94results about How to "Compensate for interference" patented technology

A memory system uses multiple pulse amplitude modulation (multi-PAM) output drivers and receivers to send and receive multi-PAM signals. A multi-PAM signal has more than two voltage levels, with each data interval now transmitting a “symbol” at one of the valid voltage levels. In one embodiment, a symbol represents two or more bits. The multi-PAM output driver drives an output symbol onto a signal line. The output symbol represents at least two bits that include a most significant bit (MSB) and a least significant bit (LSB). The multi-PAM receiver receives the output symbol from the signal line and determines the MSB and the LSB.

An apparatus and method for receiving high-speed signals having a wide common-mode range with low input-to-output latency. In one embodiment, the receiver includes an integrator to accumulate charge in accordance with an input signal during an integration time interval to produce an output voltage. A sense amplifier samples and converts the output voltage of the integrator to a logic signal; and a latch stores the logic signal. In an alternate embodiment, a preamplifier conditions the input signal prior to being integrated. In another embodiment using multiple receivers, circuitry is added to the receiver to compensate for timing errors associated with the distribution of the timing signals. In yet another embodiment, the integrator is coupled to an equalization circuit that compensates for intersymbol interference. In another embodiment, another circuit compensates for accumulated voltage offset errors in the integrator.

The invention relates to the research field of a microgravity simulating platform of a space robot, in particular to a microgravity air floatation target satellite simulator system with five degrees of freedom. The system consists of three parts, namely a movement simulator, a satellite simulator and a ground control panel. The movement simulator simulates the states of zero gravity, low friction and micro interference of a base satellite; the satellite simulator has a basic single-shaft attitude adjustment and track control function under a condition that a satellite provided by the movement simulator is in a track movement simulating environment, comprises a sensor, a controller and an actuating mechanism (a counteractive flywheel and a cold gas injecting system), and is provided with auxiliary systems such as a power system, a wireless communication assembly, a structural component and the like; and the ground control panel provides a basic function of the wireless data communication between a target satellite and the ground, and realizes the control on the target satellite and the receiving, storage and display of the data.

The invention discloses an MEMS gyroscope robust self-adaptation control method based on neural network upper bound learning. The method includes the following steps that an ideal kinetic model and an MEMS gyroscope kinetic model are established, a sliding mode function is designed, a control law is obtained based on the sliding mode function, and an RBF neural network upper bound estimated value is used as a gain of a robust item on the basis of the control law together with a feedback item and the robust item; a parameter self-adaptation law and a network weight self-adaptation law are designed based on a Lyapunov method. According to the MEMS gyroscope robust self-adaptation control method based on neural network upper bound learning, the feedback item is added in the control law, the two-shaft vibration trajectory tracking speed and the parameter estimation speed of an MEMS gyroscope are greatly increased, and the vibration amplitude is decreased; the robust item based on RBF neural network upper bound learning is added in the control law, the buffeting problem caused by large external disturbance and fluctuation and the problem that the dynamic characteristics are changed worse are solved, the uncertainty of a structural formula and the uncertainty of a non-structured formula are eliminated, and therefore the robustness of the system is further improved.

The invention compensates for any interference from a mobile communication unit to a positioning receiver unit in a multiple standard communication device with mobile communication and localization functionality. A first sub-unit receives input signals at a predetermined input level. A second sub-unit transmits output signals at an output level that is large compared to the input level of the first sub-unit. A branch-off unit branches off a part of the output signal before the antenna of the second sub-unit. An interference suppression unit receives the branch-off part of the output signal and derives an interference compensation signal therefrom through attenuation and subsequent phase shifting. The interference compensation signal is supplied to a superposition unit that also receives the input signal of the first sub-unit.

A multi-wavelength VECSEL includes an active region comprising a plurality of semiconductor quantum wells having an intrinsically broadened gain with a wavelength selective filter disposed within the cavity to provide a laser output that oscillates at two or more separated wavelengths simultaneously. A non-linear crystal may be provided in the cavity to emit radiation at a frequency in the THz range that is the difference of the frequencies associated with two of the separated wavelengths.

The invention discloses a micro gyroscope adaptive control method based on model reference, and the method is applied to a controller comprising a gyroscope. The method comprises the following steps: establishing an ideal dynamics model; designing a reference model as two different frequency sine waves, wherein a state space form is X[m]=A[m]X[m]; establishing a micro gyroscope system dynamics model; controlling a micro gyroscope based on a Lyapunov method, wherein a design control law is u=K<T>X+K[f]e, K<T> is an on-line adaptive update controller parameter, and K[f] is a steady matrix, and selecting K[f] and allowing (A[m]+BK[f]) as a stabilization matrix. According to the invention, a model reference adaptive control method is applied to micro gyroscope control in order to compensate manufacture errors and environment interference, and estimate an angle rate correctly. By employing a designed self-adaptive algorithm based on the Lyapunov method, global progressive stability of a whole control system is ensured, and reliability and robustness to parameter change of the system are raised.

The invention discloses a parameter optimization control method of semiconductor advance process control (APC). In semiconductor technological process, a traditional method uses a linear prediction model for the optimization control method of batch process. The parameter optimization control method of the semiconductor advance process control uses an optimized back propagation (BP) neural network prediction model based on genetic algorithm, optimizes the initial weight values and threshold values of the neural network through the genetic algorithm, uses selecting operation, probability crossover and mutation operation and the like according to the fitness function F corresponding to each chromosome, and outputs the optimum solution finally to determine the optimum initial weight value and the threshold value of the BP neural network. The performance of the BP neural network is improved with an additional momentum method and variable learning rate learning algorithm being used, so that the BP neural network after being trained can predict the non-linear model well. The genetic algorithm in the method has good global searching ability, a global optimal solution or a second-best solution with good performance is easy to obtain, and the genetic algorithm well promotes the improvement of modeling ability of the neural network.

The invention discloses a micro gyroscope robust self-adaptive control method, and the method is applied to a controller comprising a micro gyroscope. The method includes the following steps of establishing an ideal dynamics model, establishing a dimensionless dynamics model of the micro gyroscope, designing a sliding mode function and making the derivative of the sliding mode function to time be zero to acquire a control law, adding a feedback item and a robust item to the control law, wherein the control law with feedback item and the robust item is used as a robust self-adaptive control law, controlling the micro gyroscope based on the Lyapunov function method, and designing an self-adaptive law. According to the micro gyroscope robust self-adaptive control method, the feedback item is added to the control law, so that micro gyroscope two axle vibration trajectory tracking and parameter estimation speed is greatly improved, and vibration amplitude is reduced; the robust item is added to the control law, so that external interference and parameter uncertainty are removed, and robustness and dynamic characteristics of a system are improved; the self-adaptive law is designed based on the Lyapunov function method, so that globally asymptotic stability of the whole system is guaranteed, and reliability of the system and robustness to parameter change are improved.

A watermark signal provider provides a watermark signal suitable for being hidden in an audio signal when the watermark signal is added to the audio signal, such that the watermark signal represents watermark data. The watermark signal provider includes a psychoacoustical processor for determining a masking threshold of the audio signal; and a modulator for generating the watermark signal from a superposition of sample-shaping functions spaced apart from each other at a sample time interval of a time-discrete representation of the watermark data, each sample-shaping function being amplitude-weighted with a respective sample of the time-discrete representation, multiplied by a respective amplitude weight depending on the masking threshold, the modulator being configured such that the sample time interval is shorter than a time extension of the sample-shaping functions; and the respective amplitude weight also depends on samples of the time-discrete representation neighboring the respective sample in time.

The invention belongs to the technical field of visible light communication, and particularly relates to a phase shift coding method based on a direct-modulation direct-detection pulse amplitude modulation system and an implementing device. At a system transmitting end, a phase shift coding method opposite in symbol is adopted for odd-even code elements of a continuous symbol sequence; at a system receiving end, a differential decoding method of delayed subtraction is performed on adjacent symbols receiving the code elements. In the implementing device, a transmitting end comprises a phase shift coder, a PAM (pulse amplitude modulation) mapping module, a serial-to-parallel/parallel-to-serial conversion module, an up-sampling module, an LED and a driving module of the LED; a receiving end comprises a differential decoder, a serial-to-parallel conversion module, a rear balance module, a PAM de-mapping module, a clock synchronizing module, a normalization module, a down-sampling module, a focusing lens, a light filter and a receiver. By using the implementing device and the coding and decoding method, crosstalk noise between inherent direct-current component and signal in a visible light communication system based on a pulse amplitude modulation format can be effectively eliminated, sensitivity of the receiver can be improved, signal transmission quality can be improved, and system performance can be improved effectively. The method is simple to implement and easy in integration.

The invention discloses a robust adaptive nonsingular terminal sliding-mode control method of automatic train operation. The method comprises that S1) the bearing condition of vertical movement of a train is analyzed, and a train vertical movement power equation including unknown parameters, uncertainty and external interference is established; S2) a nonsingular terminal sliding-mode surface is constructed; S3) an adaptive law of estimated values of the unknown parameters and a parameter equation of parameters of the sliding mode surface are designed; and S4) the nonsingular terminal sliding-mode surface, the adaptive law of estimated values of the unknown parameters and the parameter equation of parameters of the sliding mode surface are substituted into the train vertical movement power equation including the unknown parameters, uncertainty and external interference, a nonsingular terminal sliding-mode closed-loop control equation is obtained, and the nonsingular terminal sliding-mode closed-loop control equation is used to implement robust adaptive nonsingular terminal sliding-mode control of automatic train operation. Thus, position and speed tracking errors of an ATO system can reach the sliding surface within limited time and converged to 0 within limited time.

The invention discloses a cantilever beam robustness self-adaptation control method. An ideal cantilever beam dynamic model is designed and contains frequency signals rich enough to serve as a reference trajectory of a system, it is guaranteed that the actual cantilever beam trajectory can track the reference trajectory for the whole self-adaptation control system, an ideal dynamic property is realized, and compensation of manufacturing errors and environment disturbance is achieved. The parameters of a cantilever beam are taken as unknown system parameters, a parameter error vector theta is formed, a slip form function is designed, the derivative of the slip form function is made to be zero, an equivalent controller is obtained, a feedback term and a robustness term serve as an input signal on this basis, the self-adaptation rule of the parameter theta of the controller is designed based on the Lyapunov method, the stability of the system is guaranteed, tracking error is converged to zero, and all the parameters are converged to true values.

The invention relates to a multi-band Raman amplifier pumping source, wherein an optical pumping device provides pumping sources for the Raman amplifier in a single C-band or C-band and L-band. The first pump unit provides the necessary optical pump energy for a flat gain response in the C-band. The second pump unit operates with an upgraded module capable of extending the pumping range to L-band. The second pump unit provides two pump energies for the extended part of the gain spectrum. The pump energy for the C-band will also compensate for any disruption of the gain spectrum. In this way, a flat gain response is maintained in the C-band and L-band. .

The invention discloses a self-adaptive RBFNNs noise-measurement active-disturbance-rejection control method for a rotor wing flight manipulator. The method comprises the following steps that the rotor wing flight manipulator is subjected to stress analysis, and a Newton-Eulerian method is used for establishing a dynamics model of the rotor wing flight manipulator; a height controller and a levelcontroller based on RBFNNs\ADRC are designed; according to the dynamics model and the actual flight conditions of the rotor wing flight manipulator, the output of the level controller is converted into an expected attitude angle; an attitude controller based on RBFNNs\ADRC is designed; according to a flight mode of the rotor wing flight manipulator, control signals are converted into all rotor wing rotation speed values. According to the method, self-adaptive RBFNNs are utilized for estimating inner and outer disturbance of all channels of the flight manipulator and conducting real-time compensation, on this basis, the attitude controller based on RBFNNs\ADRC is designed, the disturbance of the movement of the manipulator to a flight platform can be effectively compensated for, and the rotor wing flight manipulator in the flight process can stably grip.

The invention discloses a micro gyroscope self-adaptive fuzzy sliding mode control method based on a dynamic surface. The micro gyroscope self-adaptive fuzzy sliding mode control method is characterized by comprising the steps of a first step, establishing a mathematical model of a micro gyroscope; a second step, approximating a summation of a dynamic characteristic of the micro gyroscope and an outer interference by means of a fuzzy control method; a third step, designing a self-adaptive fuzzy sliding mode controller based on the dynamic surface; and a fourth step, controlling the micro gyroscope based on the self-adaptive fuzzy sliding mode controller. A system can reach a stable state in a high speed. The dynamic characteristic of the micro gyroscope is an ideal mode. A manufacture error and an environment interference are compensated. The algorithm which is designed based on the dynamic surface method has advantages of reducing number of introduced parameters, simplifying calculation and reducing buffeting. The self-adaptive fuzzy sliding mode control can compensate the system designing parameter error and the outer interference and furthermore improves system validity.

The invention discloses a control method for piston motion track of a free piston engine, and belongs to the technical field of control. The invention aims to provide the control method for the piston motion track of the free piston engine, and the control method establishes a free piston internal combustion engine generator mechanism model system under an MATLAB environment according to the working mechanism of the free piston internal combustion engine generator, can effectively compensate interferences and keeps stable operation of the free piston internal combustion engine generator. The control method comprises the following steps of: establishing a free piston electric generator simulation model; controlling piston track of the free piston electric generator; enabling track of the piston to trace reference track, wherein the reference track is that a FPEG works under load needed for a driver; establishing a control-oriented model; designing a quadric-form secondary optimal controller; expanding design of a state observer; and performing uncertainty compensation. According to the control method disclosed by the invention, a control-oriented simplified model of the system is established, a piston motion control method based on linear quadratic type (LRQ) and extended state observer (ESO) is disclosed, and piston motion track of EPEG is controlled by regulating circulating oil spray amount.

The invention discloses a receiving end IQ imbalance estimation and compensation method and device for an SC-FDE system, and the stream analysis of modulated data is performed at a transmitting end. CP is added to a data block, and the data block is received by a receiving end through a wireless channel and noise interference. The received signal introduces IQ imbalance because of the hardware damage of a radio frequency end. The method provided by the invention comprises the steps: carrying out the FFT of time domain data to a frequency domain after the CP of data is removed at the receivingend; estimating the channel information in advance through pilot frequency data, and obtaining an IQ imbalance parameter estimated value; carrying out the mirroring of the received signal afterwards,carrying out the merging, and estimating the frequency domain data of an original signal through LS; and finally restoring the original data through IFFT and demodulation. According to the method provided by the invention, the pilot frequency data is used in the frequency domain for the separated estimation of the IQ imbalance parameter and channel in advance, and then a simple LS method is used for compensating for the IQ imbalance and channel interference. Moreover, the method can be suitable for SISO and MIMO systems.