863results about How to "Improve frequency characteristics" patented technology

Provided are a magnetic sheet for use in a radio frequency identification (RFID) antenna, an RFID antenna including the magnetic sheet, and a method of manufacturing the magnetic sheet, in which the magnetic sheet includes an amorphous alloy selected from the group consisting of Fe—Si—B, Fe—Si—B—Cu—Nb, Fe—Zr—B and Co—Fe—Si—B. The magnetic sheet is made by laminating amorphous alloy ribbons made of an amorphous alloy between magnetic sheet layers formed of alloy powder including at least one amorphous alloy and then compression-molding the amorphous alloy ribbons, to thereby control microcrack of the amorphous alloy ribbons and enhance characteristic of an end-product. The magnetic sheet is also thin, and has an excellent magnetic permeability, and a simple manufacturing process.

The present invention provides a microphone device with good frequency characteristics. The microphone device can pick up sound faithfully. In detail there is provided a microphone device comprising a microphone element, a signal processor, and a cover disposed over the microphone element and the signal processor, the cover including a mesh structure occupying 25% or more of at least one surface of the cover.

Intelligent alarm clock arrangement adapted into an electric device and utilizing the microphone, loudspeaker or other alarming device, memory unit, processor and timer feature thereof. The apparatus is located near a sleeping subject so as to sample and analyze the statistical properties of sound signals produced by the movements of the sleeping subject and to classify the sleep states according to the analyzed signals into a peaceful calm deep sleep, a light sleep with arousals and awake periods associated with the movements. An alarm wakes up the subject during a pre-programmed time window, if there are arousals, awake state and movements present at that time to induce the awakening at a biologically advantageous instant. Instead of the local alarm function, the device may perform a remote alarm using a call or sending a message to a pre-programmed phone number when the awakening of the sleeping subject is detected.

A boundary acoustic wave device using SH boundary acoustic waves includes a first medium layer, a second medium layer stacked on the first medium layer, and an electrode including an interdigital electrode and reflectors. A sound absorbing layer is provided on the surface of the first medium layer and/or the second medium layer opposite the interface therebetween.

The transmission delay time of a receiver for receiving a differential signal is reduced. A first amplifier circuit is provided in an input stage of the receiver, and a second amplifier circuit is provided in an output stage of the receiver. The first amplifier circuit is a differential input, differential output amplifier circuit. The second amplifier circuit is a differential input, single-ended output amplifier circuit. A first power supply voltage and a second power supply voltage are input as a high-level power supply voltage and a low-level power supply voltage to the first amplifier circuit and the second amplifier circuit, respectively. The withstand voltage of transistors of a differential pair of the first amplifier circuit is higher than the withstand voltage of another transistor included in the first amplifier circuit and a transistor included in the second amplifier circuit.

A piezoelectric panel speaker improved in frequency characteristics has a panel and a piezoelectric exciter for vibrating the panel. The exciter includes a casing and a piezoelectric exciter element accommodated in the casing. The casing has an outer surface with a part positioned proximate to and facing one side surface of the panel. The side surface of the panel has an area opposed to the part of the outer surface of the exciter. A securing layer is partially formed between the area of the panel and the part of the outer surface to secure the exciter to the panel. The securing layer is made of a material so that vibration is transmittable from the exciter to the panel.

A drive mechanism @is comprised with a set comprising a plurality of magnetic bodies, means for supplying a frequency signal to said set, and means for producing movement caused by the attraction/repulsion between the magnetic bodies. The movement is the driving source of the drive mechanism.

Microphone array for achieving a substantially frequency-independent directivity using a plurality of microphones disposed along a rectilinear array. The rectilinear array is at least as long as the wavelength of the lowest frequency, where a useful directivity is desired. The rectilinear array has a first end and a second end. The microphones close to the first end are intended for the highest frequencies and the microphones close to the second end are intended for the lowest frequencies. The mutual spacing of the microphones is frequency-dependent. The signals from the individual microphones are band-pass filtered, the passbands and cut-off frequencies of the individual band-pass filters being adapted to the frequency band the individual microphones are intended for. The individual band-pass filters are adapted such that the amplitude of the summated signal after band-pass filtering is substantially the same when a sinus-shaped test signal is used, the amplitude of said test signal being constant and the frequency of said test signal varying within the frequency range where the microphone array is to have a substantially frequency-independent directivity.

A coil package which makes it easy to handle a high-frequency cone/pyramid-shaped coil and enhance frequency characteristics without degrading the characteristics of the coil. The cone/pyramid-shaped coil has a conical or pyramidal shape formed by wiring a conductor wire around an outer peripheral surface of a core such that the winding diameter of the coil progressively decreases from one end to the other end of the coil. The coil and a dielectric substrate are integrated with each other by forming a hole for inserting a tip portion of the coil in the dielectric substrate, making the bottom of the hole and a back surface of the dielectric substrate electrically continuous by a via, placing the coil in the hole by directing a small-diameter side of the cone/pyramid-shaped coil to the hole, electrically connecting the bottom of the hole and a tip-side lead wire extending from the coil to each other, and connecting an electrode on a large-diameter side of the coil to an electrode on the dielectric substrate.

To provide a semiconductor device with small parasitic capacitance. Alternatively, to provide a semiconductor device with low power consumption. The semiconductor device includes a transistor and a capacitor. The transistor includes a first conductor, a first insulator over the first conductor, a semiconductor including a region overlapping with the first conductor with the first insulator interposed therebetween, a second insulator over the semiconductor, a second conductor including a region overlapping with the semiconductor with the second insulator interposed therebetween, and a third conductor and a fourth conductor including a region in contact with a top surface of the semiconductor. The capacitor includes a layer formed from the same layer as the first conductor and a layer formed from the same layer as the third conductor and the fourth conductor.

A switching power amplifier having a pulse width modulation (PWM) signal generation unit that converts an input audio signal into a PWM signal with a predetermined carrier frequency, a correction unit that corrects the difference between an audio signal included in the PWM signal and a negative feedback output audio signal to generate a corrected PWM signal, a low pass filter that removes a high-frequency component from the corrected PWM signal, a frequency modulation unit that modulates the corrected PWM signal so that the corrected PWM signal has a switching frequency different from the carrier frequency of the input PWM signal to generate a modulated PWM signal, and a power amplification unit that amplifies a power of the modulated PWM signal.

An electromagnetic electroacoustic transducer, includes: a diaphragm; a magnet; an electromagnetic coil; and a casing for storing the diaphragm, the magnet and the electromagnetic coil therein. The case has at least one first sound emitting hole through which a front space on a front surface of the diaphragm in the casing communicates with a front outer space in front of the casing and at least one second sound emitting hole through which a rear space on a rear surface of the diaphragm in the casing communicates with the front outer space in front of the casing. A resonant frequency Fv2 of the rear space is set at a value in the range: F0<Fv2≦Fv1 in which F0 is a resonant frequency of the diaphragm, and Fv1 is a resonant frequency of the front space.

A voltage-controlled oscillating circuit according to the present invention includes: a drive voltage generating circuit outputting a bias voltage according to a control voltage; and a ring oscillator circuit receiving supply of the bias voltage to operate. The drive voltage generating circuit generates the bias voltage using a feedback circuit formed by an operational amplifier receiving supply of a power source voltage to operate. Therefore, an influence of a high frequency component overlapped on the power source voltage, that is an influence of noise, is suppressed, thereby enabling stable generation of an output clock having a small variation in phase.

The invention relates to a nickel-zinc ferrite material for wireless signal sensing, a sheet core and a preparation method thereof. The nickel-zinc ferrite material comprises main components which are calculated by the following oxides in mole percent: 48.0-62.5mol% of Fe2O3, 15.3-25.5mol% of NiO, 18.5-23.5mol% of ZnO and 3-10mol% of CuO; and the nickel-zinc ferrite material additionally comprises auxiliary components which are calculated by the following standard substances in weight percent relative to the total weight of the main components: 0.05-0.10wt% of nano CaCO3, 0.30-0.85wt% of nano SiO2, 1.50-2.50wt% of Mn3O4, 0.05-0.35wt% of Co2O3 and 1.00-1.50wt% of Bi2O3. The nickel-zinc ferrite material is prepared by adopting an oxidation method. The sheet core is a reticular sheet, the length is 45-250mm, the width is 45-250mm, the thickness is 0.05-0.3mm, the sheet core is formed by small sheets in a connecting way, the gaps among the small sheets are less than 50mum, and the sheet core is directly molded and then is sintered, or a magnetic bar is molded and then is sliced into small sheets which form the sheet core through an SMT (surface mount device) technology. At frequency of 13.56MHz, the material has the electromagnetic performance that mu' is equal to 125 plus or minus 20% and the mu'' is less than or equal to 4. Therefore, the material can satisfy the requirement of high-frequency low consumption on the ferrite material for wireless signal sensing.

This invention puts forward a MESFFT structure used in HF and large power field, namely, a biconcave structure of MESFET, in which, two independent grooves are formed on the active layer between a gate source and a drain by etching and a projected platform is formed between the two grooves, the gate electrode can deposit on the platform totally or the groove between the platform and the gate source to form a step structure, and the groove between the gate source and the drain stops the exhaust layer under the gate electrode to expand to the source and drain shift region so as to reduce the source and drain capacitance to increase the frequency property of the devices, and the groove can reduce thickness of channels of the shift region and modulate the field distribution of the shift region.

A semiconductor photodetector device includes: a first semiconductor layer of a first conductivity type; and a second semiconductor layer of a second conductivity type formed on the first semiconductor layer and having a light-receiving region. The first semiconductor layer includes a first region containing an impurity of the first conductivity type at a high concentration and a second region formed on the first region and containing an impurity of the first conductivity type at a concentration lower than that of the first region. The second semiconductor layer includes a third region containing an impurity of the second conductivity type at a concentration higher than that of the second region and a fourth region formed on the third region and containing an impurity of the second conductivity type at a concentration higher than that of the third region.

To provide a communication apparatus and a SAW device wherein the steepness in the vicinity of the outside of the lower frequencies of a passband can be improved. On a piezoelectric board 100, a SAW element 11 is formed which has first to fifth IDT electrodes 1-5 and reflector electrodes 6,7 with first to fourth electrode-finger narrow-pitch portions N1-N4 being formed in the respective ones of adjoining portions of the respective first to fifth IDT electrodes 1-5. An unbalanced signal terminal 8 and balanced signal terminals 9,10 are connected to the SAW element 11. The electrode finger pitches of the first to fourth electrode-finger narrow-pitch portions N1-N4 are formed symmetrically with respect to the third central IDT electrode 3 in such a manner that the electrode finger pitch of the first electrode-finger narrow-pitch portion N1 is narrower than that of the second electrode-finger narrow-pitch portion N2, while the electrode finger pitch of the fourth electrode-finger narrow-pitch portion N4 is narrower than that of the third electrode-finger narrow-pitch portion N3.

The purpose of the present invention is to provide an alcoholic solvent, in which FeCo based particles becoming a soft magnetic material are improved, for enhancing properties of a magnetic material using no heavy rare earth elements, and is to provide a sintered magnet produced by using it.

An alcoholic solution comprising FeCo-based particles and rare earth fluoride mixed together,

• • wherein particle diameters of said FeCo-based particles are larger than particle diameters of said rare earth fluoride particles,
  • particle diameters of said FeCo-based particles are from 20 to 200 nm, and
  • particle diameters of said rare earth fluoride particles are from 1 to 50 nm.