56results about How to "Suppress low frequency noise" patented technology

The invention relates to a self-biased phase-locked loop which comprises a phase frequency detector, a charge pump, a loop filter, a voltage controlled oscillator, a frequency demultiplier and a biased current converter, wherein charging or discharging current output by the charge pump is equal to a first control current; a resistor of the loop filter is controlled by a first control voltage and a second control voltage, the second control voltage is adjusted according to the first control voltage and a second control current, and the loop filter increases or reduces the first control voltage according to the charging or discharging current output by the charge pump; the voltage controlled oscillator generates oscillating voltage and biased current according to the first control voltage, and accelerates or slowers oscillating frequency according to the increase or the reduction of the oscillating voltage; and the biased current converter converts the biased current to a first control current and the second control current, wherein the first control current is equal to the ratio of the biased current and a constant; and the second control current is equal to the ratio of the biased current and the frequency demultiplication number of the frequency demultiplier. The self-biased phase-locked loop has the characteristics of simple current and low dithering.

Provided is a friction material composition including: a binder; an organic filler; an inorganic filler; and a fiber substrate, in which a content of copper as an element is 0.5% by mass or less, the friction material composition contains at least one of phlogopite or biotite in a total of from 3% by mass to 9% by mass, and a graphite in an amount of from 2% by mass to 6% by mass, as the inorganic fillers, the at least one of phlogopite or biotite has an average particle size of from 340 μm to 1,500 μm, and the graphite has an average particle size of from 450 μm to 1,100 μm.

Provided is a gas turbine device that can effectively suppress low frequency noise and low frequency vibrations during low-load operation, without causing an increase in exhaust gas pressure loss. The gas turbine device is provided with the following: a gas turbine engine (GT) having an exhaust diffuser (20) that forms the upstream section of an exhaust gas flow path (30); exhaust struts (31) provided in the diffuser (20); and revolution suppression plates (32) that extend in the axial direction and are disposed on the downstream side of the exhaust struts (31) in the exhaust gas flow path (30).

The invention can effectively suppress noises such as high-frequency noise, low-frequency noise, baseline drift, power frequency interference and myoelectric interference of the pulse signal, and effectively improve the signal-to-noise ratio. The signal after the denoising of the present invention has no unnecessary oscillation, greatly improves the operation efficiency, saves a lot of resources, can be used for low power consumption front-end pulse signal acquisition, and provides a good solution for the further work of subsequent pulse wave feature extraction and classification Effect. The present invention can not only be used to remove the noise of the pulse signal, but also can be used to remove the noise of other signals such as the electrocardiogram signal.