17results about How to "Increased frequency range" patented technology

The invention provides Yb2Si2O7-BaSrAlSiO / TiO2nws composite ceramic as well as a preparation method and application of the Yb2Si2O7-BaSrAlSiO / TiO2nws composite ceramic, and solves the problems of the existing microwave absorption ceramic. The Yb2Si2O7-BaSrAlSiO / TiO2nws composite ceramic is prepared by adopting a cold pressing method according to a research and development path of introducing TiO2nws and BaSrAlSiO on the basis of Yb2Si2O7 ceramic, and the ternary ceramic, namely the Yb2Si2O7-BaSrAlSiO / TiO2nws composite ceramic, which is adjustable in dielectric constant and electromagnetic wave absorption characteristic and has different energy gaps and structural properties can be realized by changing the mass ratio of raw materials.

The invention discloses a valley voltage detection holding circuit and a constant on-time control system, and relates to the field of analog integrated circuit design, and the circuit comprises a sampling circuit which samples an input power supply and sends a sampling signal to a control circuit; the control circuit is used for detecting the valley voltage of the sampling signal and controlling and maintaining the valley voltage; and the filter circuit filters the high-frequency part of the output voltage. Meanwhile, the circuit is adopted and used in a circuit system based on a COT control mode, a traditional ripple compensation technology is optimized by detecting valley voltage holding, the problem that when the capacitor ESR is small, a traditional COT control step-down converter causes phase lag due to output voltage change, and subharmonic oscillation can be generated is solved, and the voltage-reducing effect of the COT control step-down converter is improved. And the problem that the voltage output precision is reduced due to the introduction of bias voltage in the traditional ripple compensation technology is solved.

The application discloses a kind of acquisition methods for the acoustic transfer characteristics of a through-hull piping system, which comprises the following steps: obtaining the acoustic transfer characteristics of the piping system in the frequency range of 5Hz-1st critical frequency, drawing the relationship curve, and taking the 1st peak point on the curve; determining each high-order critical frequency, calculating and obtaining the relationship between the amplitude A of the peak point in the acoustic transfer characteristics relationship curve of the piping system and the frequency f; drawing the relationship curve between the amplitude of the peak point and the frequency, and determining the peak point of each frequency band on the curve, and calculating the acoustic transfer characteristics relationship of the corresponding peak point frequency band. The beneficial effects of the present application are: based on the traditional method, the peak point-frequency relationship of the acoustic transfer characteristics curve of the through-hull piping system is given, and an acquisition method for the acoustic transfer characteristics of the through-hull piping system is proposed, which can be used for the evaluation of the acoustic transfer characteristics of the system piping in the frequency band of 5Hz-1000Hz in the preliminary design stage of the through-hull system.

The invention discloses a fractional order circuit and a method for adjusting parameters of the fractional order circuit. The fractional order circuit comprises a signal processing circuit module, a negative voltage current source circuit module and a current sampling and displaying circuit module. The signal processing circuit module is used for receiving the adjusted bias current signal; the signal processing circuit module is also used for adjusting bias current values input into the N groups of operational amplifier circuits according to the adjusted bias current signals so as to adjust zero point values and pole point values of the N groups of operational amplifier circuits, so that the frequency range capable of meeting the fractional order property is enlarged; and / or, adjusting the proportion of the bias current values input into the N groups of operational amplifier circuits according to the adjusted bias current signals so as to adjust the amplitudes of the N groups of operational amplifier circuits, the supported external signal voltage range is enlarged; and the signal processing circuit module is also used for processing an external input signal according to the adjusted N groups of operational amplifier circuits to obtain an output signal, and the output signal is a signal meeting the fractional order property.

The utility model discloses a small-sized portable vibroseis device, which comprises a box body with an opening at the upper end and an accommodating space, a cover body is detachably arranged at the upper end of the box body, a servo motor is arranged in the accommodating space of the box body, a connector is arranged at the output end of the servo motor, and the small-sized portable vibroseis device further comprises three bevel gears, one end of the connector is connected with one bevel gear, the other two bevel gears are in transmission connection with the bevel gear connected with the connector, the other two bevel gears are connected with the eccentric parts respectively, and the servo motor drives the bevel gears to rotate so that the two eccentric parts can coaxially and reversely rotate. According to the utility model, the requirements of near-surface seismic exploration and small-area underground structure time-varying monitoring research can still be met while full miniaturization is carried out and the frequency of exciting the seismic source is improved.

The invention relates to a noise reduction method and device for an automobile multi-motor system, a storage medium and a vehicle. The method comprises the steps that when a first motor and a second motor are both in a running state, the noise frequency and state parameters of the first motor and the noise frequency and state parameters of the second motor are obtained; according to the specific frequency parts of the two motors, harmonic current acting on the other motor is generated in combination with the state parameters of the other motor; and for the common frequency part of the two motors, the phases of the first motor and the second motor on the common noise frequency are controlled to be opposite based on a conventional mode. Compared with the prior art, noise reduction is achieved through pairing of the two motors, the unique frequency and the common frequency are processed respectively, the frequency range capable of being subjected to noise reduction can be greatly widened, and then the vehicle noise is better reduced.

The invention discloses a dual-channel radio frequency conditioning device, which relates to the technical field of radio frequency microwaves and comprises a wave band switch, a first numerical control attenuator, a second numerical control attenuator, a preselection filter bank and a power divider, one end of the band switch is connected with the first input port and the second input port, the other end of the band switch is connected with one end of the first numerical control attenuator, the other end of the first numerical control attenuator is connected with one end of the preselection filter bank, and the other end of the preselection filter bank is connected with one end of the second numerical control attenuator. The other end of the second numerical control attenuator is connected with one end of the power divider, and the other end of the power divider is connected with the first output port and the second output port. According to the invention, input signals with different frequencies can be respectively output from different output paths through filtering gain, so that the frequency range of the output signals is enlarged. And meanwhile, the adaptability of the two channels in a practical application scene is improved.

The invention discloses a flow field conversion mechanism and a refrigerating machine with the same, and belongs to the technical field of refrigerating machines, the flow field conversion mechanism comprises a rotor part and a stator part, the rotor part is provided with a first counter bore and a second counter bore which are annularly distributed, the radial size of the first counter bore is larger than that of the second counter bore, and the stator part is provided with a stator. A first direct current counter bore communicated with the second counter bore is formed in the center of the rotor part; the stator part is provided with a first deep hole and a second through hole, the position of the first deep hole corresponds to the position of the proximal end of the first counter bore, the position of the second through hole corresponds to the radius position of the second counter bore, and the stator part is further provided with a first direct-current through hole matched with the first direct-current counter bore. The refrigerating machine comprises the flow field conversion mechanism, the flow field conversion mechanism serves as a middle structure of the refrigerating machine and a compressor, airflow exchange between the refrigerating machine and the compressor is achieved, and direct-current airflow is converted into alternating airflow to be supplied to the refrigerating machine.

The present invention is applicable to the technical field of household electrical appliances, and provides a noise reduction device and a clothing processing device. The noise reduction device comprises a main body, and a first cavity and a second cavity that are not directly connected are arranged at both ends of the main body; a sound absorbing member is sleeved on the outside of the main body; wherein an annular flow channel is formed between the main body and the sound absorbing member, and the annular flow channel is respectively connected to the first cavity and the second cavity. The clothing processing device comprises the noise reduction device, a fan and a fan sound insulation assembly. The noise reduction device adopts a first cavity and a second cavity that are not directly connected to each other that are arranged at both ends of the main body, and the first cavity and the second cavity are connected by setting an annular flow channel. In this way, the contact area and contact time between the noise and the sound absorbing member are increased, which is conducive to the sound absorbing member to better play the role of sound absorption and noise reduction, so that the noise generated by the clothing processing device during actual use is effectively reduced, and the user's comfort is improved.

The present application relates to a shrapnel and a vibrator using the shrapnel, which includes a rigid shrapnel body and a damping diaphragm, wherein the damping diaphragm is compounded on the rigid shrapnel body, the rigid shrapnel body is used for bone conduction, and the damping diaphragm is used for air conduction. The damping diaphragm is compounded on the rigid shrapnel body to achieve the integration of bone conduction and air conduction. It can make sound through bone conduction vibration and through the damping diaphragm at the same time, reflecting the frequency response below 200HZ and above 3KHZ that the existing shrapnel cannot perform well. On the basis of the working principle of the original bone conduction vibrator shrapnel, the structure of the vibrator shrapnel is changed to achieve the combination of vibrator vibration and traditional speaker air conduction sound. It can achieve both bone conduction speaker vibration sound and air conduction speaker diaphragm sound, increase the frequency response range of bone conduction headphones, improve the sound quality of traditional bone conduction vibrators, and also increase practical scenarios.

The invention relates to a bulk acoustic wave device (100) comprising a first electrode (1a) and a second electrode (2a) and a piezoelectric element (3a) arranged between the first electrode and the second electrode, the piezoelectric element being designed such that a first electromagnetic signal fed into the first electrode is converted into an acoustic signal in the piezoelectric element, the acoustic signal is inverted in the second electrode into a second electromagnetic signal. The piezoelectric element comprises at least two piezoelectric layers (31, 33) having polarity in the same direction and at least one intermediate layer (32a) between the at least two piezoelectric layers. The acoustic layer thickness of the piezoelectric layer and the acoustic layer thickness of the intermediate layer are respectively equivalent to odd times of the semi-acoustic wave length of an acoustic signal to be transmitted.

The invention discloses a DLL circuit, a control method and electronic equipment, and belongs to the technical field of electronic equipment. The DLL circuit includes a phase discriminator, a charge pump, a voltage-controlled delay line, and a processing unit. An annular oscillator in the voltage-controlled delay line carries out oscillation processing on an input clock signal and outputs an oscillation signal. Under the condition that the frequency of the oscillation signal does not meet the target frequency, the processing unit adjusts the load capacitance of the second delay unit of the ring oscillator until the target frequency is met, the ring oscillator is controlled to stop working, and the load capacitance of the first delay unit and the load capacitance of the second delay unit are equal to the load capacitance of the first delay unit in the voltage-controlled delay line. The voltage-controlled delay line delays an input clock signal and outputs a target clock signal. The phase discriminator outputs a phase difference signal according to the phases of the target clock signal and the input clock signal. The charge pump outputs a control voltage signal according to the phase difference signal. According to the invention, the adjustment range of the delay duration of the first delay unit is improved.

The invention discloses a front-end anti-interference system of a radio frequency receiver, and relates to the field of radio frequency anti-interference. The system comprises a power divider used for dividing a received antenna signal into a first low-frequency signal and a first high-frequency signal; the low-frequency signal processing module is used for receiving and preprocessing the first low-frequency signal and then outputting a third intermediate-frequency signal; the high-frequency signal processing module is used for receiving and preprocessing the first high-frequency signal and then outputting a fourth intermediate-frequency signal; and the combiner is used for receiving the third intermediate-frequency signal and the fourth intermediate-frequency signal and combining the signals into one path for output. Compared with the prior art, the preprocessing processes of the low-frequency signal and the high-frequency signal do not interfere with each other, the sensitivity and the anti-interference capability of the radio frequency receiver are improved, the frequency band range of the radio frequency signal preprocessed at the front end of the radio frequency receiver is enlarged, and feeder lines are saved.

A transducer structure (100) for an acoustic device comprising a piezoelectric layer (104), a pair of inter-digitated comb electrodes (108, 110), comprising a plurality of electrode means (112_1, 112_2, 112_3, 112_4, 114_1, 114_2, 114_3, 114_4) with a pitch p satisfying the Bragg condition given by p= lambda / 2, lambda being the operating acoustic wavelength of said transducer, characterized in that the inter-digitated comb electrodes (108, 110) are embedded in the piezoelectric layer (104) and the acoustic impedance of the electrode means is less than the acoustic impedance of the piezoelectric layer such that, in use, the excitation of a wave propagating mode in the volume of the electrode means is taking place and is the predominant propagating mode of the structure. The invention relates also to a acoustic wave device comprising at least one transducer structure as described above and to a method for fabricating said transducer structure. The invention relates also to the use of the frequency of the bulk wave propagating in the electrode means of said transducer structure in an acoustic wave device to generate contribution at high frequency, in particular above 3GHz.

The application provides a four-mode voltage-controlled oscillator, comprising four kernel units, one kernel unit is composed of two cores, and the whole is an eight-core structure, four different modes are generated to achieve a double-octave tuning range. The application benefits from a completely magnetically induced mode, which does not use additional capacitors, and finally realizes a high figure of merit (FoM) in the ultra-high frequency range, enhancing the frequency range of the PLL. The application is based on an eight-core four-mode wide tuning VCO structure of 8-shaped inductors, which skillfully uses the magnetic field coupling and inductance evanescent scheme to tightly couple the eight cores together, achieving super-multi-core and super-wide tuning range without losing additional area. It has a wider frequency adjustment range, smaller area and lower power consumption.

A body sound device comprising a first electrode (1a; 1b) and a second electrode (2a; 2b); and at least one first electrode (1a; 1b) and the second electrode (2a; 2b), said piezoelectric element (3) being designed in such a way that the piezoelectric element (3) is arranged between the first electrode (1a; 1b) is converted into an acoustic signal in the piezoelectric element (3), said acoustic signal being stored in the second electrode (2a; 2b) of the first electrode signal and the second electrode signal; comprising a further dielectric layer (7) surrounding the first electrode (1a; 1b), said second electrode (2a; 2b) and the piezoelectric element (3) and having a substantially flat surface; wherein at least one separating trench (11a; 11b) is formed in the dielectric layer (7); 11b) which at least partially surrounds the piezoelectric element (3).

The invention discloses a synchronous electric drive NVH optimization method, device and equipment and a medium, and the method comprises the steps: obtaining the reference frequency of a vehicle motor in a vehicle operation process, and judging whether the reference frequency is in a preset variable carrier frequency region or not; if yes, randomly generating a first random number, and determining a random carrier frequency according to the first random number, the reference frequency and a set carrier frequency change amplitude; according to the first random number, the random carrier frequency and a set carrier amplitude, determining a first loading slope of a first half period carrier and a second loading slope of a second half period carrier in a current carrier period to obtain a first carrier; and comparing the first carrier wave with a first modulated wave, and outputting an optimized PWM signal, the first modulated wave being generated according to the first carrier wave.