329 results about "Power modulation" patented technology

A laser processing system for micromachining a workpiece includes a laser source to generate laser pulses for processing a feature in a workpiece, a galvanometer-driven (galvo) subsystem to impart a first relative movement of a laser beam spot position along a processing trajectory with respect to the surface of the workpiece, and an acousto-optic deflector (AOD) subsystem to effectively widen a laser beam spot along a direction perpendicular to the processing trajectory. The AOD subsystem may include a combination of AODs and electro-optic deflectors. The AOD subsystem may vary an intensity profile of laser pulses as a function of deflection position along a dither direction to selectively shape the feature in the dither direction. The shaping may be used to intersect features on the workpiece. The AOD subsystem may also provide rastering, galvo error position correction, power modulation, and/or through-the-lens viewing of and alignment to the workpiece.

A power control structure aims for an electric power tool which gets an input power from an electric power source and converts the input power to a driving power to drive an electric motor. The electric power tool further includes a manual control means, a magnetic control element and a power modulation circuit. The manual control means includes a trigger portion movable by depressing of a user and a magnetic element movable with the trigger portion. The magnetic control element outputs an output control signal in proportion to alterations of a magnetic field caused by movements of the magnetic element. The power modulation circuit gets the input power and modulates to the driving power controlled by the output control signal to drive the electric motor. Thus by depressing the trigger portion, output power of the electric motor can be controlled to provide precise control of rotational speed and torque alterations.

An ultra low power, low complexity, low collision, deterministic modulation method that also works as a massive medium access mechanism for communication systems is based on positioning data in a communication resource space, such as time and frequency, such that the position of a symbol in that space determines its value and its access to the medium. The number base of the symbol is determined by the size of the subset of the resource space it is positioning itself in and, thereby, a few sparsely located symbols can convey a large value, while the remainder of the space can be simultaneously and massively used by other sparsely resource using members of the network.

The invention discloses a frequency modulation characteristic control policy for a doubly-fed wind turbine generator-energy storage system by simulating a synchronous machine. The control policy is characterized by comprising the steps of establishing the doubly-fed wind turbine generator-energy storage system considering self wind power frequency modulation capacity; enabling the doubly-fed wind turbine generator-energy storage system to simulate capacity configuration of the frequency modulation characteristic of the synchronous machine, and enabling the doubly-fed wind turbine generator-energy storage system to perform frequency modulation control policy analysis and the like; establishing the doubly-fed wind turbine generator-energy storage system by analysis of the frequency modulation requirement of the system, combination of the self frequency modulation capacity of the doubly-fed wind turbine generator, and reasonable configuration of the energy storage capacity; reasonably allocating the power modulation capacity according to different frequency response time of the wind turbine generator and the energy storage system to endow the doubly-fed wind turbine generator-energy storage system with frequency response capability which is similar to that of a conventional synchronous generator so as to realize bidirectional frequency modulation; and by fully utilizing the complementary advantages of the wind turbine generator and the energy storage system under different air speeds in the aspects of frequency response speed, available frequency modulation energy and the like, lowering the energy storage configuration cost. The control policy has the advantages of scientific and reasonable property, high applicability, excellent effect and the like.

At a time point T₀ when starting a process, a duty ratio of a high frequency power RF1 to which power modulation is performed is set to be an initial value (about 90%) which allows plasma to be ignited securely under any power modulating conditions. At the substantially same time of starting the process, the duty ratio of the high frequency power RF1 is gradually reduced from the initial value (about 90%) in a regular negative gradient or in a ramp waveform. At a time point t₂ after a lapse of a preset time T_d, the duty ratio has an originally set value D_s for an etching process. After the time point t₂, the duty ratio is fixed or maintained at the set value D_s until the end (time point T₄) of the process.

An alternator system (50, 52) that, in one aspect, utilizes a Lundell style alternator that is augmented by power electronic switching components (62) in the output section. In one embodiment, some of these power switching embodiments employ a scaling of stator turns and wire size to achieve the superior performance at higher speeds. The alternator system provides significantly enhanced power capability above idle as compared with classical Lundell alternator systems using Lundell alternators of the same size that are designed with the same power capability at idle. In one preferred dual voltage embodiment, a power switch (semi-conductor) connects the alternator output directly to the low voltage load at low engine speeds and when the power switch is "opened" at higher speeds, the alternator's power is channeled to the higher voltage. In a 14-volt/42-volt dual-voltage system, this arrangement provides triple the alternator's power capability at high speeds as compared to a conventional unenhanced capabilities of the altenator system of the present invention are accomplished without increasing the alternator size or required current capacity and without using high frequency semiconductor power modulation (106).

A method for driving AC of light emitting diodes includes an AC obtaining measure for obtaining an AC sine wave signal having positive and negative half-cycle waveforms; a power modulation measure for modulating the AC sine wave signal and an impedance of first and second LED groups according to at least two opposite conducting directions connected in parallel to change the positive half-cycle waveform to comply with an operation range of the positive half-cycle driving signal of the first LED group and modulate the negative half-cycle waveform to comply with an operation range of the negative half-cycle driving signal of the second LED group; and a power driving measure for driving the first and second LED groups by the positive and negative half-cycle driving signals, and the first and second LED groups are driven sequentially according to the operating cycles of the positive and negative half-cycle driving signals respectively.

A processing method for depositing porous silica and doped silica films is provided. The method uses a cyclic scheme wherein each cycle comprises first codepositing silica with silicon, then selectively removing the silicon to form a porous structure. In a preferred embodiment, the codeposition is carried out by plasma enhanced chemical vapor deposition. The reagent feed stream comprises a mixture of codeposition reagents and a selective silicon removal reagent. RF power modulation is used to control the codeposition and the selective silicon removal steps with the later proceeds whenever the RF power is turned off or reduced to a low level. A porous film with highly uniform small pores and a desired porosity profile can be obtained with this method. This method is advantageous for forming a broad range of low-k dielectrics for semiconductor integrated circuit fabrication. The method is also advantageous for forming other porous films for other applications.

A cellular communication system and method is described where a low-cost repeater is used to reduce the transmit power of a cell phone. The cell phone transmits a low-power modulated carrier signal to a nearby repeater. The repeater amplifies the signal and transmits it to a cellular base-station. The reduction of cell phone transmit power lowers the exposure of humans to RF radiation and increases the battery life of the cell phone.

A radio base station node (20) of a telecommunications network comprises a baseband transmitter (22) and plural radio frequency (RF) paths (24) between the baseband transmitter (22) and an antenna system (30). A measurement entity (32) is provided, preferably near the antenna system (30), for making a measurement or comparison of a time of detecting of a power modulation for each of plural RF transmission paths (24), e.g., a time of detecting of a power modulation for a first of the plural RF transmission paths and a time of detection of a power modulation for a second of the plural RF transmission paths. A transmission timing adjustment unit (34) uses the power modulation measurement or comparison for adjusting timing of transmission of signals for the plural RF transmission paths for obtaining a desired time alignment for the plural RF transmission paths.

An envelope tracking power transmitter includes an envelope amplifier, a common-gate power modulation linearizer and a power amplifier. The envelope amplifier may receive a first envelope voltage to generate a power supply voltage that is amplified in proportion to change of the first envelope voltage. The common-gate power modulation linearizer may receive a second envelope voltage to amplify the second envelope voltage according to change of the second envelop voltage. The power amplifier may receive a first output of the envelope amplifier as a power supply voltage and a drain bias voltage, may receive a second output of the common-gate power modulation linearizer as a common gate bias voltage, and may amplify a radio frequency (RF) input signal to provide a RF output signal by maintaining an output capacitance according to an envelope of the RF input signal.

A compact transformer coupled modulator is described. The modulator includes a transformer comprising a primary and a plurality of secondary windings, where each secondary winding has an output terminal. The modulator also includes a plurality of switches, where each switch is associated with a respective secondary winding and has input and output terminals and a control terminal. The control terminal of each switch is in electrical communication with a respective output terminal of the plurality of secondary windings. Each of the plurality of switches is substantially simultaneously switched by an input signal applied to the primary.

A power adapter apparatus and a power management method thereof are disclosed in the invention. The power adapter includes an output interface and a power modulation unit. The power adapter can be electrically connected with an electronic device through the output interface. There is a detective structure disposed on the output interface. The power management method includes steps of: 1) detecting whether the power adapter apparatus is electrically connected with the electronic device by the detective structure; and 2) when the output interface is detected to be disconnected from the electronic device, switching the power modulation unit to a standby state, so as to reduce a total power consumption of the power modulation unit.

A method and system for producing a film (preferably a thin film with highly uniform or highly accurate custom graded thickness) on a flat or graded substrate (such as concave or convex optics), by sweeping the substrate across a vapor deposition source operated with time-varying flux distribution. In preferred embodiments, the source is operated with time-varying power applied thereto during each sweep of the substrate to achieve the time-varying flux distribution as a function of time. A user selects a source flux modulation recipe for achieving a predetermined desired thickness profile of the deposited film. The method relies on precise modulation of the deposition flux to which a substrate is exposed to provide a desired coating thickness distribution.

Crosstalk between tracks, land prepit leakage, and effects of recording power modulation can cause the wobble signal period to change irregularly, thereby producing jitter in the recording clock which is derived by frequency multiplying the wobble signal. This problem is resolved by a recording clock generating circuit having an arrangement to average the wobble signal period, a timer for generating a rectangular wave with substantially the same period as the average period, and a frequency multiplying PLL for multiplying the timer output. The period averaging arrangement in particular determines the approximate average period at every wobble period and reflects the phase difference between the wobble signal and the timer in the timer setting so as to improve recording clock stability.

A system includes an uninterruptible power supply and a grid-tie inverter, connected to batteries via double conversion of high quality DC power sources. A Grid Interactive Double Conversion unit includes DC source with MPPT control and power modulation; a Bi-directional DC battery port; a Bi-direction AC grid port; a Pure Sine wave AC output; a Generator AC input, and DC contacts to prevent the inverter from back feeding generator during a power failure.

An electrosurgical ablation device provides pulse width modulated DC power to a heating segment in a catheter for use in providing treatment. In some embodiments the DC power to be modulated is sourced from an AC/DC power converter coupled to a source of AC power. In some embodiments the DC power to be modulated is sourced from a battery. In some embodiments the device switchably selects for modulation DC power sourced from either the AC/DC power converter or the battery, for example based on availability of power from the AC/DC power converter.

A data recording method according to the present invention is a method for recording data as edge position information, including marks and spaces of multiple different lengths, on a storage medium by irradiating the storage medium with a pulsed energy beam. The method includes the steps of: (A) generating a NRZI data based on the data to be recorded; (B) determining a write pulse waveform, defining the power modulation of the energy beam, according to the code lengths of respective codes included in the NRZI data; and (C) modulating the power of the energy beam based on the write pulse waveform. If the shortest code length of the NRZI data is n (which is an integer equal to or greater than one), a write pulse waveform that has only one write pulse is assigned to recording mark making periods corresponding to codes with code lengths x of n, n+1 and n+2, and a write pulse waveform that has multiple write pulses Pw is assigned to recording mark making periods corresponding to codes with code lengths x of n+3 or more.