250results about How to "Improve noise characteristics" patented technology

We describe the use of a flow directing apparatus for incorporation into a patient mask or adjacent to it and for use with a source of pressurized breathable gas such as electronically or electronically controlled fan blower or positive displacement ventilator to provide nasal or oro-nasally administered continuous positive airway pressure or bi level therapies. Such therapies are commonly used to treat sleep disordered breathing including sleep apnea and other syndromes, as well as ventilatory insufficiency. The valve apparatus includes means to direct expired air to atmosphere and inspired air from a pressure source to a user's airway. In this way advantage is provided compared to alternative means as described in the prior art which vent a user's expired gas to atmosphere through a fixed open vent.

A hand held appliance, such as a hairdryer, includes a body having a fluid inlet for admitting fluid into the appliance, a fluid outlet, a duct lined with a material, and a primary fluid flow path extending from the fluid inlet to the fluid outlet and through the duct. The material may be a foam or a felt and is a sound absorbing material, a vibration absorbing material, is an insulator, is tuned to resonant frequencies of the appliance. The primary fluid flow path may be non-linear. The duct may have a non-circular cross-section and may comprise a handle portion of the appliance, and the handle portion of the duct is lined with said material. A fan unit may be provided located upstream of the handle portion. The duct may comprise a first handle portion and a second handle portion of the appliance.

In a high-pass (mirrored) integrator structure that employs chopper modulation, the input and output of the mirrored integrator are connected to the input and output ports of the operational amplifier, bypassing the chopper stabilization modulators. The mirrored integrator can be used in sigma-delta analog-to-digital converters.

A frequency comb laser providing large comb spacing is disclosed. At least one embodiment includes a mode locked waveguide laser system. The mode locked waveguide laser includes a laser cavity having a waveguide, and a dispersion control unit (DCU) in the cavity. The DCU imparts an angular dispersion, group-velocity dispersion (GVD) and a spatial chirp to a beam propagating in the cavity. The DCU is capable of producing net GVD in a range from a positive value to a negative value. In some embodiments a tunable fiber frequency comb system configured as an optical frequency synthesizer is provided. In at least one embodiment a low phase noise micro-wave source may be implemented with a fiber comb laser having a comb spacing greater than about 1 GHz. The laser system is suitable for mass-producible fiber comb sources with large comb spacing and low noise. Applications include high-resolution spectroscopy.

A wireless communication system includes: a filter; and a semiconductor chip including a signal processing integrated circuit having an amplifier, wherein a main surface of the semiconductor chip is provided with a plurality of electrode terminals along an edge portion thereof; wherein the amplifier has a transistor including a control electrode, a first electrode through which a signal is outputted, and a second electrode to which a voltage is applied; wherein the control electrode, the first electrode and the second electrode of the transistor are connected to the electrode terminals, respectively; and wherein none of wirings are arranged between the electrode terminals and placements of the control electrode, the first electrode and the second electrode, making space between the electrodes and the electrode terminals narrow.

A work to be coated with multi layers of coating films, is provided with a first layer of coating film formed by coating a powder coating material of a thermosetting resin containing an electroconductive filler and an elastomer on a surface to be coated on the work; and a second layer of coating film formed by coating a powder coating material of a thermosetting resin containing water repellent particles on the first layer of coating film. The first layer of coating film and the second layer of coating film are baked by heating. It is preferable that the work is a friction member including a metal pressure plate and a friction material.

A method for forming a laminated shield to improve the stability and performance of an MR read head and the MR read head formed using that shield. The shield consists of two layers of ferromagnetic material separated by a layer of ruthenium, allowing the ferromagnetic layers to form an antiferromagnetic configuration by means of a quantum mechanical exchange interaction. The antiferromagnetic configuration has a stable domain structure and a magnetization that forms closed loops around the shield edges thereby reducing noise in the readback signal and reducing disturbances to the magnetic state of the sensor element.

Integrated circuit output buffers include primary and secondary pull-down transistors and an output signal line electrically coupled to a drain of the primary pull-down transistor and a drain of the secondary pull-down transistor. A preferred control circuit is also provided. The control circuit turns on the primary pull-down transistor during first and second consecutive portions of a pull-down time interval and uses a signal fed back from the output signal line to control the timing of when a gate of the secondary pull-down transistor is electrically connected to a drain of the secondary pull-down transistor during the first portion of the pull-down time interval and also control the timing of when the gate electrode of the secondary pull-down transistor is electrically connected to a source of the secondary pull-down transistor during the second portion of the pull-down time interval. A pull-down portion of the control circuit may include a gate pull-up transistor having a drain electrically connected to the drain of the secondary pull-down transistor and a source electrically connected to a gate of the secondary pull-down transistor, and a gate pull-down transistor having a drain electrically connected to the gate of the secondary pull-down transistor and a source electrically connected to a source of the secondary pull-down transistor. These gate pull-up and pull-down transistors can be utilized to selectively turn on the secondary pull-down transistor during a first leading portion of a pull-down time interval and then turn off the secondary pull-down transistor during a second trailing portion of the pull-down time interval.

A cone-beam scanning system scans along a half circle. The reconstruction uses a weighting function which decreases for rows farther from the scan plane to take the redundancy of the projection data into account. Another embodiment uses a circle plus sparse helical scan geometry. Image data can be taken in real time.

A transconductor for receiving a differential voltage signal and outputting a differential current signal, includes two transconductors for receiving the differential voltage signal and outputting a single-end current signal. An inversion input terminal of one of the two transconductors is connected with a non-inversion input terminal of the other. The transconductor outputs a current signal output from each of the two transconductors as the differential current signal.

The invention discloses an ultra narrow linewidth low noise high power single frequency fiber laser which comprises a single mode semiconductor laser pumped source, a polarization-maintaining wavelength division multiplexing device, a coupling output polarization maintaining fiber raster, a high reflection polarization maintaining fiber raster, a wave plate, a high gain fiber, a low reflection narrow linewidth fiber grating, a dichroscope, a heat sink, a sealed air chamber and a fiber clamp and polarization maintaining fiber isolator. A common end of the polarization-maintaining wavelength division multiplexing device connects with the coupling output polarization maintaining fiber raster. The coupling output polarization maintaining fiber raster and the high reflection polarization maintaining fiber raster are etched on a same polarization maintaining fiber or respectively etched on two strips of polarization maintaining fibers with consistent fast and slow shaft directions in connection, the high reflection polarization maintaining fiber raster connects with the high gain fiber through the wave plate, the high gain fiber connects with the low reflection narrow linewidth fiber grating, and the dichroscope in order. According to the invention, a folding composite chamber and a double virtual annular chamber are constructed in a short straight chamber structure, and a single frequency fiber laser with ultra narrow linewidth and polarization-maintaining output is generated.

Disclosed are multiphase oscillators comprising a plurality of delay stages serially coupled in a loop by a plurality of nodes, with the loop being folded to provide two concentric rings of delay stages with equal numbers of allocated nodes. A second plurality of negative-resistance elements are provided, each element having a first output coupled to a node on the first concentric ring and a second output coupled to a node on the second concentric ring. Each such output switches between first and second voltage levels, and provides a negative resistance to a signal coupled to it during at least a portion of the transition between voltage levels. The outputs of an element switch to opposite voltage levels. With this construction, a high-voltage pulse propagates around the loop of delay stages, with a low-voltage pulse propagating behind it. Also disclosed are circuits to control the direction of pulse propagation.

A perpendicular magnetic recording medium includes a non-magnetic substrate, and at least a soft magnetic under layer formed of a soft magnetic material, an alignment-regulating layer for regulating the crystal alignment of a layer provided directly thereon, a perpendicular magnetic layer in which easy-magnetization axes are oriented generally perpendicular to the substrate, and a protective layer, the layers and the layer being provided atop the substrate, wherein the soft magnetic under layer exhibits magnetic isotropy or has easy-magnetization axes oriented perpendicular to the substrate. According to the present invention, an undercoat layer having no magnetic domain walls can be formed. When the undercoat layer is employed, there can be provided a perpendicular magnetic recording medium and a perpendicular magnetic recording and reproducing apparatus which exhibit high thermal stability and excellent noise characteristics, and which attain high-density recording.

A test device for measuring a phase noise of a test signal includes a delayer configured to delay the test signal to provide a delayed test signal, a first combiner, a second combiner, and a phase noise determinator. The first combiner is configured to combine a first signal with the delayed test signal to provide a first combiner output signal. The first signal is based on the test signal or a signal identical to the test signal. The second combiner is configured to combine a second signal with the delayed test signal, wherein the second signal is phase-shifted with respect to the first signal to provide a second combiner output signal. The second signal is based on the test signal. The phase noise determinator is configured to provide phase noise information that depends on the first combiner output signal and the second combiner output signal.

A solid state imaging device includes a transfer transistor for transferring signal charges generated by photoelectric conversion to a floating diffusion layer, a reset transistor for resetting a potential of the floating diffusion layer, and an amplifying transistor for outputting a signal corresponding to the potential of the floating diffusion layer. A low concentration impurity region having an impurity concentration lower than that of the first conductivity type semiconductor region is formed in part of a surface portion of the first conductivity type semiconductor region which is located below a gate electrode of the amplifying transistor and serves as a well region of the amplifying transistor.

A hand held appliance, such as a hairdryer, includes a body having a fluid inlet for admitting fluid into the appliance, a fluid outlet, a duct lined with a material, and a primary fluid flow path extending from the fluid inlet to the fluid outlet and through the duct. The material may be a foam or a felt and is a sound absorbing material, a vibration absorbing material, is an insulator, is tuned to resonant frequencies of the appliance. The primary fluid flow path may be non-linear. The duct may have a non-circular cross-section and may comprise a handle portion of the appliance, and the handle portion of the duct is lined with said material. A fan unit may be provided located upstream of the handle portion. The duct may comprise a first handle portion and a second handle portion of the appliance.

The invention provides a phase locked loop having a modulator which is based on a ΣΔ fractional N phase locked loop. In the forward path of the PLL, the output of the oscillator has an additional frequency divider which provides the output frequency of the PLL in a plurality of different phases. A multiplexer which is connected upstream of the multimodulus divider in the PLL's feedback path and which is actuated by the ΣΔ modulator, like the divider, selects the respective desired phase. This allows the minimum step size of the division factors to be reduced to values of less than 1 relative to the output frequency, which significantly reduces the quantization noise. The PLL bandwidth may therefore advantageously be the same size as the modulation bandwidth.

An optical waveguide device comprises a substrate having first and second surfaces, and an optical waveguide provided on the first surface of the substrate, having a light-incoming facet and a facet inclined with respect to the optical waveguide. Guided light incident to the optical waveguide through the light-incoming facet is totally reflected off the inclined facet, and the guided light is transmitted through the first or second surface of the substrate.

The invention provides a high-speed semiconductor device structure and a forming method thereof. The structure comprises a substrate, a Ge-containing strained layer formed on the substrate, an Si cap layer formed on the Ge-containing strained layer, a T-shaped gate structure formed on a part of the Si cap layer and covering the groove, and a source electrode and a drain electrode formed on the two sides of the T-shaped gate structure, wherein the Ge-containing strained layer has a groove. In the positive channel metal oxide semiconductor (PMOS) device structure of the embodiment of the invention, the two strained SiGe layers or Si layers with low Ge content on and below the strained SiGe layer or the strained Ge layer with high Ge content are arranged, so that a hole potential well can be formed in the strained SiGe layer or the strained Ge layer with high Ge content, the migration rate of the current carrier is increased and the performance of the semiconductor device is greatly improved.

A multi-element airfoil system includes an airfoil element having a leading edge region and a skin element coupled to the airfoil element. A slat deployment system is coupled to the slat and the skin element, and is capable of deploying and retracting the slat and the skin element. The skin element substantially fills the lateral gap formed between the slat and the airfoil element when the slat is deployed. The system further includes an uncoupling device and a sensor to remove the skin element from the gap based on a critical angle-of-attack of the airfoil element. The system can alternatively comprise a trailing edge flap, where a skin element substantially fills the lateral gap between the flap and the trailing edge region of the airfoil element. In each case, the skin element fills a gap between the airfoil element and the deployed flap or slat to reduce airframe noise.

Disclosed herein is an apparatus for driving a touch panel, which calibrates a drift of an output voltage, generated by a change of an external environment or touch panel, thereby having excellent noise characteristics, high touch sensitivity. The apparatus includes a touch panel having a plurality of pixels. Each of the pixels is connected to a first capacitor in which their electric charges are stored. A differential amplifier receives and amplifies the amount of electric charges generated by a change in the capacitance of the first capacitor of the touch panel, inputted through two input terminals and outputs the amplified voltage to two output terminals. An analog to digital converter (ADC) receives an output of the differential amplifier as an input and converts the output into a digital value. A reference voltage calibrator outputs positive and negative voltages to the differential amplifier and calibrates a reference voltage. An error calibrator outputs positive and negative voltages to the differential amplifier and calibrates two outputs of the differential amplifier within a voltage input range of the ADC. A controller feeds back the two outputs of the differential amplifier, which are beyond the voltage input range of the ADC, to the error calibrator.

A wireless communication system includes: a filter; and a semiconductor chip including a signal processing integrated circuit having an amplifier, wherein a main surface of the semiconductor chip is provided with a plurality of electrode terminals along an edge portion thereof; wherein the amplifier has a transistor including a control electrode, a first electrode through which a signal is outputted, and a second electrode to which a voltage is applied; wherein the control electrode, the first electrode and the second electrode of the transistor are connected to the electrode terminals, respectively; and wherein none of wirings are arranged between the electrode terminals and placements of the control electrode, the first electrode and the second electrode, making space between the electrodes and the electrode terminals narrow.

An apparatus and method for frequency synthesis using a Delay Locked Loop (DLL) are provided. The apparatus includes the DLL, an edge pulse generator, and an inductive-capacitive (LC) tank switch. If phases of a reference frequency signal and a feedback signal are the same and thus are locked, the DLL delays the reference frequency signal. The edge pulse generator generates a plurality of pulse signals representing phase delay amounts of signals. The LC tank switch combines the plurality of pulse signals and generates frequency.

An optical signal receiving circuit has a current-voltage converting circuit which receives the output current signal of a photoelectric converting circuit, converting an optical signal into the current signal, and converts the current signal into a voltage signal. A differential circuit in the subsequent stage to the current-voltage converting circuit uses a resistor as its current source to facilitate setting of an operating voltage level in the circuit. To eliminate an adverse effect of asymmetry of the output waveform from the differential circuit due to the use of the resistor, the reference voltage level as the other input to the reference circuit is generated from the output voltage signal of the current-voltage converting circuit by a voltage generating circuit incorporating a feed-forward-controlling connection. Thus, coexistence of high bandwidth characteristics and broad dynamic range having so far been difficult to attain by low voltage apparatus can be realized.

In a magnetoresistive effect transducer including a pinning layer, a pinned layer, a free layer and a non-magnetic layer inserted between the pinned layer and the free layer, a longitudinal bias layer is connected directly to a part of the free layer to apply a bias magnetic field to the free layer, thus biasing a magnetization direction of the free layer so that the magnetization direction of the free layer coincides with that of the longitudinal bias layer.

An all-digital phase locked loop (ADPLL) generates a feedback word representing a continuous-time oscillating signal. The ADPLL includes a time-to-digital converter (TDC) configured to be input with the continuous-time oscillating signal and a reference signal. The reference signal is a function of a reference clock signal. The TDC is configured to generate a digital word, the feedback word being a function of the digital word. The ADPLL includes a delay circuit configured to be input with at least one of the reference clock signal and the continuous-time oscillating signal and to be controlled by a first dither signal.

An RF signal generator divides an input radio signal into an amplitude signal and a phase signal and outputs the amplitude signal and the phase signal. A switching amplifier amplifies the radio signal with the amplitude signal and the phase signal. The switching amplifier includes at least one variable current sources that is controlled by the amplitude signal and supplies a current to the switching amplifier. The switching amplifier includes at least one switching elements that connects the variable current sources to one of a terminal connected a ground potential and an output terminal of the switching amplifier according to the phase signal.

Disclosed is a complex elliptic filter having an order of three or higher which receives two differential signals that differ in phase from each other by 90 degrees are applied and outputs two differential signals that differ in phase from each other by 90 degrees. The complex filter circuit has internally at least two circuit blocks that include a capacitor connected in series with a coupler (gyrator). The complex filter is a third-order inverse Chebychev filter having an equiripple stopband of 40-dB attenuation amount. Alternatively, the coupler (gyrator) between elliptic capacitors is removed. Alternatively, the elliptic capacitors are made substantially equal to the capacitor arranged in parallel therewith. Alternatively, the gm value of an OTA and the capacitance value are each in an integral ratio represented substantially by a geometric progression of 2.

There is provided an optical amplifier including a Raman amplification medium, a rare earth doped fiber located at a latter stage of the Raman amplification medium, a first pump light outputting unit for outputting pump light with a plurality of wavelengths, a variable distribution element for distributing the pump light with the plurality of wavelengths, outputted from the first pump light outputting unit, to the Raman amplification medium and the rare earth doped fiber in a variable distribution ratio for each wavelength, and a control unit for individually controlling the distribution ratio of the pump light with the plurality of wavelengths in the variable distribution element and the power of the pump light with the plurality of wavelengths from the first pump light outputting unit in accordance with a wavelength arrangement of each of signal lights wavelength-multiplexed into the wavelength-multiplexed signal light.