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

An antenna is constituted in which a variable capacitance capacitor portion Ct is connected between an antenna element and a ground. In the variable capacitance capacitor, a plurality of variable capacitance elements using a thin film dielectric layer whose dielectric constant is changed by a voltage applied are connected in parallel with regard to direct current component and in series with regard to high frequency component between an antenna-element-side terminal and a ground-side terminal. The capacitance change ratio of the variable capacitance capacitor that depends on the bias signal can be utilized to the maximum so as to perform impedance matching so that the electrical length of the antenna element is changed, and thus, the operating frequency can be changed. In addition, the antenna having small waveform distortion and intermodulation distortion, high power handling capability and low loss at high frequencies can be realized.

A manufacturing method for a wiring circuit board includes the steps of: forming a board on a surface of a metal layer directly or indirectly through an etching barrier layer; forming an insulating film on the surface of the metal layer; polishing the insulating film to an extent to which a top face of the bump is exposed; and forming a solder ball on the top face of the bump.

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.

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.

Provided is an antenna branching filter having a suppressed intermodulation distortion. The antenna branching filter (100) is provided with: an antenna terminal (Ant.); a first filter circuit (1) having a first pass-band; and a second filter circuit (2) having a second pass-band that does not include the first pass-band and that is a frequency band higher than the first pass-band. The antenna terminal (Ant.), the first filter circuit (1), and the second filter circuit (2) are connected at a first connection point (J1); the second filter circuit (2) is provided with vertically coupled resonator-type filter circuits (2A, 2B); resonators (3A, 3B) are inserted between the first connection point (J1) and the vertically coupled resonator-type filter circuits (2A, 2B); and low-frequency-bandpass circuits (4A, 4B) having a stopband at the second pass-band are inserted between the ground potential and second connection points (J2A, J2B), which are the connection points of the resonators (3A, 3B) and the vertically coupled resonator-type filter circuits (2A, 2B).

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.

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.

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 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 isprovided 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.