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 V_{p<sub2>1</sub2>},V_{p<sub2>2</sub2>}, . . . V_{p<sub2>n </sub2>}of the sampled input signal V(t) exceeding a clip value V_clip at times t₁, t₂, . . . t_n; and modifying the sampled input signal V(t) by weighting the n peaks V_{p<sub2>1</sub2>},V_{p<sub2>2</sub2>}, . . . ,V_{p<sub2>n </sub2>}exceeding the clip value V_clip 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, . . . a_n;t−t_{p<sub2>1</sub2>},t−t_{p<sub2>2</sub2>}, . . . t−t_{p<sub2>n</sub2>}), wherein a₁,a₂, . . . a_n are weight values corresponding to the n peaks V_{p<sub2>1</sub2>}, V_{p<sub2>2</sub2>}, . . . V_{p<sub2>n</sub2>}, and f(t−t_{p<sub2>1</sub2>},t−t_{p<sub2>2</sub2>}, . . . t−t_{p<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.

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 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.

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).

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 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.