channels of two dimensional matrix. A plurality of specific X-ray detector channels in the multiple array detector or X-ray planar detector or X-ray image intensifier are used as the X-ray dose reference channels for the X-ray dose compensation by means of signal sum or mean of detector signals from those X-ray dose reference channels.

A biometric feature identification device includes a substrate, an electrode layer, and a switch and trace layer. The electrode layer is arranged at one side of the substrate and has a plurality of electrodes. The switch and trace layer has a plurality of switches and a plurality of traces. The switches are provided to divide the plurality of electrodes sequentially or dynamically into at least one sensing electrode group and a plurality of deflection electrode groups corresponding thereto. Each sensing electrode group corresponds to at least two deflection electrode groups. Each sensing electrode group has at least one electrode for sensing. Each deflection electrode group has a plurality of electrodes for deflection.

A control means controls an imaging means for taking an image of a test object by a magnetic resonance, the test object being placed in an imaging space, and a transfer means that moves the test object, and on the basis of a difference (moving distance) between a position of the transfer means at the time of receiving a command of pausing the imaging and a position of the transfer means at the time of resuming the imaging, the control means controls the position of the transfer means or the position for imaging at the time of resuming, in such a manner that missing of data 503 caused by the difference can be compensated. With this configuration, it is possible to provide an MRI apparatus that is provided with an imaging pause function, and even when the pause function is activated, there is data consistency between the data before the pausing and the data after the resuming, thereby obtaining a high quality image.

The invention belongs to the technical field of wireless mobile communication, and discloses a full-duplex relay cooperative communication system performance optimization method based on NOMA. The method comprises: a base station sending a superposition code to the relay node and the near-end user in a broadcast form; the relay node decoding the received signal and recoding and forwarding the received signal, and the relay node decoding signals of the near-end user and the far-end user from the received signal; the relay node recoding the decoded signal and broadcasting the coded mixed signalto a far-end user and a near-end user; the base station and the relay node pre-coding the signal in a maximum ratio transmission mode and sending the pre-coded signal to a near-end user; the near-enduser and the far-end user decoding the received signal; the near-end user decoding the received signal by adopting an SIC method; the far-end user directly decoding own signal; and minimizing the interruption probability of the system is minimized, and the minimum reachable rate of the system. According to the method, the rate of near-end users is improved, and the total reachable rate of the system is improved.