57results about How to "Reduce Signal Error" patented technology

A packet data transmitting method and mobile communication system using the same enables transmission of common ACK/NACK information from each sector of a base station to a user entity in softer handover. The method includes receiving via at least one of the plurality of sectors a data packet from the mobile terminal, the data packet being correspondingly received for each of the at least one of the plurality of sectors; combining the correspondingly received data packets, to obtain a signal having a highest signal-to-noise ratio; decoding the value obtained by the combining; determining a transmission status of the data packet according to the decoding; and transmitting to the mobile terminal a common ACK/NACK signal including one of a common ACK signal and a common NACK signal according to the determining, the common ACK/NACK signal being transmitted via each of the at least one sector.

The invention relates to a thermal power generating unit reheated steam temperature controlling method. According to the operating characteristics of the boiler reheater and the theoretic study on a steam-temperature control system, a state feedback control method based on incremental state observer is adopted, and the concept of an algebraically equivalence observer is used to direct the parameter setting of an incremental state observer; in addition, a special control circuit is arranged in the steam-temperature control circuit to resolve the problems that the process of steam-temperature adjustment is relatively long when the reheated steam temperature set value is changed, non-linearity exists during steam-temperature control, the process of steam-temperature variation is very slow, etc., and variation parameter PID regulator is combined to jointly form a comprehensive reheated temperature automatic adjusting system. The invention is capable to ensure reheated steam temperature control to escape spray water upon large-range load variation, and effectively overcomes the disadvantage of the poor effect of the traditional PID regulation on the control of big lagged object; the reheated temperature control effect is improved remarkably; and a sample is provided for controlling the controlled object with big inertia and serious lagging in relation to reheated steam temperature.

The invention discloses a household video monitoring system. The system comprises a frequency acquisition circuit 1, a frequency acquisition circuit 2, a rectification calibration circuit and a filtering output circuit. The frequency acquisition circuit 1 and the frequency acquisition circuit 2 respectively acquire analog signals at the input end and the output end of a signal transmission channelin a control terminal of the household video monitoring system. The rectification calibration circuit uses a variable resistor RW1, a capacitor C4, and a capacitor C3 to form a rectifying circuit torectify the signal, and uses a diode D6-diode D9 and an amplifier AR1 to form a composite circuit for signal limiting, amplification, and limiting processing. The frequency acquisition circuit 2 usesthe op amp AR2-AR4 and the capacitor C14 to form a loss compensation circuit to compensate the output signal of the rectification and calibration circuit. Finally, the filter output circuit uses the inductor L2, the capacitor C10, and the capacitor C11 to form a [pi]-type filter circuit. The filtered output can convert the signal frequency into a compensation signal of the signal at the output endof the signal transmission channel in the control terminal of the home video monitoring system.

An optical disc using super-resolution effects that achieves higher-density recording exceeding the optical resolution suffers from the signal-quality degradation caused by the normal resolution component included in the reproduction signal. To address this problem, a data reproduction method is provided. In the method, characteristic error patterns are identified and parity check codes in conformity with run-length limited coding are used to carry out efficient and reliable error correction. Error patterns caused by the normal resolution crosstalk are localized in the leading edges of a mark following a long space and in the trailing edges of a long mark. Whether an error exists in the data is determined by use of the parity check codes. When an error occurs, a pattern in which an error is most likely to occur is selected from the above-mentioned patterns by taking account of the edge shift direction, and then the error therein is corrected.

The invention provides an indoor 3D dimension measurement method, which comprises the following steps of: setting up a coordinate system in an indoor 3D space and converting the distances and angles of sampling points into coordinates and describing the coordinates; adopting curve fitting based on the least square method to carry out fitting of the sampling points; according to the fitting results, judging the wall surface quality in the measurement direction in real time, and building up a geometric frame in the indoor space according to the combination of various scanning layers; and completing the measurement according to the corresponding 3D dimensions which need to be calculated. The invention can quickly and precisely complete the indoor 3D dimension measurement (including the irregular geometric measurements) and has high measurement precision and efficiency. In addition, because of not setting strict requirements for machine platforms, hardware, motion control and programming,the measurement method is quite easy to implement and quite applicable to the characteristics of extension, development and utilization of intelligent instruments and related applications.

The optical transmission equipment includes: a demultiplexer for demultiplexing a transmitted wavelength-multiplexed optical signal to first and second optical signals; a first variable dispersion compensation unit; a second variable dispersion compensation unit; a first error detector; a second error detector; and a dispersion compensation control unit for controlling dispersion compensation amounts of the first and second variable dispersion compensation units based on the detection result of the first or second error detector. Upon detection of a signal error in the first optical signal, the first variable dispersion compensation unit is controlled to change from a first compensation amount to a third compensation amount, and the second variable dispersion compensation unit is controlled to change from a second compensation amount to a fourth compensation amount.

The invention discloses a clock jitter estimation and correction method for data acquisition in a rotating environment, which performs jitter distribution estimation by combining a sampling clock signal and an external clock input signal in a wireless transmission mode, and directly estimates a clock jitter amount by utilizing a signal-to-noise ratio of clock signal acquisition data. Interpolationcorrection is performed according to the jitter amount estimation result, so that the problem of data acquisition errors caused by serious jitter of an external clock input signal of the data acquisition system in a rotating environment is solved, the phase error of the external clock input signal is reduced, and the precision and accuracy of data acquisition are improved. Compared with the priorart, the method has the advantages of multi-channel acquisition, comprehensive jitter amount estimation and the like, can obviously reduce external clock jitter, and is also suitable for improving external clock input stable transmission of a data acquisition system.

The invention discloses a signal calibration circuit for an industrial building fire fighting system. The signal calibration circuit for the industrial building fire fighting system comprises a frequency acquisition circuit, a mean push-pull circuit and a filtering emission circuit; the frequency acquisition circuit acquires a signal frequency of an input end in an analog signal transmission channel in a signal transmission module of the industrial building fire fighting system; a first path of the mean push-pull circuit applies an operational amplifier AR1 to follow up a signal, and a secondpath of the mean push-pull circuit applies an operational amplifier AR4 and a triode Q3 as well as a capacitor C2 to form a noise reduction circuit to reduce a signal-to-noise ratio; then an operational amplifier AR2 is applied to carry out addition processing on two paths of signals; an output signal of the operational amplifier AR2 is input into a mean circuit consisting of an operational amplifier AR3 and a diode D2 as well as a diode D3; the filtering emission circuit applies an inductor L2 and a capacitor C4 as well as a capacitor C5 to form a filtering circuit to carry out filtering on the signal; the filtered signal is sent into a control terminal of the industrial building fire fighting system through a signal emitter E1; and after being automatically calibrated, the signal is converted into an error correction signal of the control terminal of the industrial building fire fighting system.

The invention discloses a controllable small-signal voltage source plate, which comprises a power circuit, an upper computer, a serial communication circuit, a single-chip microcomputer, a digital-to-analogue conversion circuit, a reference voltage source circuit, a signal processing circuit and a second-order filter circuit, wherein the power circuit is connected to the single-chip microcomputer; the single-chip microcomputer is connected to the upper computer through the serial communication circuit; the input end of the digital-to-analogue conversion circuit is connected to the single-chip microcomputer and the output end of the digital-to-analogue conversion circuit is connected to the signal processing circuit; the reference voltage source circuit is connected to the digital-to-analogue conversion circuit; and the signal processing circuit is connected to the second-order filter circuit. An output voltage signal can be precisely controlled through the upper computer and the single-chip microcomputer, the manual adjustment of the voltage signal is not needed, and the adjustment is convenient and flexible; through a digital-to-analogue converter, the signal error is reduced and the signal precision is improved; through the second-order filter circuit, the signal jitter is reduced, so that the signal is more stable when the signal is output.

The invention discloses a torque monitoring system of a four-wheel-drive system of an electric automobile. The torque monitoring system of the four-wheel-drive system of the electric automobile comprises a torque signal collection circuit, a push-pull frequency modulation circuit and a limiting filtering circuit; the torque signal collection circuit uses a torque sensor J1 with model of TQ-663 tocollect a torque signal during the working of the four-wheel-drive system of the electric automobile; the push-pull frequency modulation circuit uses a triode Q1 and a triode Q2 to form a push-pull circuit to receive a signal output by the torque signal collection circuit and uses resistors R13-R15 and capacitors C5-C7 to form a double T frequency selection circuit to screen a signal with single frequency; and finally, the limiting filtering circuit uses a diode D5 and a diode D6 to form a switch circuit to limit the signal and uses an inductor L1 and a capacitor C9 and a capacitor C10 to forma Pi-type filtering circuit to filter the signal and output the filtered signal. A torque signal in a signal transmission module of the torque monitoring system of the four-wheel-drive system of theelectric automobile can be automatically frequency-modulated and calibrated, and the signal is compensated to prevent frequency hopping and attenuation phenomenon of the signal.

The invention discloses a nozzle driving circuit for inkjet printers, comprising a drive signal generating circuit, a D/A (Digital/Analogue) switching circuit, a power amplifying circuit and a self-check feedback circuit, wherein the drive signal generating circuit is used for outputting digital signals of a drive voltage; the D/A switching circuit is used for converting the digital signals of the drive voltage output by the drive signal generating circuit, into analogue signals; the power amplifying circuit is used for amplifying the analogue signals of the drive voltage subjected to the conversion of the D/A switching circuit; the self-check feedback circuit is used for checking whether a nozzle driving voltage is output in a preset linear mode or not after the amplification of the power amplifying circuit; and the amplified drive voltage is compared with a drive voltage obtained through theoretical calculation and the comparative result is fed back to the drive signal generating circuit to ensure that the output digital signals of the drive voltage can be adjusted according to the comparative result through the drive signal generating circuit. According to the invention, the signal error is reduced through carrying out self-check and feedback on the nozzle driving voltage, therefore, the printing quality of the inkjet printers is improved.

A high bandwidth, low signal error, compact waveguide includes a conductive body including a waveguide input portion and a plurality of waveguide output portions disposed coplanar with the input waveguide portion. The waveguide further includes a common junction joining the input waveguide portion and the plurality of output waveguide portions. A septum is disposed proximate the common junction collinear with a centerline of the input waveguide portion. The waveguide further includes a plurality of iris elements disposed proximate the common junction transverse to the centerline of the input waveguide portion. The septum and the plurality of iris elements changes an impedance of the common junction to match the impedance across the entire waveguide bandwidth.

The invention relates to a quantitative determination method for medium-chain triglycerides in a tobacco breakable bead solvent, and belongs to the field of tobacco additive component physical and chemical analysis. The quantitative determination method for medium-chain triglycerides in the tobacco breakable bead solvent comprises the following steps of carrying out mixing and extracting on crushed tobacco breakable beads, an extracting agent and an internal standard substance, and taking the supernate to carry out GC-FID measurement, and performing quantifying by an internal standard method,wherein the extracting agent is ethanol, acetone or dichloromethane. According to the method disclosed by the invention, the quantitative detection of the four components of the medium-chain triglycerides in the cigarette breakable bead solvent is realized for the first time, and the method has the advantages of being low in detection cost, rapid in detection, high in sensitivity and high in accuracy, and is suitable for quantitative detection of medium-chain triglycerides in the cigarette breakable beads and commercial medium-chain triglycerides.