130results about How to "Signal distortion is small" patented technology

The invention provides a refrigeration-type coaxial packaging light-emitting tube core, which comprises a transistor outline (TO) tube shell, a refrigerator, a heat sink, a laser carrier and a sealing tube cap, wherein the TO tube shell comprises a tube shell base. At least seven pins are arranged around the tube shell base; the pins comprise a radio frequency (RF) signal pin, and the laser carrier with a microstrip line is arranged on the RF signal pin; the radiating surface of the refrigerator and the surface of the tube shell base are fixed in the manner of sticking; the refrigeration surface of the refrigerator and the surface of the heat sink are fixed in the manner of sticking; the heat sink and the surface of the laser carrier with a matched resistor and the microstrip line are fixed in the manner of sticking; an electric absorption modulation laser chip, a backlight detector, a thermistor and a power filter capacitor are fixedly arranged on the surface of the laser carrier in the manner of sticking; one end of the microstrip line of the laser carrier is connected with the anode of an electric absorption modulator; and the other end of the microstrip line of the laser carrier is connected with a microstrip line on the RF signal pin through a conductor wire. When installation is performed, the emitted light outlet optical axis of the laser chip and the optical axis (OA) of the central axis of the TO tube shell are coaxial. Optical steering elements are not needed, the process is simple, and the signal distortion can be reduced.

An externally arranged ultrahigh frequency partial discharge detection sensor comprises a metal shielding outer shell, a microstrip antenna and a coaxial cable connector. The metal shielding outer shell is a box body with an opening at the bottom, and the lower bottom edge of the long side wall is arc-shaped. The microstrip antenna is arranged in the metal shielding outer shell and is a rectangular paster antenna. Long edges of a conductor paster are respectively provided with an inward concave arc notch, arc notches are symmetrically arranged using a geometric center of the conductor paster as a symcenter, the microstrip antenna is arranged in the metal shielding outer shell through a dielectric substrate, and an earth plate of the microstrip antenna is a metal shielding outer shell. An integrated circuit board is arranged in the metal shielding outer shell. A low noise amplifying circuit connected with the microstrip antenna, a detector circuit, an amplifying circuit which outputs signals through the coaxial cable connector, and a power supply circuit are arranged on the integrated circuit board. The externally arranged ultrahigh frequency partial discharge detection sensor integrates the microstrip antenna, the integrated circuit board and the shielding outer shell, and is high in sensitivity, small in signal distortion, good in signal-to-noise ratio characteristic, and capable of keeping characteristic information of partial discharge signals to the maximum limit.

The sending end buffers the waveform signals processed by subband filter banks; cutting off the streaking signals at the beginning and end of the buffer waveform to get the truncated signals; making the looping stack from beginning to end of the truncated signals to get the transmission signals of time domain looping from beginning to end.

The present invention includes 1, searching waveform in signal most similar with signal end point waveform and used as end point waveform estimation; 2, using outboard waveform in said most similar waveform as outer end point signal data estimation and continuing said waveform to outer signal end point. Said invention has advantages of high continuation data precision, eliminating end effect to both of circulation smoothness signal periodic signal and non-circulation smoothness signal.

The invention provides a refrigeration coaxial light-emitting pipe core, which comprises a TO (transmission optical) pipe shell and a sealing pipe cap with a light window. The TO pipe shell comprises a pipe shell base and a laser mounting sleeve connected with the pipe shell base in a sealing way, the pipe shell base is provided with a plurality of pins electrically connected with an external system, the inner sidewall of the laser mounting sleeve is provided with a mounting platform, a heat dissipating surface of a refrigerator is arranged on the surface of the mounting platform, a refrigeration surface of the refrigerator is used for the arrangement of a laser carrier, the surface of the laser is provided with an electro-absorption modulated n laser chip, a thermistor and a backlight detector, and the light-emitting optical axis of the laser chip is arranged coaxial with the central axis OA of the TO pipe shell and is output by the light window of the sealing pipe cap. Heat dissipation of the whole device is achieved by the laser mounting sleeve instead of the base of the traditional TO pipe shell, and the problem of laser cooling is solved. The pipe core with the structure is coupled with an external optical element of the TO pipe shell to manufacture the light-emitting component with the appearance complying with multi-source agreements XMD (Xilinx microprocessor debugger) for small devices of 10 Gb/s.

A computed tomography apparatus includes a two-dimensional data acquisition system which acquires projection data of a radiographic region within a subject using a multirow detector, and a hybrid image reconstruction system which reconstructs an image of the radiographic region on the basis of both the projection data and additional data calculated from the projection data. The hybrid image reconstruction system functionally includes a unit for calculating an additional intermediate beam data set, a unit for executing hybrid reconstruction of an oblique section, and a unit for generating a parallel section group. Owing to the construction, there are provided an image reconstruction method which is practicable and which affords a high precision, and a three-dimensional CT system which has the functions of the image reconstruction method.

The invention discloses a sampling hold circuit applied to an analogue-to-digital converter, which comprises a sampling switch bootstrap circuit (10), a sampling network (20) and a source follower (30). The output end of the sampling switch bootstrap circuit (10) is connected with the input end of the sampling network (20); the output end of the sampling network (20) is connected with the input end of the source follower (30); and a thirteenth node (13) of the source follower (30) is the output Vout of the sampling hold circuit. Compared with the conventional sampling hold circuit, the sampling hold circuit applied to the analogue-to-digital converter eliminates the nonlinearity of a switch conducting resistance, reduces signal distortion and improves the accuracy of the circuit due to theadoption of the bootstrap circuit.

The invention discloses a navigation anti-interference algorithm combining threshold processing and a space-frequency adaptive algorithm, and belongs to the field of satellite navigation communication. The algorithm enables a threshold processing algorithm and the space-frequency adaptive algorithm to be combined together, carries out the threshold preprocessing of a signal converted into a frequency domain at first, and then carries out the space-frequency adaptive processing, thereby effectively improves the capability of resisting narrow-band strong interference of an anti-interference system. Meanwhile, the algorithm employs a method of two-channel data stack windowing for the anti-interference processing of the signal during the space-frequency adaptive processing, effectively reducing the impact on spectrum leakage from a conventional space-frequency adaptive algorithm, and improving the performance of a system.

The invention discloses an automatic gain control device and an audio control system comprising the same. The automatic gain control device comprises an extraction unit, a first addition unit, a moving average filter, a locking circuit and an accumulator, wherein the extraction unit is used for carrying out power extraction on intermediate frequency signals, and acquiring a signal instantaneous power value; the first addition unit is used for subtracting the signal instantaneous power value from a target power value, and acquiring a signal instantaneous power difference value; the moving average filter is used for acquiring an average power difference value according to the signal instantaneous power difference value; the locking circuit is used for generating locking signals according to the average power difference value, and the locking signals are used for controlling the accumulator to be in a locking or unlocking state; and the accumulator is used for accumulating the average power difference value in the unlocking state, and outputting automatic gain control signals. The fidelity of steady signals is improved by additionally arranging the locking circuit to control the operation of the accumulator.

The present invention is provided with an audio signal amplifier circuit and an electrnic apparatus having same. The audio signal amplifier circuit includes a first, a second and a third differential amplifier which operate at a source voltage with respect to a reference voltage or a voltage between these; an output stage having a first and a second transistor driven complimentarily; a first resistor connected to an input terminal; a second resistor connected to an output of the first differential amplifier circuit; and a first and a second feed back resistor connected to an output terminal of the output stage circuit.

The embodiment of the invention discloses a carrier tracking loop and a receiver. The carrier tracking loop comprises a first feedback loop module and a second feedback loop module; the first feedback loop module is used for conducting frequency eliminating processing on first data by adopting received first frequency estimation values sent by the second feedback loop module; the second feedback loop module is used for conducting frequency adjustment on third data by adopting second frequency estimation values and demodulating the data subjected to frequency adjustment to obtain bit data. According to the carrier tracking loop, a double-feedback loop mechanism is adopted, the first feedback loop module conducts coarse frequency offset eliminating by adopting the first frequency estimation values and pulls signal Doppler frequency offset to be within the bandwidth range of a matched filter, and signal distortion caused by filtering is reduced; the second feedback loop module conducts precise carrier tracking by adopting the second frequency estimation values, so that a signal frequency spectrum can be stabilized within the main lobe range of the matched filter at every moment.

The invention discloses an OFDM peak-to-average ratio suppression method based on an alternating direction multiplier method for solving the problem that the existing optimization method for reducingthe OFDM peak-to-average ratio has high computational complexity. The implementation scheme comprises: taking frequency domain OFDM signal data carrier interference as an objective function, taking the peak-to-average ratio and the free carrier power as constraint conditions, establishing a non-convex optimization model; using the alternating direction multiplier ADMM to participate in the optimization process, and seeking the optimal solution, wherein the optimization process consists of two schemes, the ADMM method is directly used for solving in scheme 1, and a KKT point of an optimizationmodel can be guaranteed to be converged in the case of convergence. In the scheme 2, the optimization model is relaxed to obtain a relaxation model to guarantee the convergence, and the KKT point of the optimization model is infinitely approached in the case that the parameters are properly selected. Compared with the existing peak-to-average ratio suppression method, the OFDM peak-to-average ratio suppression method has the advantages of being able to obtain a smaller and more constant peak-to-average ratio, improving the system error rate performance and reducing the computational complexity, and the OFDM peak-to-average ratio suppression method is applied to the technical field of communication to improve the transmission quality of the communication system quality.

The invention relates to a noise removing method for contact net insulator leaked currents. According to the method, an extreme value prolongation method is used for reducing end point effect, signals are resolved through an improved EMD method so as to obtain components of frequency from high to low, a power ratio method is used to remove false components, noise in high-frequency ingredients in the remaining components is removed in a small wave threshold mode, and high frequency signals after noise removing and the remaining components are reconstructed, so that signals after noise removing can be obtained. The EMD method has adaptivity compared with small wave conversion. The problem of base function selection does not need considering. Compared with the EMD method, the improved EMD threshold method reduces effect of end point effect and false components on noise removing effect. Further, threshold value noise removing is conducted on high-frequency components, useful signals can be maintained to a largest degree, and signal distortion is reduced.