82results about How to "Low noise performance" patented technology

The invention provides a monolithic integrated three-axis accelerometer and a manufacturing method thereof so as to solve the defects in structure and manufacturing technology of the existing structural capacitive accelerometer. Three layers of metal Al thin films are deposited in the direction of an axis Z so as to form a comb pair sensitive electrode; four layers of metal Al / SiO2 thin films are deposited in the directions of an axis X and an axis Y so as to form comb pair sensitive electrodes, and the accelerations of the three axis directions are detected simultaneously by a single integrated structure. The accelerometer and the manufacturing method thereof have the following positive technical effects: the interconnection stray capacitance among accelerator devices in three axis directions is lowered remarkably, and high detection accuracy and lower noise performance are realized; since the accelerometer is provided with the multiple metal layers, compared with a microaccelerometer manufactured from the same material, namely polycrystalline silicon, the accelerometer is more flexible in wiring; a foldable beam is used in the structure of the accelerometer, so that the own stress of the accelerometer is released better, and therefore the influence of the stress on the system can be reduced effectively.

A sensor system is formed from a micro machined resonant structure with multiple resonant elements, a tracking resonator control electronics, and signal processing algorithms. The moving elements of the resonator are coated with chemically active materials that change mass when exposed to the target chemical resulting in a change in frequency or period of oscillation. The changes in frequency or period are processed by multi-sensor chemical detection algorithms to identify chemical types and concentrations. In essence, the resonator and drive electronics form a closed loop oscillator operating at the resonator's natural frequency. The resonators are formed from silicon using photolithographic processes. The resonator design includes in-plane resonant motion combined with dynamic balance to operate with a high Q even in the presence of atmospheric pressure.

A switchable gain amplifier for use in mobile communications devices is provided, having a first amplifier stage having a first gain, a second amplifier stage connected in parallel with the first amplifier stage. The first and second amplifier stage have different gains and a gain controller, connected to the first amplifier stage and to the second amplifier stage, enables only one of the amplifier stages at a time.

A flux locked loop for providing an electrical feedback signal, the flux locked loop employing radio-frequency components and technology to extend the flux modulation frequency and tracking loop bandwidth. The flux locked loop of the present invention has particularly useful application in read-out electronics for DC SQUID magnetic measurement systems, in which case the electrical signal output by the flux locked loop represents an unknown magnetic flux applied to the DC SQUID.

A CMOS differential power amplifier having broadband input matching with Noise and Non-linearity Cancellation. The broadband input match is realized by using two “Diode-Connected” NFETs (i.e., N-type Field Effect Transistors). Resulting noise degradation is reduced by using a noise cancellation structure. By using the same structure the disclosed method and apparatus also achieves non-linearity cancellation.

The present invention aims to improve the wet performance while securing steering stability and holding down degradations in noise performance to minimum, and for this purpose, a pneumatic tire in which blocks are disposed at intervals at a tread portion thereof is arranged in that concave blocks with stepped concave portions that extend along block side edges, which face circumferential main grooves, and having a depth from a block top surface that corresponds to 20 to 70% of a block height are provided. The concave portions have a length in a tire circumferential direction of 40 to 95% of a length of the block side edges in the tire circumferential direction and a width in a tire axial direction of 2 to 20 mm.

The invention discloses a bionic microporous noise-reducing structure which is used for an oil fume extraction system. The structure comprises a shell body; oil fume passes by the inner cavity of the shell body and contacts with the inner wall of the shell body; the invention is characterized in that the outer side of the shell body is fixedly provided with a noise-reducing box which is enclosed at the periphery; the noise-reducing box is internally provided with at least one layer of porous plate which is distributed with tight millipores, so the noise-reducing box is divided into at least an inner cavity and an outer cavity; the shell body which is opposite to the porous plate and enclosed in the noise-reducing box is coated and distributed with an oil-preventing coat, moreover, bar-shaped pores are tightly distributed on the shell body; the inner cavity of the shell body is communicated with the inner cavity of the noise-reducing box by the bar-shaped pores, moreover, the bar-shaped pores are slits of louver window type and the vanes of the slits are self-locked. The invention uses a principle of fluid mechanics for effectively preventing the oil fume from blocking the millipores at places such as cochlear duct, air exhaust pipe and the like, finally ensures that the noise-reducing box can effectively achieves the aims of long-term sound absorption and noise reduction, and is especially suitable for household oil fume extraction machine.

This invention relates to a self-restructing plasma antenna including a column container, inert gases, a RF excitation antenna, a RF excitation source, a signal coupler, a feeding port and an earth plate characterizing that the column container is filled with inert gases, the source and the antenna are used in exciting and maintaining the plasma, in which, the excitation antenna is set in the inside or outside of the column container, its lead out wire is connected with the RF excitation source, the signal coupler is used to couple the signal to the plasma antenna set out of the container, the lead out wire is connected with the internal conductor of the feeding port and the outer conductor is connected with the earth plate.

An apparatus includes an operational amplifier and a plurality of capacitors coupled to an input terminal of the operational amplifier and configured to be selectively coupled to receive one of an input voltage signal and an output voltage signal of the operational amplifier.

The present invention belongs to the field of frequency synthesizer design in radio transceiver and relates to phase-locked loop frequency synthesizer with digital coarse tuning loop. The frequency synthesizer includes a phase-locked loop comprising phase discriminator, loop filter, voltage-controlled vibrator and N frequency divider and a coarse tuning loop comprising the voltage-controlled vibrator, the N frequency divider and digital coarse tuning module. The present invention uses one groups of fixed capacitors to constitute partial variable capacitor and controls the amount of the resonant capacitance digital to tune the VCO output frequency. The present invention can compensate the manufacture error of integrated inductors and variable capacitor tube in chip, reduce the frequency synthesizing locking time, reduce VCO phase noise, reduce the capacitance in loop filter.

The invention discloses a hydraulic-motor piston pump with the purpose that electric energy is transmitted to hydraulic energy directly by machine winding directly driving cylinder body connected integrally with motor rotor. Motor stator 8, in which machine winding 7 and motor rotor 20 are set, is set in pump shell 5, rotor bar 10 is uniformly set in motor 20, on the two sides of motor rotor end face there are two end ring 9, the cylinder body 12 is set in the inner hole of motor rotor 20, inlet 18a is opened on right pump cap 18, outlet 1a is opened on left pump cap 1, multiple pistons 13 is uniformly set in pump shell 5, the piston 13 is tightly contacted with the bevel 18b of right pump shell 18 by slipper 15, return disc 14, ball hinge 16 and retracting spring 19.

The invention particularly relates to an oil-free vortex air compressor which comprises a rack, a static disc, a movable disc, a shaft sleeve, a crankshaft and pin cranks. The static disc is installed in the mode of being matched with the end face of the rack. The movable disc is installed in the mode of being matched with the end face of the shaft sleeve and located in the rack. A pin crank bearing at one end of each pin crank is installed on the rack, and a pin crank bearing at the other end of each pin crank is installed on the shaft sleeve. The shaft sleeve and the at least three pin cranks are restrained. The static disc and the movable disc driven by the crankshaft form a sealing cavity in continuous suction, compression and exhaust working states. Movable disc fins of a step type are arranged on the back of the movable disc. The shaft sleeve of a step type is installed on the movable disc fins. Clearance is reserved between all the bearing pedestal positions on the shaft sleeve and the movable disc fins. The air compressor has the advantages that the movable disc fins are utilized for being distributed on the back of the movable disc in a ladder shape, on the condition that the total length of the movable disc and the total length of the shaft sleeve is not changed, the heat dissipating area of the back of the movable disc is effectively increased, and the cooling effect is further achieved.

The present invention aims to improve the wet performance while securing steering stability and holding down degradations in noise performance to minimum, and for this purpose, a pneumatic tire in which blocks are disposed at intervals at a tread portion thereof is arranged in that concave blocks with stepped concave portions that extend along block side edges, which face circumferential main grooves, and having a depth from a block top surface that corresponds to 20 to 70% of a block height are provided. The concave portions have a length in a tire circumferential direction of 40 to 95% of a length of the block side edges in the tire circumferential direction and a width in a tire axial direction of 2 to 20 mm.

A power transmission belt (20) comprising a body (11) comprising an elastomeric material and having tensile members (10) running in a longitudinal direction, the body having a pulley-engaging region (12) having a profile; the pulley-engaging region comprising a fibrous nonwoven fabric material (15); characterized in that the fibers of the nonwoven material comprise acrylic fibers. The acrylic fibers are preferably micro-fibers of less than about 1.5 dpf and having an average diameter of 13.5 microns or less and an average length of about 1 to about 10 mm. The nonwoven material may be commingled with the elastomeric material in the pulley engaging region. Up to about 75% by weight of the fibers of the nonwoven material may comprise non-acrylic fibers such as other synthetic fibers, naturalfibers, or cellulosic fibers.

The invention discloses a vehicular radio control method and device, a vehicular radio and a vehicle; wherein the device comprises a monitoring module for creating a monitoring thread so as to monitor RSSI (Received Signa Strength Indication) information and SNR (SIGNAL-NOISERATIO) information of a current geographic position; an analyzing and smoothing module for analyzing and smoothing the RSSI information and the SNR information, thus obtaining smooth RSSI parameters and smooth SNR parameters; a radio quality parameter determining module for determining the integral radio quality parameter of the vehicular radio according to the RSSI information and the SNR information; and a processing executing module for judging whether the integral radio quality parameter is more than a set threshold value and reducing the playing volume of the vehicular radio if the integral radio quality parameter is more than the set threshold value. According to the method, the device, the vehicular radio and the vehicle provided by the invention, the integral radio quality is judged according to the RSSI and the SNR, and therefore, the playing volume of the radio is adjusted according to the set threshold value, thus reducing noises.

The invention discloses an ice condensation resistant ultra-thin wearing course pavement and a preparation method thereof. The ice condensation resistant ultra-thin wearing course pavement is prepared from the following raw materials in parts by weight: 15-17 parts of 10-15 mm gravels, 14-16 parts of 5-10 mm gravels, 11-13 parts of stone chips of which the particle size is smaller than 3 mm, 3-5 parts of ice condensation resistant agents, 2.2-2.6 parts of modified asphalt, and 1.1-1.4 parts of polymer modified emulsified asphalt, wherein the content of sodium chloride in the ice condensation resistant agents is 50-60%, and the solid content of the polymer modified emulsified asphalt is greater than or equal to 65%. According to the invention, ice condensation resistant ultra-thin wearing courses are paved on the pavement, so that the ice point of water in the surface of the pavement is reduced, snow accumulation and icing on the pavement are delayed, a new solution is put forward for solving the problem of the congelation of the pavement in winter is restrained, and safe running on the pavement is ensured.

The invention provides a low-cost and high-precision ku / ka multi-band satellite tracking control system. The system comprises a main reflecting surface, a secondary reflecting surface, a ku band feed device, a ka band feed device and a support device. A new tracking mode is employed, under the condition that the tracking precision is kept unchanged, the number of feed networks is reduced, the volume and weight of the whole structure are reduced, and the cost is reduced.

The invention discloses a distortion and noise cancellation based high-linearity CMOS broadband low noise amplifier. The distortion and noise cancellation based high-linearity CMOS broadband low noise amplifier structurally comprises a distortion cancellation input stage and a noise cancellation output stage. The distortion cancellation input stage serves as a first stage of the low noise amplifier, input impedance matching and second-order cross modulation IMD2 cancellation are achieved by adopting CMOS complementary common-gate combination, meanwhile a complementary structure has the characteristic of current reuse, and accordingly power consumption is reduced. The noise cancellation output stage serves as a second stage and is mainly used for cancelling channel thermal noise current of two common-gate devices at the first stage and accordingly reducing the noise coefficient of a whole circuit. The distortion and noise cancellation based high-linearity CMOS broadband low noise amplifier can simultaneously achieve high linearity and low noise coefficient within a broadband range, and meanwhile gives consideration to other design parameters, such as input impedance matching, power gain and power consumption.

The present invention relates to a fan shroud assembly and, more specifically, to a fan shroud assembly comprising: vortex-preventing saw-teeth which are arranged along a predetermined inner circumferential surface of a ventilating unit so as to maintain a predetermined gap with a blade end part or a band end part of a fan, and which are formed in a saw-toothed shape, wherein both a first area in which the vortex-preventing saw-teeth are formed and a second area from which the vortex-preventing saw-teeth are removed are formed, thereby generating vortexes of ventilated air due to a reduction in pressure fluctuation and thus effectively reducing noise.

The invention provides an all-optical caching method for realizing an orthogonal mode in a four-wave mixing mode. The all-optical caching method comprises the following steps of: inputting a modulatedoptical signal into a duplicator by adopting a pump; generating idler frequency light according to a frequency formula by means of a first four-wave mixing module; determining the sequence length ofall waveforms entering a cache region in a time domain by means of an input switch; after the signal enter the cache, injecting a pump signal into a recovery unit in a lower branch locking process, meanwhile, guiding signal waves and idler frequency waves to an upper branch, and carrying out phase and polarization adjustment; after upper and lower branches are combined, inputting PSA for signal compensation; and when buffering is not needed any more, activating an output switch and outputting an optical signal, and using a modulator in a pumping recovery branch circuit to adjust the relative phase and the pumping power, so as to realize empty or write-in operation on an optical buffer. According to the all-optical caching method, a duplicator type phase-sensitive amplifier is adopted, so that amplification of lower noise can be realized, multi-wavelength cache time control is realized, and the stability and transmission quality of a transmission system are improved at the same time.

The invention relates to a scroll compressor with an injection channel, in particular to an injection channel and noise reduction structure of the scroll compressor, which belongs to the technical field of scroll compressors. A motor stator is fixedly installed at the lower part in a housing, a motor rotor is installed in the motor stator, and the motor rotor is installed at the bottom of a crank shaft; an upper support and a movable scroll are installed on the crank shaft, a cross ring is installed between the movable scroll and the upper support, and a stationary scroll is fixed on the upper support; the stationary scroll is fitted with the movable scroll to form a plurality of compressed cavities, and an upper cover covers on the housing. The scroll compressor with the injection channel has the characteristicsis characterized in that a valve plate is installed on the stationary scroll through a bolt hole on the valve plate and a screw, the valve plate is provided with a main ejection channel and an ejection channel communicated with the main ejection channel, a through channel which is communicated with an ejection port on the stationary scroll is arranged at the lower part of the ejection channel, a groove is arranged at the lower part of the valve plate and encloses the stationary scroll to form a space, and an ejection pipe is installed on the main ejection channel.

The invention provides a nanopore gene sequencing micro-current detection device. The device comprises a detection circuit for current change when DNA molecules flow through a nanopore channel in a thin film, wherein the detection circuit comprises a first electrode, a second electrode, a third electrode and a constant potential circuit; and when a working electrode deviates, the constant potential circuit enables the ground potential of a counter electrode to change along with the ground potential of a reference electrode all the time, so that a stable voltage difference is kept between the first electrode and the second electrode. The invention further relates to a compensation method for nanopore gene sequencing micro-current stability. According to the invention, a current signal detected by the working electrode is changed into a voltage signal through an integral amplifier, the integral amplifier takes a capacitor as a feedback element, and two sampling and holding circuits are adopted to realize related double sampling, so that the noise performance is lower, and the bandwidth and the linearity of the signal are improved; meanwhile, the current signal is also subjected to filtering, denoising, compensation and other processing, so that the current detection accuracy is greatly improved.

Receivers for diversity reception of data transmitted by concatenated convolutional code (CCC) from at least one 8-VSB transmitter are described. Each receiver includes a first turbo decoder for the CCC as finally transmitted, a second turbo decoder for the CCC as initially transmitted, and an information-exchange unit connected for exchanging decoding information between the turbo decoders, which perform decoding concurrently. The turbo decoders are designed for decoding CCC formed from an outer convolutional code encoding de-interleaved Gray-coded data and a subsequent binary-coded inner convolutional code forming a 12-phase trellis code in accordance with a Gray-labeling procedure, the outer convolutional code encoding being symbol-interleaved before encoding within said inner convolutional code so said inner convolutional code has implied symbol interleaving in which the original order of data bits is preserved.

A communications cabling front-end architecture that achieves solid echo cancellation and lower noise performance by combining an echo-cancellation circuit and an equalizer function at the same point, at the most front-end of the system.

The invention provides a pneunatic tyre which prevents water discharging performance and improves uneven wear resistance and noise performance. The tire tread is provided with a central main groove in an equatorial plane of the tire, a pair of central auxiliary grooves at two sides of the central main groove, and a pair of tire shoulder main grooves at two sides, thereby forming central landing parts, middle landing parts and tire shoulder landing parts. Each middle landing part is provided with middle transverse grooves which are separately arranged in a circumferential direction and respectively extend from the central auxiliary groove to the tire shoulder main groove in an angle beta in 10-20 DEG. Each middle transverse groove is composed of a large-width part which is connected with the central auxiliary groove, a small-width part which is connected with the tire shoulder main groove, and a transition part which connects the large-width part with the small-width part. The angle beta of the middle transverse groove is larger than the angle alpha of the grounding front edge part of the middle landing part in the shape of a grounding surface.

The invention discloses a high-toughness, durable and antiskid steel bridge deck pavement structure and a construction method thereof. The steel bridge deck pavement structure comprises a steel bridgedeck steel plate; a bonding bottom layer, a buffer layer, an adhesion layer and a wearing layer are sequentially laid on the surface of the steel bridge deck steel plate from bottom to top; the buffer layer and the wearing layer are both made of high-toughness modified asphalt concrete composed of aggregate, filler and asphalt cement, the thickness of the buffer layer is 1-3 cm, and the thicknessof the wearing layer is 2-3 cm. The bridge deck pavement structure has good high-temperature rut resistance, fatigue durability, skid resistance, bonding strength and deformation compliance, comparedwith epoxy asphalt concrete, the engineering cost is greatly reduced, the construction process is simple, and later maintenance is convenient.

The invention discloses an air deflector and an air conditioner. The air deflector is applied to the air conditioner, the air deflector is a wing type air deflector, the wing type air deflector comprises a first end facing the inner side of an air outlet and a second end facing the outer side of the air outlet when the air outlet of the air conditioner performs air outlet work, and the area of thecross section of the air deflector is gradually reduced from the first end to the second end. According to the air deflector and the air conditioner, the air deflector is arranged to be of the wing type structure, so that the flow guide effect of the air deflector is guaranteed, meanwhile, the air volume loss can be reduced, the flowing state of airflow flowing through the air deflector is improved, the noise performance is guaranteed, flowing separation generated on the surface of the airflow when the airflow passes through the air deflector under the small-flow working condition is improved, and the condensation risk is reduced.