386 results about "Linear operation" patented technology

The invention relates to a method and a circuit arrangement for the ageing compensation of an organic light-emitting diode (OLED) which is fed from a supply voltage and is switched by means of a driver transistor operated in saturation operation, by means of a driving of the light-emitting diode. The method comprises the following steps of: storing at least one desired current-voltage value pair of a desired current-voltage characteristic curve of the light-emitting diode; transferring the driver transistor from saturation operation to linear operation during a measurement cycle; measuring a current value for the current through the light-emitting diode by means of a current measuring circuit in the measurement cycle; determining at least one present current-voltage value pair of a present current-voltage characteristic curve of the light-emitting diode by means of the measured current value; comparing the at least one present current-voltage value pair of the light-emitting diode with the desired current-voltage value pair of the light-emitting diode; and generating driving parameters for driving the light-emitting diode in a manner dependent on the result of the comparison.

A transmission device and method are shown, wherein an amplification is implemented which can be changed between a switched operation mode and linear operation mode as desired, depending on which mode of operation best meets the needs of the radio system in use. This opens the possibility of using the same hardware for different systems.

A power amplifier (PA) provides dynamic stability and gain control for linear and non-linear operation. The PA operates with a baseband processor and a transmitter, in which the PA receives a signal from the transmitter for power amplification prior to transmission of the signal. The PA is configured to select between the linear mode of operation and the non-linear mode of operation, in which device scaling within the PA is achieved by changing a device sizing of at least one stage of the PA. Further to changing the device size, the PA changes biasing resistance and impedance of a matching network in response to the changing of the device size to control power output and stability for the PA.

A power amplifier configuration including power amplifier circuitry and power control circuitry and having improved Power Added Efficiency (PAE) is provided. The power amplifier circuitry includes one or more input amplifier stages in series with a final amplifier stage. The power control circuitry provides a variable supply voltage to the input amplifier stages based on an adjustable power control signal. The final amplifier stage is powered by a fixed supply voltage. In operation, as output power of the power amplifier is reduced from its highest power level, the variable supply voltage is reduced. Accordingly, RF power of an amplified signal provided to the final amplifier stage from the input amplifier stages decreases, and the final amplifier stage transitions from saturation to linear operation, thereby increasing the gain of the final amplifier stage. Thus, a desired output level can be maintained while operating at lower current levels.

Small portable communication devices that support multiple modulation techniques cannot gain the benefits of using an isolator at the output of a power amplifier to provide stability in the load impedance. However, for communication devices that include amplitude modulation schemes, maintaining linear operation of the power amplifier is still required. In the presence of unstable load impedance, this can be a difficult task. As a solution, the linearity of the power amplifier is detected by comparing the envelope of the output signal with the base band signal used to modulate the output signal. If the envelopes are similar, then the power amplifier may be operating in the linear region. When the linearity of the power amplifier degrades, there is an increase in the difference between the envelopes. By adjusting the power level of the input signal to the power amplifier when the envelope difference appears, linearity of the power amplifier is maintained.

The invention relates to a signal processing method which optimizes the bit error rate under pragmatic conditions. The signalling method is optimally matched to the radio channel, variable with time, in rapid sequence by means of linear operations. Uplink and downlink transmission sides are determined by an excess of antennae on the downlink transmission side. The estimations of the channel matrix in the one transmission direction, necessary for the matching of the transmitter, can, in the absence of common-channel distortions with the condition of channel reciprocity, be directly obtained from the estimations for the other transmission direction. By a suitable linear combination of the transmission signals and, optionally, also the received signals, an error-free bi-directional transmission of data streams can be achieved in Rayleigh and Rice channels with significantly lower transmission powers than in purely receiver-side linear signal processing.

A transmitter apparatus that exhibits a high efficiency and that can provide a wide variable output control width. An operation of saturation mode is performed in the vicinity of the maximum transmission power. A large-power amplifier (12) is caused, by increasing and then fixing the input level thereof, to operate in a saturation state, while the amplitude component of a modulation signal in a range corresponding to an output power control level is inputted to an R-input terminal (33) to amplitude modulate the power supply voltage (VDD) of a power supply terminal (25), thereby performing a polar coordinate modulation of a high efficiency. An operation of linear mode is performed for a smaller transmission power. The large-power amplifier (12) is caused, by reducing the input level thereof, to perform a linear operation, while the power supply voltage (VDD) of the power supply terminal (25) is varied in accordance with the output power control level, thereby performing a transmission power control.

The present invention proposes a dynamically reconfigurable multistage parallel single instruction multiple data array processing system which has a pixel level parallel image processing element array and a row processor array parallel. The PE array mainly implements a linear operation which is adapted to be executed in parallel in the low and middle levels of image processing and the RP array implements an operation which is adapted to be executed in row-parallel in the low and middle levels of image processing or more complex nonlinear operations. In particularly, such a system may dynamically reconfigure a SOM neural network in a low cost of performance and area, and the neural network supports high level of image processing such as a high speed online neural network training and image feature recognition, and completely overcomes a defect in which a high level of image processing can't be done by pixel-level parallel processing array in the existing programmable vision chip and parallel vision processor, and facilitate an intelligent and portable real time on-chip vision image system with a complete function at low device cost and low power consumption.

A transmitter includes a power amplifier which is capable of both linear and non-linear operation, controlled by first and second control loops. A power controller includes a capacitive component, and controls the gain of the power amplifier. A ramp generation circuit provides a control signal to the power controller. It includes a ROM which stores ramp data values based on samples of a predetermined ramp shape. The ramp shape is based on a generally regular profile C, for example a cos² or cos⁴ function. The ramp shape also includes a boost portion BP, which enhances the ramp data values before the beginning of the generally regular profile C. The boost portion BP causes the capacitor in the feedback loop of the relevant control loop to become fully charged more rapidly, which produces a corresponding increase in the output power of the power amplifier shortly after the generally regular profile C is applied. This allows the transmitter to follow the generally regular profile C of the ramp signal at an earlier time when compared with the prior art. The size of the boost portion BP can be adjusted dependent on a detected temperature.

A voltage divider network in combination with a voltage multiplier circuit voltage biases the electrodes of a photomultiplier tubes or related device. The circuit exploits the several voltage levels produced at successive stages of a voltage multiplier circuit in order to optimize the voltage divider network with respect to power consumption, current draw from the power supply, operating stability, and linear operation of the photomultiplier tube.

The invention discloses a distributed storage method and a distributed storage device based on network coding, and belongs to the technical field of computer storage. The method and the device solve the problem that disk IO (Input/Output) of storage nodes is too large in the existing distributed storage method based on the network coding. The distributed storage method is suitable for a distributed storage system, and comprises the steps of data coding, data decoding and data repair. The distributed storage device comprises a data coding module, a data decoding module and a data repair module. According to the method and the device, when a data node is damaged, data not more than the size of a primary file D is downloaded from d data nodes, and the damaged data is repaired, so that the repair band width is reduced effectively; and randomly selected gamma coded data blocks are downloaded directly from the d data nodes, and the data blocks are not subjected to linear operation in the data nodes, so that the disk IO of the storage nodes can be reduced on the premise that the high usability of the data is ensured, and the disk IO efficiency of the data nodes is improved effectively.

L overlapping forward subarrays with {overscore (q)} (≧q) antenna elements are formed with, where q is the number of desired signals, a cyclic correlation matrix is formed from the cyclic correlations between the received signals of L forward subarrays and a received signal of the first predetermined antenna element, the cyclic correlated matrix is divided into two upper and lower submatrices, an orthogonal projection operator in the noise subspace is calculated by performing a linear operation on these two upper and lower cyclic correlation matrices, then by calculating a spatial spectrum or a polynomial by using the estimated orthogonal projection operator, the directions are estimated from of the position of q highest peaks of the spatial spectrum or the phases of q roots of the polynomial closest to the unit circle in z-plane.

The invention discloses a natural sense color fusion method based on color contrast enhancement, which includes that at the same time, a frame of optical registering grayscale image is respectively extracted from an infrared light video and a visible light video; linear operation is performed on the two frames of grayscale images, and the two frames of grayscale images are mapped to a luminosity ab (Lab) color space to obtain a pseudo-color fusion image of a two-waveband image, and a fused coefficient with optimal effect is selected by an observer; a group of pre-stored white light reference images is used for performing color transfer on the pseudo-color fusion image, and a reference image is selected by the observer; the selected reference image is used for performing natural sense color correction with the color contrast enhancement on the pseudo-color fusion image; and the reference image and the coefficient which are obtained in the previous step are used for performing rapid natural sense color fusion with the color contrast enhancement on the infrared light video and the visible light video. The fusion method can solve the problem that target and background color contrast of the natural sense color fusion of a two-waveband video is low in the prior art.

Hardware accelerator for compressed Long Short Term Memory (LSTM) is disclosed. The accelerator comprise a sparse matrix-vector multiplication module for performing multiplication operation between all sparse matrices in the LSTM and vectors to sequentially obtain a plurality of sparse matrix-vector multiplication results. A addition tree module are also included for accumulating a plurality of said sparse matrix multiplication results to obtain an accumulated result. And a non-linear operation module passes the accumulated results through an activation function to generate non-linear operation result. That is, the present accelerator adopts pipeline design to overlap the time of data transfer and computation for compressed LSTM.

The invention discloses a joint estimation method for an azimuth angle and an elevation angle of a signal on the basis of an L-type sensor array. The joint estimation method is used for estimating a direction of arrival of an incidence signal emitted onto the L-type sensor array, wherein the L-type sensor array is placed on an x-z plane and is provided with two mutually vertical uniform linear arrays, and M omnidirectional sensors are equidistantly arranged in different spatial positions along a straight line on each of the uniform linear arrays. The joint estimation method is characterized by comprising the following steps: (1) estimating a covariance matrix of signals received by two rows of uniform linear arrays on x axis and z axis, and then obtaining an M*2M expanding cross covariance matrix by calculating according to the covariance matrix of the signals received by the two rows of uniform linear arrays; (2) cutting the uniform linear array on the z axis or x axis into two rows of non-coincident forward/backward sub-arrays, and then estimating the elevation angle by utilizing the expanding cross covariance matrix of data received by the two rows of uniform linear arrays according to a linear operation one-dimensional subspace method; and (3) estimating a corresponding azimuth angle by linearly operating by utilizing feasible regions of the azimuth angle and the elevation angle, the two rows of sub-arrays on the z axis or x axis and the cross covariance between one of the sub-array and the uniform linear array on the x axis or z axis.

A system and method for controlling tendon-driven manipulators that provide a closed-loop control of joint torques or joint impedances without inducing dynamic coupling between joints. The method includes calculating tendon reference positions or motor commands by projecting a torque error into tendon position space using a single linear operation. The method calculates this torque error using sensed tendon tensions and a reference torque and internal tension. The method can be used to control joint impedance by calculating the reference torque based on a joint position error. The method limits minimum and maximum tendon tensions by projecting the torque error into the tendon tension space and then projecting ii back into joint space.

The invention provides an analytic hierarchy process based coal bed methane comprehensive evaluation method and belongs to the field of seismic exploration and development of oil gas and coal bed methane. The method includes: (1) acquiring main controlling factors of coal bed methane enrichment by means of areal geology analysis; (2) constructing a judgment matrix according to the main controlling factors; (3) calculating weight values of elements, standing for the main controlling factors of coal bed methane enrichment, in the judgment matrix; (4) setting a coal bed methane enrichment area as a research object layer, setting the main controlling factors as a reference layer, and completing comprehensive evaluation of the coal bed methane enrichment area according to an analytic hierarchy process. The analytic hierarchy process based coal bed methane comprehensive evaluation method has the advantages that by means of a geophysical method and the AHP (analytic hierarchy process), weighting coefficients of the main controlling factors of coal bed methane are obtained by calculation; by means of linear operation and relevant physical geographical predication technological achievements, a coal bed methane comprehensive evaluation map of the coal bed distribution area is obtained, and an evaluation result and an actual drilling result are highly uniform.

The invention provides a voltage regulation switch power supply relating to electric technique field. The power supply output voltage dc amount is detected by a voltage ripple detecting circuit and fed back to a control circuit to control the turn-on and turn-off of the power switch tube thus to realize regulated output. The voltage ripple detecting circuit of the voltage regulation switch power supply provided by this invention comprises a high pass filtering module, a second order differentiation operation module, a linear operation module, and a clock gating/signal memory module which are connected in series sequentially. The voltage ripple of the voltage regulation switch power supply output voltage is firstly extrated and then performed by second order differentiation, linear operation and memory extension to 'resume' the dc output voltage of the voltage regulation switch power supply which is finally fed back to PWM, PFM or PSM control ciucuit so as to realize regulated output via adjusting the turn-on and turn-off of the power switch tube by the control circuit. The present invention has higher power efficiency and lower circuit cost as well as smaller power supply volume compared with prior voltage regulation switch power supply.