q

Equipment for type setting




q

Apparatus and method of compensating for I/Q imbalance in direct up-conversion system

An apparatus and a method of compensating for an I/Q imbalance in a direct up-conversion system prevents the performance of the system from being deteriorated by efficiently compensating for an I/Q timing skew, an I/Q phase imbalance, and an I/Q gain imbalance by using a characteristic of an OFDM scheme in an Orthogonal Frequency Domain Multiple (Access) (OFDM(A)) system using a direct up-conversion scheme. According to the apparatus and the method of compensating for an I/Q imbalance in the direct up-conversion system of the present invention, an OFDM(A) system using a direct up-conversion scheme may efficiently compensate for I/Q timing skew, I/Q phase imbalance, and I/Q gain imbalance by using a characteristic of an OFDMA scheme, so that a performance of the system is prevented from being deteriorated.




q

Carrier frequency offset compensation apparatus and associated method

A carrier frequency offset compensation method for a communication system is provided. The method includes: mixing, filtering and interpolating an input signal according to a mixing parameter, a first filtering parameter and a first interpolation parameter, respectively, to generate a processed result; calculating a carrier frequency offset estimation value of the input signal according to the processed result; adjusting the mixing parameter according to the carrier frequency offset estimation value; and mixing, filtering and interpolating the input signal according to the adjusted mixing parameter, a second filtering parameter and a second interpolation parameter, respectively. The first interpolation parameter is associated with a cut-off frequency corresponding to the first filtering parameter.




q

Radio frequency (RF) receivers with whitened digital clocks and related methods

Radio frequency (RF) receivers having whitened digital clocks and related methods are disclosed. Disclosed embodiments generate whitened clocks having random variations that are used to operate digital processing blocks so that interference created by the whitened clocks is seen as white noise within the received RF signal spectrum. RF input signals are received by RF front-ends (RFFEs) that output analog signals associated with channels within the RF input signals. These analog signals are converted to digital information and processed by digital receive path circuitry that outputs digital data associated with the channel. The digital receive path circuitry includes a whitened clock generator that generates a whitened clock having random variations and which a digital processing block that operates based upon the whitened clock. Further, the RFFE and the digital receive path circuitry are located within a single integrated circuit.




q

Very low intermediate frequency (VLIF) receiver and method of controlling a VLIF receiver

A very-low intermediate frequency (VLIF) receiver and a method of controlling a VLIF receiver. The method comprises receiving a first signal, the first signal including one or both of an on-channel signal portion and an adjacent channel interferer (ACI) portion; determining that the first signal includes a portion having a strength that is above a threshold; in response to determining that the first signal includes a portion having a strength that is above the threshold, estimating one or more IQ imbalance parameters for at least a portion of the first signal; and compensating for an IQ imbalance in at least the portion of the first signal using the one or more IQ imbalance parameters.




q

Wideband multi-channel receiver with fixed-frequency notch filter for interference rejection

A wideband multi-channel receiver comprises an antenna configured to receive a radio frequency band. A band-pass filter is in signal communication with the antenna, and a low-noise amplifier is in signal communication with the band-pass filter. A mixer is in signal communication with the low-noise amplifier and is configured to translate a radio frequency band to an intermediate frequency (IF) band. A tunable local oscillator is in signal communication with the mixer. At least one fixed-frequency notch filter is in signal communication with the mixer, with the notch filter configured to reject at least one interference signal in the IF band while passing remaining signals in the IF band. An analog-to-digital converter is in signal communication with the notch filter and is configured to convert the remaining signals in the IF band to digital signals.




q

Data transmission apparatus having frequency synthesizer with integer division factor, corresponding method, and data transmission system

A data transmission apparatus disposed within two network layers operative at different data rates is provided. The data transmission apparatus is coupled to a clock generator which provides a reference clock for a lower network layer and is coupled to a frequency synthesizer with an integer division factor that generates a divided clock for an upper network layer according to the reference clock and the integer division factor. The data transmission apparatus includes a first processing circuit and a second processing circuit. The first processing circuit corresponding to the upper network layer receives and transmits data by using the divided clock as its operation frequency. The second processing circuit corresponding to the lower network layer receives and transmits data from the first processing circuit by using the reference clock as an operation frequency for encoding data. The divided clock is generated from the frequency synthesizer with the integer division factor.




q

System and method for blind frequency recovery

Described herein are systems and methods for accurately estimating and removing a carrier frequency offset. One exemplary embodiment relates to a system comprising a frequency offset detection circuit detecting a carrier frequency offset in an optical signal, and a frequency testing circuit calculating an estimated frequency offset value of the carrier frequency offset, wherein the frequency testing circuit removes a carrier phase based on the estimated frequency offset value and recovers the optical signal. Another exemplary embodiment relates to a method comprising detecting a carrier frequency offset in an optical signal, calculating an estimated frequency offset value of the carrier frequency offset, removing a carrier phase based on the estimated frequency offset value, and recovering the optical signal.




q

Techniques for navigation among multiple images

Aspects of the disclosure relate generally to providing a user with an image navigation experience. In order to do so, a reference image may be identified. A set of potential target images for the reference image may also be identified. A drag vector for user input relative to the reference image is determined. For particular image of the set of target images an associated cost is determined based at least in part on a cost function and the drag vector. A target image is selected based on the determined associated costs.




q

Method for driving liquid crystal display device

In a first subframe period, light sources of a first region and a third region emit lights at the same time; light sources of a second region and a fourth region emit no light at the same time, in which light emission of different colors is performed in the first region and the third region. In a second subframe period, light sources of the second region and the fourth region emit lights at the same time; light sources of the first region and the third region emit no light at the same time, in which light emission of different colors is performed in the second region and the fourth region. The first region and the third region are separated from each other with the second region interposed therebetween; and the second region and the fourth region are separated from each other with the third region interposed therebetween.




q

Liquid crystal pixel correction using pixel boundary detection

A video processing circuit detects a risk boundary that is a part of a boundary between a dark pixel and a bright pixel, and is determined in accordance with the tilt azimuth of liquid crystal molecules from a boundary changed over the previous frame to the current frame and, for at least one side of dark pixels and bright pixels brought into contact with the detected risk boundary, corrects a video signal designating the application voltage of a liquid crystal element corresponding to the pixel of the frame brought into contact with the risk boundary out of a plurality of frames from the current frame to k frames (here, k is a natural number) following the current frame such that a lateral direction electric field generated between the dark pixel and the bright pixel decreases.




q

Liquid crystal display device

A liquid crystal display device comprising a backlight and a pixel portion including first to 2n-th scan lines, wherein, in a first case of expressing a color image, first pixels controlled by the first to n-th scan lines are configured to express a first image using at least one of first to third hues supplied in a first rotating order, and second pixels controlled by the (n+1)-th to 2n-th scan lines are configured to express a second image using at least one of the first to third hues supplied in a second rotating order, wherein, in a second case of expressing a monochrome image, the first and second pixels controlled by the first to 2n-th scan lines are configured to express the monochrome image by external light reflected by the reflective pixel electrode, and wherein the first rotating order is different from the second rotating order.




q

High frequency switch

There is provided a high frequency switch having a reduced circuit scale while maintaining satisfactory harmonic characteristics in a transfer path of a high frequency signal. The high frequency switch includes: at least one transmission port; at least one reception port; a common port; transmission side series switches each including a body contact type FET; transmission side shunt switches each including a body contact type FET; reception side series switches each including a body contact type FET; and reception side shunt switches each including at least one floating body type FET.




q

Frequency-tunable filter

A frequency tunable filter is disclosed. The frequency tunable filter includes a filter unit that can tune a frequency band of a frequency signal being filtered, a communication module that receives a control signal for controlling the tuning of the frequency band, and a control unit that controls the tuning of the frequency band based on the control signals. The disclosed filter can control the tuning of the filter's frequency band wirelessly.




q

Quarter wave plate polarizer with two phase-shifting portions

A right circular cylindrical body of an isotropic dielectric such as a cross-linked styrene copolymer, has respective pluralities of mutually parallel grooves formed in its axial end faces, spaced apart by an intermediate portion whose dimension c is a half wavelength. The axial lengths a, b of the grooves are such that when a wave passes through the body, a quarter wavelength phase difference is produced between a component of a wave having its E-vector parallel to the grooves and a component of the wave having its E-vector orthogonal to the grooves. Alternatively the plate may consist of two or more discrete bodies whose grooves are dimensioned to produce a total differential phase shift of one quarter wavelength.




q

Attenuation reduction control structure for high-frequency signal transmission lines of flexible circuit board

An attenuation reduction control structure for high-frequency signal transmission lines of a flexible circuit board includes an impedance control layer formed on a surface of a substrate. The impedance control layer includes an attenuation reduction pattern that is arranged in an extension direction of the high-frequency signal transmission lines of the substrate and corresponds to bottom angle structures of the high-frequency signal transmission lines in order to improve attenuation of a high-frequency signal transmitted through the high-frequency signal transmission lines. An opposite surface of the substrate includes a conductive shielding layer formed thereon. The conductive shielding layer is formed with an attenuation reduction pattern corresponding to top angle structures of the high-frequency signal transmission lines.




q

High frequency electronic component

An electronic component includes: a first circuit connected to a first common terminal for inputting/outputting a first signal set, a second common terminal for inputting/outputting a second signal set having a frequency higher than the first signal set, and a third common terminal for being connected to an antenna; and a second circuit connected in parallel to the first circuit between the first and second common terminals, wherein the first circuit includes a first filter transmitting the first signal set and reflecting the second signal set, and a second filter transmitting the second signal set and reflecting the first signal set, the third common terminal is located between the first and second filters, and the second circuit reflects a first transmission signal and a second transmission signal, transmits parts of the first and second transmission signals, and inverts phases of the parts of the first and second transmission signals.




q

Minimal intrusion very low insertion loss technique to insert a device to a semi-rigid coaxial transmission line

A signal conditioning apparatus can include a coaxial cable having at least one slot formed therein. A conductive film can be applied to the coaxial cable so as to cover each slot. A device mounting surface can be formed within the slot and a protection device can be mounted on the device mounting surface. A housing consisting of one or more interlockable portions can be coupled to the coaxial cable.




q

Electronic dobby-and-jacquard-loom weaving machine and weaving method

The present invention discloses an electronic-dobby-and-jacquard-loom weaving machine and a weaving method. The machine comprises a weaving body, a first warp beam, a second warp beam, a jacquard loom, a dobby loom, a harness frame, a plurality of first harness wires, a plurality of second harness wires, a plurality of harness cords, a plurality of return springs and at least one weft accumulator, wherein the weaving body and the jacquard loom are connected with a synchronous transmission mechanism between them; the synchronous transmission mechanism comprises a weaving spindle, a main motor encoder, a jacquard loom transmission shaft, a jacquard loom encoder, a gear box and a servo control system. The present invention improves the clarity of the fell (shed), widens the fell, keeps the fell clear stably, and realizes high-density jacquard weaving.




q

Liquid crystal display

In a liquid crystal display according to an exemplary embodiment of the present invention, a shielding electrode applied with the same voltage as a common voltage and overlapping a data line is not formed. Instead, an opening is formed at a position corresponding to a data line disposed proximate to a sub-pixel charged with a relatively low voltage. In this manner, luminance deterioration of a liquid crystal display may be reduced or prevented, and a short defect between the shielding electrode and the data line may also be prevented.




q

Method and device for primary frequency regulation based on bang-bang control

The present invention provides a method and a device for primary frequency regulation based on bang-bang control, the method comprises: obtaining in real-time a power grid frequency of a steam turbine generator set; performing a subtraction operation on a rated power grid frequency and said power grid frequency to generate a power grid frequency difference; performing a dead zone process on the power grid frequency difference according to a dead zone fixed value to generate a frequency difference; performing a frequency difference compensation operation on the frequency difference to generate a frequency difference compensation instruction; and combining an original primary frequency regulation output instruction with the frequency difference compensation instruction and outputting the result to a steam turbine speed regulation system when a selecting switch is 1.




q

Power supply device, power acquisition device and safety system for electromagnetic induction-powered electric vehicle

It is provided a power supply device and a power acquisition device for an electromagnetic induction-powered electric vehicle that increase a power transfer efficiency by maximizing a lateral deviation tolerance and by minimizing a gap between the power acquisition device and the power supply device while preventing the power acquisition device from colliding with an obstacle present on a road and being damaged by the collision.




q

Ultra slim power supply device and power acquisition device for electric vehicle

An ultra slim power supply device for supplying power to an electric vehicle in a contactless manner includes at least one power supply track buried in a road. Each power supply track includes a plate-shaped magnetic core extending along the road, a plate or strip shaped magnetic field generator arranged above the magnetic core through which an alternating current is supplied to generate a magnetic field, a plate or strip shaped insulating body positioned between the magnetic core and the magnetic field generator to isolate them from each other, and a housing for enclosing the magnetic core, the magnetic field generator and the insulating body.




q

Aerial cable car system having transportation operating equipment for passenger and/or freight transport

An aerial cable car system including transportation operating equipment for passenger and/or freight transport, wherein electrical consumers are connected for operation thereof to a rechargeable electrical energy store of a transportation operating equipment by a respective power circuit. The transportation operating equipment includes an operating control device connected to measuring devices for dynamically capturing measurement values based on available quantity of energy in the energy store. The operating control device includes a storage module having at least one stored measurement control value and an associated control parameter. The operating control device includes a filter module comparing a captured measurement value to the at least one stored measurement control value and reading out corresponding stored control parameter, based on which power circuits can be selectively coupled or decoupled to the energy store by the operating control device. Electrical consumers in transportation operating equipment can be fed without interruption by the energy store, even during travel.




q

Transport vehicle equipped with current collector

A transport vehicle equipped with a current collector, includes: a vessel to load a load; a current collector that extends to receive electric power from an overhead line and contracts and retracts so as to be disposed away from the overhead line; and a vehicle body that rotationally drives driving wheels by at least one of the electric power from the current collector and a self-propelled driving source and on which the vessel is placed; a pantograph position detector that detects a relative position of the current collector and the overhead line; and a control device that controls a driving direction of the vehicle body or gives an instruction of information with which a direction in which the vehicle body is to be operated can be recognized, so that the relative position is brought to a position where the current collector and the overhead line are connected.




q

Heater for liquefied petroleum gas storage tank

A catalytic tank heater includes a catalytic heating element supported on an LPG tank by a support structure that holds the element in a position facing the tank. Vapor from the tank is provided as fuel to the heating element, and is regulated to increase heat output as tank pressure drops. The heating element is internally separated into a pilot heater and a main heater, with respective separate fuel inlets. The pilot heater remains in continual operation, but the main heater is operated only while tank pressure is below a threshold. Operation of the pilot heater keeps a portion of the catalyst hot, so that, when tank pressure drops below the threshold, and fuel is supplied to the main heater, catalytic combustion quickly expands from the area surrounding the pilot heater to the remainder of the catalyst.




q

Equine training device

An ergonomically designed timing module is integrated with an equine training whip, normally carried by the equestrian, especially for those needing to improve riding skills in point-to-point timed events such as cross country, stadium jumping, racing, barrel racing. This combination provides for safe operation and convenient viewing while in the saddle.




q

Lead equipped with means for blocking the extensible cord

An extensible cord lead comprising a casing (11) containing a winding wheel (13) equipped with housings (15) intercepted by a pushbutton (16) to allow the partial or total blocking of the cord, the pushbutton (16) being equipped with a forward position blocking device consisting of a cursor (20) which slides or rotates in a transverse direction with respect to the axis of the pushbutton (16) in which it is inserted, said cursor (20) being activated by a thumb-turn (21) located on the head of the pushbutton (16), said cursor (20) being able to move from a blocked position to free sliding of the pushbutton, entering and exiting transversally to the sliding axis of the pushbutton (16), in a housing (22) in the box-like casing (11) of the winding device.




q

Low torque and vacuum seed meter

A seed meter is provided for use with a row crop planter or seed planter that includes a seed disk assembly that rotates within a meter housing cavity and that has a seed disk assembly cavity in which a vacuum pressure is applied for pulling seeds into seed pockets of a seed disk of the seed disc assembly. The vacuum pressure is applied to the seed disk assembly by pulling a vacuum airflow through a spindle that supports the seed disk assembly. A wiper seal is arranged in a fixed position within the seed disk assembly cavity and seals against the seed disk assembly as a support plate and seed disk of the seed disk assembly rotate over the wiper seal, so that the wiper seal creates a boundary between a vacuum zone and a non-vacuum zone inside of the seed disc assembly cavity.




q

Electric arc for aqueous fluid treatment

An aqueous fluid treatment method and system is provided which preferably uses a 3 step electro-chemical oxidation process to remove organic contaminates from water. A high surface area electro-chemical reaction cell can be employed to remove organic particles and precipitate hardness salts from the aqueous solution. Several 3-phase spark arcs generated mixed oxidants and acoustic cavitations to remove dissolved organic compounds and oxidize organic metal compounds in the next step. Finally, a dielectric discharge in aqueous foam is used to eliminate recalcitrant organic compounds such as, but not limited to, polychlorinated aromatics, disinfectants, pesticides, and pharmaceuticals before release to environment or recycled.




q

Liquid sample measuring device

The present liquid sample measuring device comprises a device body on which a biosensor is detachably mounted, a liquid biological sample being dispensed in drops on the biosensor; a measuring section that measures bioinformation from the liquid biological sample; a motion measuring section that measures motion information of the device body; a motion assessment section that assesses the degree of motion of the device body on the basis of the motion information of the device body measured by the motion measuring section; and a measurement controller that adjusts the measurement time for measuring the bioinformation on the basis of the assessment result of the motion assessment section.




q

Metal material with a bismuth film attached and method for producing same, surface treatment liquid used in said method, and cationic electrodeposition coated metal material and method for producing same

A metal material is provided with a bismuth coating which enables the subsequent coating to be accomplished at a high throwing power, and has excellent corrosion resistance, coating adhesion and is able to be produced with reduced damage to the environment. The metal material has a surface and a bismuth-containing layer deposited on at least a part of the surface of the metal material, wherein the percentage of bismuth atoms in the number of atoms in the surface layer of the metal material with a bismuth coating is at least 10%.




q

Group III nitride based quantum well light emitting device structures with an indium containing capping structure

Group III nitride based light emitting devices and methods of fabricating Group III nitride based light emitting devices are provided. The emitting devices include an n-type Group III nitride layer, a Group III nitride based active region on the n-type Group III nitride layer and comprising at least one quantum well structure, a Group III nitride layer including indium on the active region, a p-type Group III nitride layer including aluminum on the Group III nitride layer including indium, a first contact on the n-type Group III nitride layer and a second contact on the p-type Group III nitride layer. The Group III nitride layer including indium may also include aluminum.




q

Convertible ski systems having toe binding mounts and associated quick-release locking mechanisms

A ski system includes a ski, a heel binding provided on an upper surface of the ski, a toe binding mount provided on the upper surface of the ski forward of the heel binding, a toe binding releasably mounted to the toe binding mount, and a quick-release locking mechanism for locking the toe binding to the toe binding mount. The quick-release locking mechanism is configured for release by hand.




q

Multiple axle equalizing rubber suspension

A suspension system for a vehicle includes a frame mounting bracket for mounting to the vehicle. The suspension includes front and rear rubber torsion axle assemblies. Front and rear lever assemblies are respectively pivotally attached to the vehicle at front and rear lever pivot points. Outer housings of the rubber torsion axle assemblies are each respectively rigidly mounted to the front and rear lever assemblies. A rigid control arm is pivotally connected at one end to the front lever assembly at a front control arm pivot point and its other end is pivotally connected to the rear lever assembly at a rear control arm pivot point. When the suspension assembly encounters a force causing the front lever assembly to rotate in one direction about the front lever pivot point the rigid control arm causes the rear lever assembly to rotate about the rear lever pivot in an opposite direction.




q

Method and apparatus for opening threaded joints of drilling equipment

The invention relates to a method and apparatus for opening threaded joints of drilling equipment (6) by striking the drilling equipment (6) with the percussion device of a rock drilling rig (1) and by measuring vibration originating from the drilling equipment (6) during striking. In addition to vibration, measuring means (9) measure a parameter defining at least one additional condition, on the basis of which the decision to stop striking is made.




q

Wear indicators for drilling equipment

Described herein is a wear indicator (100) for use in a drill bit or a core head. The wear indicator (100) comprises an elongate element that forms part of the drill bit. The elongate element has a plurality of numbers (110, 120, 130, 140, 150, 160, 170, 180) formed along its length, each number (110, 120, 130, 140, 150, 160, 170, 180) being formed as a void and corresponds to a level of wear in accordance with the IADC dull grading system. As the drill becomes worn, the wear indicator (100) wears at the same rate to reveal one of the numbers (110, 120, 130, 140, 150, 160, 170, 180). The numbers range from “1” to “8” where the number “1” illustrates the least wear and the number “8” indicates the most wear. When unworn, none of the numbers are visible.




q

THz frequency range antenna

A THz frequency range antenna is provided which comprises: a semiconductor film (3) having a surface adapted to exhibit surface plasmons in the THz frequency range. The surface of the semiconductor film (3) is structured with an antenna structure (4) arranged to support localized surface plasmon resonances in the THz frequency range.




q

Identifying the presence of an individual near medical radiation emitting equipment

Systems and methods are disclosed herein to a radiation safety system comprising radiation emitting medical equipment; a radiation safety system controller connected to the radiation emitting medical equipment through a first communication means configured to determine a number of people within a radiation room housing the radiation emitting medical equipment and prevent the radiation emitting medical equipment from performing radiation emitting functions if the radiation safety system controller determines that more people than a maximum allowed number of people are presently in the radiation room; and a scanner connected to the radiation safety controller through a second communication means configured to detect people in the radiation room and communicate to the radiation safety system controller that a person has been detected.




q

Multi-sector computed tomography image acquisition

An approach is disclosed for acquiring multi-sector computed tomography scan data. The approach includes activating an X-ray source during heartbeats of a patient to acquire projection data over a limited angular range for each heartbeat. The projection data acquired over the different is combined. An image having good temporal resolution is reconstructed using the combined projection data.




q

Acquisition method and apparatus for mass spectrometer data

A method and apparatus for acquiring data from a mass spectrometer and its transmission to a computer system including a data acquisition engine, a network interface and a throughput optimization module which includes a ring buffer and a protocol stack. A compression engine may be provided between the acquisition engine and the ring buffer. The ring buffer is configured as a number of segments containing portions of memory matching the size of data words from the acquisition engine. When a segment is full of data corresponding to the words, or is partially full and has received data containing an end of scan marker, the number of words in the segment is written into a header word in the segment and the data in that segment are moved to the protocol stack. Subsequent data is received by the next segment in the buffer.




q

Quantum dot photo-field-effect transistor

Photo-field-effect transistor devices and associated methods are disclosed in which a photogate, consisting of a quantum dot sensitizing layer, transfers photoelectrons to a semiconductor channel across a charge-separating (type-II) heterointerface, producing a sustained primary and secondary flow of carriers between source and drain electrodes. The light-absorbing photogate thus modulates the flow of current along the channel, forming a photo-field effect transistor.




q

Separate connection device for grounding electrical equipment comprising a plurality of separate electrical components

A separate connection device (40) intended to be inserted between a metal frame (3), of an electrical component (1), and a metal supporting structure (20) in order to connect, electrically and separately, the frame to the supporting structure. The connection device (40) comprises a metal blade manufactured from spring steel which comprises two self-connecting end areas (45, 46) arranged in separate planes and comprising a set of sharp teeth (47) arranged in order to be embedded within the metal material and formed on a folded section of the metal blade so that the sets of teeth (37, 47) extend in opposite directions and in planes intended to intersect the planes of the frame (3) and of the supporting structure (20) when the connection device is mounted.




q

Surface treatment equipment including a laser engraving system for treatment of a strip

A surface treatment equipment is designed for forming nickel barriers on a plurality of terminals for preventing solder wicking is disclosed. The surface treatment equipment includes a retractable feeding system, a laser engraving system, an image sensor, and a control system. The retractable feeding system is utilized to transmit a strip that has the terminals. The laser engraving system is utilized to ablate the terminals. The image sensor is utilized to collect a plurality of images of the ablated terminals. The control system receives the images to perform image recognition. When a defective terminal is recognized, the control system controls the retractable feeding system to transmit in reverse and controls the laser engraving system to repeatedly ablate the defective terminal. The defective terminals can be automatically recognized by the image sensor accompanying the control system. Thus, the drawback of a human visual inspection is solved.




q

Stock feeder for woodworking equipment

A stock feeder for woodworking equipment includes a base, a cross clamp, a horizontal bar unit, a vertical bar unit, a feeding unit, and an electrical unit. The electrical unit has an electrical unit main body and a variable-frequency drive. The electrical unit main body has a first housing, a plurality of heat dissipation grooves provided on the outer periphery of the first housing, and a power fan which is independently mounted on a top portion of the first housing and in communication with the heat dissipation grooves. The variable-frequency drive has a second housing, a variable-frequency circuit sealed in the second housing, and a control panel exposed outside the second housing. The second housing has an outer surface provided with a plurality of heat dissipation slots corresponding in position to and in communication with the heat dissipation grooves of the electrical unit main body.




q

Variable frequency ratiometric multiphase pulse width modulation generation

Groups of phase shifted Pulse Width Modulation signals are generated that maintain their duty-cycle and phase relationships as a function of the period of the PWM signal frequency. The multiphase PWM signals are generated in a ratio-metric fashion so as to greatly simplify and reduce the computational workload for a processor used in a PWM system. The groups of phase shifted PWM signals may also be synchronized with and automatically scaled to match external synchronization signals.




q

Low-loss, broad band, LC I/Q phase shifter

Some embodiments relate to a phase shifter that includes an I/Q phase shifter and at least one LC balun. Compared to conventional phase shifters, phase shifter has primarily only LC components, thereby limiting losses relative to conventional solutions. In one embodiment, for example, a phase shifter shows a large bandwidth at 77 GHz center frequency (e.g., 1 dB amplitude error bandwidth is approximately 40 GHz; 1° phase error bandwidth is about 16.5 GHz). The inductors included in phase shifter, in contrast to the quarter wave transmission lines used in conventional phase shifters, reduces chip area compared with conventional solutions. In some embodiments, an emitter follower helps to provide a relatively constant output that is largely independent of temperature, input power, VCC, manufacturing variation, and so on.




q

Systems and methods for frequency synthesis to improve coexistence

A frequency synthesizer for a WLAN transceiver is disclosed that may be used to generate 5.4 GHz and 2.4 GHz signals. The frequency synthesizer may be configured to minimize VCO pulling by using VCO operating frequencies that are not integer multiples of the RF bands. Further, the frequency synthesizer may be configured to minimize interference with other frequency bands used by existing wireless systems.




q

Glitch-free frequency modulation synthesis of sounds

A time-varying formant is generated at a formant frequency by generating first and second harmonic phase signals having first and second harmonic numbers, respectively, in relation to a modulation frequency. The first and second harmonic phase signals are generated in proportion to a master phase signal, which varies at the modulation frequency, modulo a factor corresponding to their harmonic numbers. First and second sound signals, based on the first and second harmonic phase signals, are frequency modulated to create an arbitrarily rich harmonic spectrum, depending on an FM index. The time-varying formant is generated by generating a time-varying combination of the first and second harmonic sound signals, weighting the first and second harmonic sound signals in accordance with their spectral proximities to the formant frequency. One or more of the harmonic numbers are updated when the time-varying formant frequency passes the frequency of either sound signal.




q

Sequence generation and transmission method based on time and frequency domain transmission unit

A method for generating/transmitting a transmission-unit symbol sequence is disclosed. In the case of transmission information, the information is modulated in time and frequency domains on the basis of a predetermined transmission unit (e.g., a transmission time interval TTI or slot), simultaneous transmission of the information is made, and then a transmission unit symbol is generated/transmitted. A transmission sequence is masked in each symbol contained in one transmission unit. Symbol-unit circular shift (cyclic shift) is applied to the masked result, so that transmission efficiency increases. A control signal transmission method for supporting a variety of formats and a signal transmission method based on a prime-length sequence are also provided.