30 results about "Constant noise" patented technology

Devices and methods are described for providing continuous measurement of an analyte concentration. In some embodiments, the device has a sensing mechanism and a sensing membrane that includes at least one surface-active group-containing polymer and that is located over the sensing mechanism. The sensing membrane may have a bioprotective layer configured to substantially block the effect and/or influence of non-constant noise-causing species.

Devices and methods are described for providing continuous measurement of an analyte concentration. In some embodiments, the device has a sensing mechanism and a sensing membrane that includes at least one surface-active group-containing polymer and that is located over the sensing mechanism. The sensing membrane may have a bioprotective layer configured to substantially block the effect and/or influence of non-constant noise-causing species.

Devices and methods are described for providing continuous measurement of an analyte concentration. In some embodiments, the device has a sensing mechanism and a sensing membrane that includes at least one surface-active group-containing polymer and that is located over the sensing mechanism. The sensing membrane may have a bioprotective layer configured to substantially block the effect and/or influence of non-constant noise-causing species.

Systems and methods of use involving sensors having a signal-to-noise ratio that is substantially unaffected by non-constant noise are provided for continuous analyte measurement in a host. In some embodiments, a continuous analyte measurement system is configured to be wholly, transcutaneously, intravascularly or extracorporeally implanted.

The invention relates to an active noise reduction system for an engine in an automobile. The system comprises two error microphones, five secondary sound source loudspeakers and one self-adaptation active controller. The two error microphones are arranged at automobile roof positions corresponding to a front row and a back row of the automobile. The five secondary sound source loudspeakers are composed of four vehicle-mounted loudspeaker boxes arranged on the automobile door sides and one secondary sound source arranged at the position of a rear row partition plate. The self-adaptation active controller comprises a DSP master control chip, an audio decoding chip, an off-chip storage unit, a CAN bus controller, a power amplifier, an error microphone signal receiving module, a secondary sound source output module and a power module. The invention further relates to an active noise reduction method for the engine in the automobile. By means of the system and method, error noise signals in active noise reduction reach the minimum value during constant noise reduction control, the noise influence caused by the error noise signals can be basically ignored, and the expected noise reduction effect can be rapidly achieved.

A simulation device of radio channel is prepared as setting said device at side of mobile station for carrying out multipath fading treatment on base band signal in order to simulate uplink and downlink channels as well as for superposing a power constant noise on multipath fading-treated signal when uplink channel is simulated.

A variable gain control amplifier (10) and method provides a substantially constant input impedance and output impedance, and provides a substantially constant noise figure and third order harmonic. The variable gain control amplifier (10) includes an amplifier stage including at least a first intermediate fixed gain stage (22) operative to produce a first intermediate signal (30) in response to the input signal (20). The variable gain control amplifier (10) further includes at least a second intermediate fixed gain stage (24) operative to produce an output signal (18) in response to the first intermediate signal (30). A feedback circuit (16) is operative to produce a gain control signal (32) in response to the output signal (18). A gain control circuit (26) is coupled to the at least first intermediate fixed gain stage (22) and the second intermediate fixed gain stage (24), and receives the gain control signal (32) to control an amplitude of the intermediate signal (30).

Systems and methods of use involving sensors having a signal-to-noise ratio that is substantially unaffected by non-constant noise are provided for continuous analyte measurement in a host. In some embodiments, a continuous analyte measurement system is configured to be wholly, transcutaneously, intravascularly or extracorporeally implanted.

A method for constructing a neural computing model for solving matrix equations, the formula of which is: A ( t ) X ( t ) · = - A · ( t ) X ( t ) + B · ( t ) - F ( A ( t ) X ( t ) - B ( t ) ) - G ( A ( t ) X ( t ) - B ( t ) + ∫ 0 t F ( A ( t ) X ( t ) - B ( t ) ) d t ) + W ( t ) Calculate the solved X(t) through this final formula, starting from any initial state X(0)∈Rn×m, which is equivalent to the state matrix of the time-varying theoretical solution, and each of their elements is a monotonically increasing odd activation function . The neural computing model for solving matrix equations of the present invention has the characteristics of converging to the theoretical solution of matrix equations in a limited time even under the pollution of noise (constant noise, random noise), and no matter what activation function is used, the present invention The invention can converge to the theoretical solution of matrix equations.

Systems and methods of use involving sensors having a signal-to-noise ratio that is substantially unaffected by non-constant noise are provided for continuous analyte measurement in a host. In some embodiments, a continuous analyte measurement system is configured to be wholly, transcutaneously, intravascularly or extracorporeally implanted.

In an electronic device for supplying DC power to an LSI chip (20), a distributed constant type noise filter (1) having an input port (2, 3) and an output port (5, 4) is fixed on a circuit board (6 )superior. The noise filter (1) reduces the ingress of high frequency noise while allowing DC power to flow through. The input ports (2, 3) are connected to a DC power line (7a) and a ground conductor (8a) on the circuit board (6). The output ports (5, 4) are connected with independent power supply conductors (7b) and independent ground conductors (8b), and the independent power supply conductors (7b) and independent ground conductors (8b) are fixed on the circuit board (6) The LSI (20) is connected. In another embodiment, the LSI (20) is fixed on another circuit board (17), and the output ports (5, 4) of the filter pass through conductor pins (18, 19) on the circuit board (6) Connect with another circuit board (17).

A Sigma-Delta ([Sigma][Delta]) modulator for converting an analog input signal having a frequency bandwidth around a variable center frequency f 0 to a digital output signal at a sampling frequency fs . The [Sigma][Delta] modulator comprises a quantizer (420) for generating the digital output signal and a loop filter for shaping the quantization noise. The loop filter comprises at least one subfilter (430, 410) centered around a frequency f0 and constant noise shaping coefficients (451, 452, 453). The [Sigma][Delta] modulator further comprises a tunable delay element (455), a frequency adjuster (480) for adjusting the sampling frequency f s such that the normalized center frequency f0/fs is constant, and a delay adjuster (490) for adjusting the loop delay td implemented by the quantizer and the tunable delay element (455), such that the normalized loop delay td/Ts falls in a predetermined range [tmin,tmax], where Ts=1/fs.

The invention discloses a noise control method and device of a smoke exhaust ventilator, the smoke exhaust ventilator and a storage medium. The noise control method of the range hood comprises the following steps: determining a target noise value of the range hood; acquiring the current power and the current rotating speed of a motor of the range hood; determining the current noise value of the range hood and the current blockage degree of a flue of the range hood according to the current power and the current rotating speed; determining whether the operation state of the motor needs to be adjusted according to the target noise value and the current noise value; and when the operation state of the motor needs to be adjusted, the operation state of the motor is adjusted based on the current blockage degree and the target noise value. According to the technical scheme, the problem that the range hood cannot adjust the running state of the motor in time according to the flue blocking degree is solved, and the effects that the running state of the motor is adjusted in time under the condition that the flue blocking degree is large or small, and stronger suction force is provided as much as possible under the condition that constant noise is kept are achieved.

Devices and methods are described for providing continuous measurement of an analyte concentration. In some embodiments, the device has a sensing mechanism and a sensing membrane that includes at least one surface-active group-containing polymer and that is located over the sensing mechanism. The sensing membrane may have a bioprotective layer configured to substantially block the effect and/or influence of non-constant noise-causing species.

A shock absorption device for mechanical equipment comprises a workbench; a limiting fixing rack is fixedly installed on the upper surface of the workbench; a table top shock absorption device is installed below the workbench in an inlaid mode; a plurality of supporting arms are vertically installed below the table top shock absorption device; one end of each supporting arm is fixedly connected with the table top shock absorption device; the other end of each supporting arm is provided with a tyre shock absorption device, and the supporting arms are movably connected with the tyre shock absorption devices; and steering wheels are movably installed below the tyre shock absorption devices. The shock absorption device for the mechanical equipment has the beneficial effects that tyre shock absorption is conducted through the tyre shock absorption devices, noise generated by high-intensity operation is lowered, and harm of continuous noise to workers is reduced; and by adopting the table top shock absorption device for absorbing shock, the shock absorption strength of the shock absorption device for the mechanical equipment is improved, noise generated by the shock absorption device forthe mechanical equipment is reduced, and the machine service life is prolonged.

A digital filter design apparatus for noise suppression using spectral subtraction comprising a first spectral estimator (12) for determining a noisy speech power spectrum with high frequency resolution from a noisy speech signal block Density estimates. A second spectral estimator (24) determines a high frequency resolution background noise power spectral density estimate from the background noise signal block. An averaging unit (20, 26) forms a piecewise constant estimate of the power spectral density of the speech with noise and a piecewise constant estimate of the power spectral density of the background noise. These averaging units are controlled by means (14, 16, 18) to adapt the length of the individual segments to the shape of the high frequency resolution noisy speech power spectral density estimate and to adapt the two piecewise constant Estimates use the same segment. Means (28) determine a piecewise constant digital filter transfer function using spectral subtraction based on a piecewise constant estimate of the noisy speech power spectral density and a piecewise constant background noise power spectral density estimate.

The invention discloses a low-noise amplifying system with constant noise and a linear phase during programmable attenuation. A first bilateral switch, an attenuating and compensating module, a second bilateral switch and a low noise amplifier are connected in sequence between an input end and an output end of the system. The system also comprises an adaptive digital programmable attenuation control module, wherein the adaptive digital programmable attenuation control module is applied to digital programmed control of amplitude attenuation, and used for performing signal channel adaptive control according to digital attenuation at the same time in order that a programmable attenuator keeps a system noise level constant in the presence of attenuation and keeps low insertion loss of a signal channel in the absence of attenuation, and the influence of the insertion loss of a programmable attenuation radio-frequency electronic switch on a system noise coefficient is lowered; the attenuating and compensating module is used for attenuating a signal amplitude, and compensating for an electric length of a signal phase during signal attenuation through the radio-frequency electronic switch by calculation of a frequency wavelength in order to obtain the same phase difference under different attenuation situations and compensate for phase deviations caused by programmable attenuation; and the low noise amplifier is used for realizing low noise amplification of signals.