14results about How to "Reduce nonlinear distortion" patented technology

The invention provides a linearization circuit and a power amplifier, the linearization circuit comprises an impedance adjusting circuit, a first input end of the impedance adjusting circuit is used for accessing a first control signal, and a second input end of the impedance adjusting circuit is used for accessing a first radio frequency signal. A third input end of the impedance adjusting circuit is used for accessing a second radio frequency signal; each of the first control signal, the first radio frequency signal and the second radio frequency signal comprises a direct current component; the value of voltage accessed to the second input end of the impedance adjusting circuit changes along with the change of the first radio frequency signal, and the value of voltage accessed to the third input end of the impedance adjusting circuit changes along with the change of the second radio frequency signal, so that the impedance of the impedance adjusting circuit is dynamically adjusted. The linearization circuit provided by the invention can compensate the nonlinear distortion of the power amplifier so as to improve the quality of a radio frequency signal.

The utility model discloses a headrest loudspeaker, and relates to the technical field of loudspeakers. The headrest loudspeaker comprises a loudspeaker system and a shell system, the shell system comprises a front balancer, a basin stand and a rear shell which are fixedly connected in sequence, and the middle of the basin stand is hollowed out and used for containing and installing the loudspeaker system; and a sealed independent sound cavity structure is formed among the loudspeaker system, the basin frame and the rear shell. According to the headrest loudspeaker provided by the embodiment of the invention, the acoustic performance of the loudspeaker system can be optimized, the vibration subsystem in the loudspeaker system can be protected and the frequency response of the loudspeaker can be improved while no additional space is occupied, so that the sound effect of a vehicle-mounted sound system and the riding experience of a driver and passengers can be improved.

The present invention provides a method, system, device and medium for reducing high PAPR waveforms in radio frequency power amplifiers, the method comprising dividing an input high PAPR waveform into two sub-waveforms with lower PAPR; using two independent radio frequency power amplifiers to respectively amplify the sub-waveforms, wherein the sub-waveform received by the first radio frequency power amplifier is a sub-waveform with a PAPR reduced by 6dB compared with the original waveform, and the second radio frequency power amplifier receives a sub-waveform with a fixed amplitude; synthesizing the amplified sub-waveforms output by the two radio frequency power amplifiers to obtain a synthesized waveform. The present invention can improve the performance of radio frequency power amplifiers, optimize signal transmission, reduce costs, and improve the performance of the overall communication system.

A current decoupling control method for an auxiliary inductor dual-buck half-bridge power amplifier relates to the field of precision motor drive. The present invention controls the magnitude of the average current flowing through the auxiliary inductor to balance the current passing through the filter inductors on the two branches, thereby reducing the output current pulsation and further reducing the loss. The magnitudes of the currents in the two branches are set to constant values, so that the two branch currents output a half-cycle sine wave, and the branch output current does not pass through the zero point, thereby reducing the switching loss and harmonic distortion. The topological method of auxiliary increase in inductance can reduce the total inductance volume of the loop, and improve the problem of large inductance volume and weight caused by the DC bias magnetization of the inductor caused by the bias current. In addition, the auxiliary inductor current is added to the bias current of the loop, thereby reducing the nonlinear distortion of the system. The present invention improves the disadvantage of large inductance volume in the traditional dual-buck half-bridge inverter circuit loop, reduces the cost, and reduces the harmonic distortion of the circuit.

The invention belongs to the technical field of electronic equipment, and particularly relates to a digital-to-analog conversion control voltage variable LDO (Low Dropout Regulator) based on current negative feedback, which comprises a digital bit control DAC (Digital-to-Analog Converter) module, an error amplifier, an mos (Metal Oxide Semiconductor) tube, feedback resistors R1 and R2 and feedback capacitors C1 and C2, output current of the digital bit control DAC module is connected with a reverse input end of the error amplifier, a positive input end of the error amplifier is externally connected with reference voltage, and an output end of the error amplifier is connected with a grid electrode of the mos tube; a drain electrode of the mos tube is externally connected with power supply voltage, and a source electrode of the mos tube is connected with one ends of the R1, the R2, the C1 and the C2 respectively; the other end of the R1 is respectively connected with the other ends of the C1 and the C2, and is connected with the reverse input end of the error amplifier; the other end of the resistor R2 is grounded. According to the invention, the change of gain can be reduced through current negative feedback, so that the system is more stable under different working conditions, and oscillation and nonlinear distortion are reduced.

The present application provides a sample-and-hold amplifier, a high-speed analog-to-digital converter, and an electronic device. The sample-and-hold amplifier, the high-speed analog-to-digital converter, and the electronic device provided by the present application are provided with a first-stage non-Foster circuit and a second-stage non-Foster circuit in the sample-and-hold amplifier. The first-stage non-Foster circuit and the second-stage non-Foster circuit use negative capacitance to offset the internal parasitic capacitance, so that the nonlinear distortion caused by the parasitic capacitance can be reduced and the linearity of the sample-and-hold amplifier can be improved. In addition, the first-stage non-Foster circuit focuses on providing preliminary gain and parasitic capacitance compensation to ensure that the circuit can effectively process the input signal and reduce the impact of non-dominant poles on the overall performance. The second-stage non-Foster circuit further optimizes the gain and stability, so that the sample-and-hold circuit as a whole can achieve faster stability.

A dual-drive double-sided sound-emitting loudspeaker, comprising a first vibration system and a first magnetic circuit system assembled into a first sound-emitting body, and a second vibration system and a second magnetic circuit system assembled into a second sound-emitting body; further comprising a common magnetic conductive plate, wherein the first sound-emitting body and the second sound-emitting body are symmetrically arranged with the common magnetic conductive plate as a symmetry plane. Furthermore, the first magnetic circuit system and the second magnetic circuit system are symmetrically arranged relative to the common magnetic conductive plate, the first vibration system is installed on the outside of the first magnetic circuit system, and the second vibration system is installed on the outside of the second magnetic circuit system. The double diaphragms vibrate to emit sound, and the sound pressure of the double diaphragms can be enhanced by guiding the cavity during assembly of the whole machine, thereby improving the sound. It is conducive to the linear design of speaker vibration, and it is easier to design to reduce nonlinear distortion; it is conducive to avoiding the noise caused by polarization anomalies in speaker vibration; it is conducive to avoiding wire break anomalies caused by mechanical fatigue, and improving product yield.

The utility model provides a heart type super low frequency loudspeaker, including box, built -in power amplifier module and digital audio processor, is provided with first cavity and second cavity who does not communicate each other in the box, installs two first bass unit and second bass unit who radiate to the front in first cavity, installs one third bass unit who radiate to the back in second cavity, through two acoustics completely independent cavity design, has eliminated the harmful acoustic coupling and pressure interference between front and back units physically, can realize deeper degree, purer sound energy suppression behind the sound box, has improved the ability of overcoming stage sound feedback and purifying stage environment, and the isolation of physical acoustics has avoided the intermodulation distortion produced between units through air medium, makes every unit can work linearly in its own cavity, can reduce the nonlinear distortion of system, improves the purity of tone.

This utility model discloses a miniature loudspeaker, including a diaphragm assembly and a voice coil. The diaphragm assembly includes a center mount, which includes a body. The body has downwardly bent extension arms on opposite sides, and the bottom of each extension arm has an outwardly bent mounting arm. The voice coil is fitted onto the mounting arm. This miniature loudspeaker ensures effective suspension depth of the voice coil in the magnetic gap, significantly improving magnetic field utilization, BL value, and BL symmetry, optimizing distortion. It also eliminates the need for a separate frame and its corresponding assembly process, achieving a balance between high performance and low cost. The voice coil is located outside the extension arms, allowing for a wider diaphragm surround, thereby improving the low-frequency acoustic performance of the miniature loudspeaker.

The invention relates to the technical field of analog integrated circuits, and discloses a high-flatness analog switch, which comprises a common signal input end, a common signal output end, a first switch group and a second switch group, and is characterized in that the first switch group is switched on or switched off under the control of a first group of clock signals, and the second switch group is switched on or switched off under the control of a second group of clock signals; the first switch group is used for being switched on or switched off under the control of a first group of clock signals, the second switch group is used for being switched on or switched off under the control of a second group of clock signals, and the first group of clock signals and the second group of clock signals have preset phase deviation in a time domain, so that when one group of clock signals is in a level jump state, the other group of clock signals are kept in a stable level state. According to the analog switch, the two parallel switch groups are respectively controlled by using the two groups of clock signals with phase deviation, and when one group of clock signals jumps, the other group of clock signals is kept stable, so that a stable signal path always exists at the output end, the voltage fluctuation at the switching moment of the switch is smoothed, and the signal flatness of the analog switch in a conducting state is improved.

The utility model provides a loudspeaker which comprises two sound production units which are arranged in an overlapped mode and are respectively a first sound production unit and a second sound production unit, each sound production unit comprises a vibrating diaphragm, and the vibrating diaphragm comprises an elastic film and a conductive layer which are arranged in an overlapped mode; the first supporting piece and the second supporting piece are arranged on the two sides of the vibrating diaphragm respectively, and the peripheral edge of the vibrating diaphragm is fixedly connected with the two supporting pieces respectively; the first back polar plate is arranged on one side, far away from the vibrating diaphragm, of the first supporting piece, and the second back polar plate is arranged on one side, far away from the vibrating diaphragm, of the second supporting piece; each back polar plate comprises a conductive polar plate and an electret material layer which are combined into a whole; the two electret material layers of each sound production unit are respectively stored with different charges, and the conductive layers of the two sound production units are respectively used for inputting alternating current audio electric signals. The loudspeaker provided by the utility model has the advantages of simple structure, high sensitivity, low distortion and the like.

This utility model relates to a planar magnetic headphone magnet unit with a magnetically conductive structure. It includes a diaphragm, a permanent magnet array, and a support frame. The permanent magnet array consists of multiple strip-shaped permanent magnets symmetrically distributed on both sides of the diaphragm. A magnetically conductive alloy with a permeability μ≥10 is fixedly disposed on the outer side of the non-working surface of each strip-shaped permanent magnet. 4 A soft magnetic material with resistivity ρ≥50μΩ·cm has a U-shaped semi-enclosed cross-section that matches the magnet profile; the magnetic alloy is 0.1-0.5mm thick and has a 0.05-0.2mm gap with the magnet. Optionally, a hollow design is adopted. By constraining the magnetic field diffusion, the magnetic flux density is increased by 18% and the uniformity by 40%. At the same time, the alloy coating reduces the magnet breakage rate by 80%, achieving a synergistic breakthrough in acoustic performance and mechanical reliability.

The invention discloses an anti-interference method and system for a broadband P-band receiving link, and the method comprises the steps: a variable broadband anti-interference filter adjusts a received working frequency band according to a needed frequency, filters out other signals except the corresponding working frequency band, obtains a primary filtering signal, and transmits the primary filtering signal to a second receiving circuit; the signal is sent to the narrowband anti-interference filter bank through the second receiving circuit; and the narrowband anti-interference filter bank filters other signals outside the specified narrowband region to obtain a target signal and sends the target signal to the third receiving circuit. By using the variable broadband anti-interference filter, the working frequency band can be increased, the influence of an interference signal on a post-stage circuit is reduced, and the anti-interference capability is enhanced. In the inter-pulse frequency hopping process, a narrow-band anti-interference filter bank is used for enhancing the anti-interference capability and reducing the influence of an interference signal on a post-stage circuit. By using devices such as a high-linearity amplifier and a high-linearity mixer, the range of a target signal in a linear region is expanded, and nonlinear distortion is reduced.