38results about How to "Reduce intermodulation distortion" patented technology

In one aspect, a mixer that provides improved isolation between an input oscillator and a mixing cell. In another aspect, a mixer that includes circuitry operative to shape an input signal provided by a local oscillator.

This invention provides a voltage tunable filter comprising an input connection point, an output connection point, and at least one circuit branch electrically coupled to the input connection point and the output connection point and including a voltage tunable dielectric varactor electrically connected to an inductor. The voltage tunable filter can be one of a low-pass, high-pass, band-pass, or band-stop filter. The varactor can include built-in DC blocking capacitors.

The invention relates to a portable all-purpose otoacoustic emission detecting system which belongs to the field of otoacoustic emission signal detectors and is characterized by comprising a portable PC (Personal Computer), a USB (Universal Serial Bus) sound card, a miniature loudspeaker, a miniature radio, a preprocessing circuit and a power supply, wherein the miniature loudspeaker comprises two sounders which can respectively send out stimulating sounds capable of evoking a transient evoked otoacoustic emission signal and a distortion product otoacoustic emission signal, the portable PC is provided with a USB sound card sensitivity calibration module and a miniature loudspeaker sensitivity calibration module, the PC, the USB sound card and the miniature loudspeaker form a stimulating sound playing path, and the miniature radio, the preprocessing circuit, the USB sound card and the PC form an otoacoustic emission signal acquisition path. The invention realizes the integrated detection for the transient otoacoustic emission signal and the distortion product otoacoustic emission signal and simultaneously realizes the portability of the all-purpose otoacoustic emission signal detecting system.

A system and method for frequency conversion in a frequency-conversion receiver is disclosed. The frequency-conversion receiver receives input RF signals carrying multiple channels. The frequency-conversion receiver converts the input RF signals to a wide IF band. The IF band is further processed by dividing the IF band into one or more frequency segments or by selecting a wideband frequency segment from the IF band. The wideband frequency segment or the one or more frequency segments are further down-converted, filtered and amplified to provide desired output IF signals, based on the number of channels required in the output IF signals.

The present invention relates to a tunable circuit, or admittance, arrangement comprising at least one capacitive branch with at least a tunable first capacitor, and tuning application means. It further comprises at least one resonant branch comprising at least a second capacitor and an inductor, said second capacitor and said inductor being connected in series. Said at least one capacitive branch and said at least one resonant branch are connected in parallel, and said tuning application means are adapted for application of a DC tuning voltage. The capacitance of said first and / or second capacitor and / or the inductance of said inductor are selected such that the frequency dependency of the tunability of a varactor arrangement forming the equivalent varactor arrangement of the admittance arrangement can be controlled at least in a selected frequency range.

A method and apparatus for reducing intermodulation distortion is disclosed. In one embodiment, the method comprises the steps of accepting a sampled input signal V(t) wherein the input signal V(t) comprises a plurality of peaks; determining n peaks Vp<sub2>1< / sub2>,Vp<sub2>2< / sub2>, . . . Vp<sub2>n < / sub2>of the sampled input signal V(t) exceeding a clip value Vclip at times t1, t2, . . . tn; and modifying the sampled input signal V(t) by weighting the n peaks Vp<sub2>1< / sub2>,Vp<sub2>2< / sub2>, . . . ,Vp<sub2>n < / sub2>exceeding the clip value Vclip of the sampled input signal V(t) by a function b(t) wherein b(t) is either a hard limiting function or b(t)=f(a1, a2, . . . an;t−tp<sub2>1< / sub2>,t−tp<sub2>2< / sub2>, . . . t−tp<sub2>n< / sub2>), wherein a1,a2, . . . an are weight values corresponding to the n peaks Vp<sub2>1< / sub2>, Vp<sub2>2< / sub2>, . . . Vp<sub2>n< / sub2>, and f(t−tp<sub2>1< / sub2>,t−tp<sub2>2< / sub2>, . . . t−tp<sub2>n< / sub2>) is a smooth shaping function. Intermodulation performance is then selectively improved in selected sub-bands by notch filtering prior to application to the non-linearity.

The invention provides a stereoscopic displaying apparatus which reduces the intermodulatino distortion. In the stereoscopic displaying apparatus which comprises an image generating region, a polarizing plate and a polarization axis control plate, the polarization axis control plate includes: a right eye polarizing region on which a right eye image light is incident; a left eye polarizing region which is arranged adjacent to the right eye polarizing region and on which a left eye image light is incident; a plurality of light blocking sections arranged on a plane facing the polarizing plate, each of which is a boundary between the right eye polarizing region, and the left eye polarizing region that blocks the right eye image light and the left eye image light; and a plurality of apertures formed between each of the plurality of light blocking sections that transmit therethrough the right eye image light and the left eye image light. The image light emitted from one of the right eye polarizing region and the left eye polarizing region and incident on one of the plurality of apertures goes to the inside of the angle of field while the image light emitted from the other of the right eye polarizing region and the left eye polarizing region adjacent to each other and incident on the one aperture goes to the outside of the angle of field.

Reduction of intermodulation distortion in a high-frequency switch is achieved. A semiconductor device (1) includes an antenna terminal (ANT_LB), plural external terminals (RX_LB, TX_LB, TRX_LB, TERM_LB), plural first high-frequency switches (101 to 104), and plural control terminals. Each first high-frequency switch includes plural first field-effect transistors, plural first resistors (Rg—1 to Rg—6) connected to the gate terminals of the first field-effect transistors, and a second resistor (Rc) disposed between the corresponding control terminal and the first resistors. The second resistor in the first high-frequency switch disposed between the first terminal supplied with an RF transmission signal and an RF reception signal of a frequency division duplex system and the antenna terminal is configured so that linearity of current-voltage characteristics thereof is higher than linearity of current-voltage characteristics of the first resistor.

The invention discloses an improved power amplifier lookup table predistortion method. According to the method, an input signal is supposed to be a stationary random signal, so the distribution of the statistical property of the input signal is defined and known; before the input signal enters into a power amplifier, predistortion treatment is performed on the input signal through a lookup table opposite to the non-linear characteristics of the power amplifier, and then, the predistortion signal after the predistortion treatment is sent to the power amplifier to enable an entire concatenated system to be linear. Construction of the lookup table is to uniformly distribute units for subsections of the lookup table by utilizing the distribution of the statistical property of the input signal and the nonlinear degree of all section signals provided by the invention.

The invention relates to a MC5G-type bundle RF coaxial connector. Multiple single-pin connectors and single-jack connectors are integrated into a multi-pin connector and a multi-jack connector respectively. Multiple connectors can be quickly connected or disconnected simultaneously at one time. A profiled positioning pin and a line sequence guide pin are matched with a profiled positioning hole. The outer portion of a multi-jack connector housing is in sealed connection with a multi-pin connector housing through a stopping bulge loop and a rectangular sealing ring. Each male outer conductor issimultaneously used as a plugging positioning guiding structure. The outer portion of each female outer conductor is in sealed connection with the corresponding male outer conductor through a stopping step and an O-shaped sealing ring. An elastic contact pieces having an open slot are embedded in each female outer conductor. A mechanical reference surface is separated from an electrical referencesurface. Each jack inner conductor is provided with an open slot extending from the front end surface toward the middle portion in the axial direction. The MC5G-type bundle RF coaxial connector is small in size, light in weight, convenient to operate, quick to install, suitable for medium-sized power, and low in intermodulation and reflection use requirements.

A liquid crystal display having a plurality of source lines in the display area which are each divided into two groups includes a first source driver for applying image signals to a first group of the divided source lines, a second source driver for applying image signals to a second group, a first gate driver operative to apply scanning signals to one segment of a plurality of gate lines that extends across the first group of the divided source lines, and a second gate driver for applying scanning signals to the other segment of a plurality of gate lines that extends across the second group of the divided source lines, and switching assemble.

An object of the present invention is to reduce the number of steps necessary for connecting between a wiring circuit board and a printed circuit board and to achieve a low-cost wiring circuit board. A wiring circuit board (2) includes an insulating film (4), a bump (6), an etching barrier layer (8), and a wiring layer (10). The bump (6) is made of copper and formed to penetrate through the insulating film (4). A top face of the bump (6) is exposed at a surface of the insulating film (4) flush therewith. The etching barrier layer (8) is made of nickel (Ni) and formed underneath the bump (6). The bump (6) is connected to the wiring layer (10) through the etching barrier layer (8). A solder ball (12) is formed on the top face of the bump (6). A printed circuit board (14) as a rigid board is connected to the wiring circuit board (2). A wiring layer (16) is connected to the bump (6) through the solder ball (12) to thereby mount the wiring circuit board (2) to the printed circuit board (14).

The invention provides a digital tuning stereo decoding method. The method has the following steps: setting a phase difference compensation circuit with symmetrical interior; replacing the prior stereo decoding difference signal generating circuit with the phase difference compensation circuit; decoding a stereo composite signal by a pair of quadrature subcarrier signals; processing the stereo composite signal by the phase difference compensation circuit, and sending the signal to a stereo mixer. The invention eliminates the phase effect of subcarriers, improves the stereo decoding performance, and optimizes the decoding performance.

A radio frequency circuit can transfer radio frequency signals used in first and second communication systems, and includes: a first transfer circuit that transfers a radio frequency signal having a frequency range in a first communication band having first transmission and receiving bands; and a second transfer circuit that transfers a radio frequency signal having a frequency range in a second communication band having second transmission and receiving bands. The radio frequency circuit can simultaneously transmit transmission signals having frequency ranges in the first and second communication bands using the first and second transfer circuits. The first receiving band is lower than the first transmission band, the first transmission band is lower than the second transmission band, and the second transmission band is lower than the second receiving band. The first and second transfer circuits are mounted on different mounting boards.

The invention provides a gesture action judgment method and device, electronic equipment and a storage medium. The method comprises the steps of obtaining an original audio signal which comprises an original ultrasonic signal and an original voice signal; acquiring nonlinear parameters of the loudspeaker; performing pre-distortion processing on the original audio signal according to the nonlinearparameters of the loudspeaker to obtain a pre-distortion signal; wherein the pre-distortion signal is transmitted to the loudspeaker, and the loudspeaker plays and generates a target output signal; wherein the target output signal is acquired by a microphone after being propagated by a space medium; acquiring an acquisition signal acquired by the microphone; and determining whether a gesture action exists or not according to the frequency spectrum characteristics of the original ultrasonic signal and the acquired signal. The gesture action judgment method is advantaged in that a problem of intermodulation distortion in gesture judgment processing by utilizing the ultrasonic signal can be reduced, and judgment precision of ultrasonic ranging and related applications by utilizing the loudspeaker in the device is remarkably improved.

The invention relates to a quick plug structure for a connector. When a male outer conductor is plugged into and matched with a female outer conductor, the rear end of the female outer conductor propsopen an elastic clamping ring, the elastic clamping ring enters a limit clamping slot in the outer circumferential surface of the female outer conductor, a right angle limit surface of the rear end of the elastic clamping ring is in fit with and limited by the limit clamping slot of the female outer conductor limit clamping slot and the rear side surface of a circular groove of the male outer conductor and can not exit; during disassembly, an unlocking sleeve is pulled to move backward along the outer surface of a limit boss, the edge of an annular inner ring props open the elastic clamping ring along an interior conical surface to exit from the limit clamping slot of the female outer conductor, and the female outer conductor can be disassembled after moving forward to exit. The quick plug structure for the connector has the advantages that size is small, weight is light, installation is quick, a connection operation is easy, coaxiality is good, quick plug can be realized, working efficiency is improved, and all the usage frequency band, intermodulation and power indexes respectively meet 5G communication using requirements.

The present invention provides a small-volume low-intermodulation RF connector. A male outer conductor is connected on a female outer conductor through a screw sleeve, the front end face of the male outer conductor is in conductive contact with a step on the inner hole of the female outer conductor to form a first conductive contact surface; a fixing section at the rear section of an elastic contact piece is inlaid in the male outer conductor, the elastic portion of the front section is extended to the outer portion of the male outer conductor to be in contact with the inner side circular conical surface of the female outer conductor to form a second conductive contact surface; radial and axial conductive contact surfaces achieve the intermodulation structure, the volume is small, the weight is light, the installation is fast, the connection operation is convenient, the coaxiality is good, the contact pressure of the inner and outer conductor interfaces are high, the reflection factorand the insertion loss are small, the crosstalk distortion is low, the anti-impact vibration performance is good, the outer conductor contact interface is reliable in seal, high in power and high in frequency band, and can be suitable for low-intermodulation requirements of 5G communication; and moreover, the raw material consumption of the copper conductor is reduced, the cost is reduced, and theintegration effect is good.

The invention belongs to the technical field of linear frequency modulation continuous wave radar ranging, and particularly relates to a linear frequency modulation radar ranging system and method based on distance. The system comprises a radar transmitter, an antenna, a receiver, a signal processing module, and a display. The receiver performs orthogonal demodulation on a received target echo signal and a transmitted signal to obtain a difference frequency signal, the difference frequency signal enters the signal processing module after being sampled, and distance measurement is realized through spectral analysis and processing. For a radar receiving system with the requirement for detecting far and near targets, the invention provides a segmented distance measurement scheme, which is beneficial to implementation on hardware, reduces intermodulation distortion of an amplifier and reduces the difficulty of signal processing. A common segmented distance measurement method is improved, multi-segment measurement is completed at a time, and the measurement speed is higher.

The invention discloses a high-power amplifier circuit based on D type amplification push and B type output and a working method thereof. A power amplifier circuit comprises a power amplifier circuit and a D type amplification push circuit; the D type amplification push circuit comprises a positive electrode D type amplification push circuit and a negative electrode D type amplification push circuit; the power amplifier circuit is connected with the positive electrode D type amplification push circuit and the negative electrode D type amplification push circuit; the positive electrode D type amplification push circuit comprises a signal acquiring circuit, a comparison circuit and a control circuit. The working method comprises the following steps: comparing signals by acquiring the signals, and outputting a control signal to control the output voltage of a power-supply regulating circuit. The technical scheme disclosed by the invention can enable the voltage at the output end of the power-supply regulating circuit to match with the power amplifier output voltage, the harmonic distortion and intermodulation distortion are lowered, the sound restoration capacity is improved so that the low pitch is more powerful and the high pitch is distortionless; the sound is bright, clear and powerful, and meanwhile, the energy consumption is small, and the calorific value is low.

An electron emitting element (10A) is provided with an emitter part (12) composed of a dielectric material, and an upper electrode (14) and a lower electrode (16) whereupon a driving voltage (Va) is applied for electron emission. The upper electrode (14) is formed on an upper plane of the emitter part (12), and the lower electrode (16) is formed on a lower plane of the emitter part (12). The upper electrode (14) is provided with a plurality of penetrating parts (20) from which the emitter part (12) is exposed. In the upper electrode (14), a plane facing the emitter part (12) at a circumference part (26) of the penetrating part (20) is separated from the emitter part (12).

The invention discloses a precise voice control sensor integrated control device. A charge control / output protection and output compensation controller is used for detecting voltage of a signal output end, detecting gate charge of an MOS (metal oxide semiconductor) transistor M1 and gate charge of an MOS transistor M2 and detecting voltage of a signal input end, signal output is compensated through an intelligent linear switch, and voltage of signal output is enabled to be within a set voltage range; or output is enabled to be zero or a switch K1 and / or a switch K2 is closed. The precise voice control sensor integrated control device has extremely high noise resistance, extremely wide voice rang, tiny distortion, extremely small size and extremely few ports; full-domain signal input is adopted, the variable-frequency intelligent linear switch is introduced in, the innovative charge algorithm control technique is adopted for charge control, output protection and output compensation control, further diodes, resistors and JFETs (junction field-effect transistors) adopted by the device are all special semiconductor processes, integration of a system is optimized fundamentally, and tiny size can be realized.

An electron emitting element (10A) is provided with an emitter part (12) composed of a dielectric material, and an upper electrode (14) and a lower electrode (16) whereupon a driving voltage (Va) is applied for electron emission. The upper electrode (14) is formed on an upper plane of the emitter part (12), and the lower electrode (16) is formed on a lower plane of the emitter part (12). The upper electrode (14) is provided with a plurality of penetrating parts (20) from which the emitter part (12) is exposed. In the upper electrode (14), a plane facing the emitter part (12) at a circumference part (26) of the penetrating part (20) is separated from the emitter part (12).

The present invention relates to a tunable circuit, or admittance, arrangement comprising at least one capacitive branch with at least a tunable first capacitor, and tuning application means. It further comprises at least one resonant branch comprising at least a second capacitor and an inductor, said second capacitor and said inductor being connected in series. Said at least one capacitive branch and said at least one resonant branch are connected in parallel, and said tuning application means are adapted for application of a DC tuning voltage. The capacitance of said first and / or second capacitor and / or the inductance of said inductor are selected such that the frequency dependency of the tunability of a varactor arrangement forming the equivalent varactor arrangement of the admittance arrangement can be controlled at least in a selected frequency range.

The invention discloses a broadband power amplifier circuit, comprising a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, a first triode, a second triode, a third triode, a fourth triode, a first inductor, a second inductor and an operational amplifier. The broadband power amplifier circuit has the advantages that the power amplification efficiency is high, the oscillation generated due to distributed capacitance feedback is effectively reduced, the amplification performance is stable, the intermodulation distortion is small, the harmonic distortion is small and the working frequency band range is wide; meanwhile, according to the broadband power amplifier circuit, the circuit structure is simple, fewer components are used, the manufacture cost is reduced, and a wide use value is obtained.

The invention discloses a high-power amplifier circuit based on D type amplification push and B type output and a working method thereof. A power amplifier circuit comprises a power amplifier circuit and a D type amplification push circuit; the D type amplification push circuit comprises a positive electrode D type amplification push circuit and a negative electrode D type amplification push circuit; the power amplifier circuit is connected with the positive electrode D type amplification push circuit and the negative electrode D type amplification push circuit; the positive electrode D type amplification push circuit comprises a signal acquiring circuit, a comparison circuit and a control circuit. The working method comprises the following steps: comparing signals by acquiring the signals, and outputting a control signal to control the output voltage of a power-supply regulating circuit. The technical scheme disclosed by the invention can enable the voltage at the output end of the power-supply regulating circuit to match with the power amplifier output voltage, the harmonic distortion and intermodulation distortion are lowered, the sound restoration capacity is improved so that the low pitch is more powerful and the high pitch is distortionless; the sound is bright, clear and powerful, and meanwhile, the energy consumption is small, and the calorific value is low.