16294 results about "Phase difference" patented technology

An alignment system uses a self-referencing interferometer that produces two overlapping and relatively rotated images of an alignment markers. Detectors detect intensities in a pupil plane where Fourier transforms of the images are caused to interfere. The positional information is derived from the phase difference between diffraction orders of the two images which manifests as intensity variations in the interfered orders. Asymmetry can also be measured by measuring intensities at two positions either side of a diffraction order.

An ambulatory medical device including a plurality of electrodes configured to be disposed at spaced apart positions about a patient's body, an electrode signal acquisition circuit, and a monitoring circuit. The acquisition circuit has a plurality of inputs each electrically coupled to a respective electrode of the plurality of electrodes and is configured to sense a respective signal provided by a plurality of different pairings of the plurality of electrodes. The monitoring circuit is electrically coupled to an output of the acquisition circuit and is configured to analyze the respective signal provided by each of the plurality of different pairings and to instruct the acquisition circuit to select at least one of the plurality of different to pairings to monitor based on at least one of the quality of the respective signal, a phase difference between the respective signal and that of other pairings, a position of electrodes relative to the patient's body, and other criteria.

The invention provides a forward and reverse motor for improving forward and reverse efficiency, and a control method thereof. By adopting the forward and reverse motor having a first winding and a second winding and a third winding both having the phase differences differing for 90 degrees of that of the first winding, and a switching circuit, the switching circuit connects the first winding as the main winding and the second winding as the secondary winding to the working circuit of the motor, or connects the third winding as the main winding and the first winding as the secondary winding tothe working circuit of the motor, thereby ensuring that the parameters of the number of turns, wire diameters and resistances of the main winding and the secondary winding in each case can be separately designed when the motor rotates forwards or reversely to ensure high efficiency of the motor in both forward and reverse rotations, which solves the problem that the forward and reverse motor cannot reach high efficiency in forward and reverse directions in the related art.

A millimeter-wave transmitter-receiver uses an NRD guide as a fundamental configuration and includes a millimeter-wave signal oscillator, a pulse modulator, a circulator, an antenna and a mixer. In the millimeter-wave transmitter-receiver, a line length of a third dielectric guide is set so that δ=±π in which δ is a phase difference at a center frequency between a portion of a transmission millimeter-wave signal, which is reflected via a third dielectric guide on the leading end portion of the third dielectric guide and returned to leak to a third connecting portion of the circulator, and another portion of the millimeter-wave signal, which leaks from a first connecting portion to the third connecting portion of the circulator. It is possible to reduce the change in the mixer output and enhance the millimeter-wave transmission/reception performance.

This invention is related to the calibration apparatus and method for compensating the phase characteristics in the receiving and transmitting signal paths of array antenna system, especially adaptive array antenna system operating as the base station system. The objective of this invention is to provide the calibration apparatus and method for the array antenna system to be able to compensate its phase differences or irregularities without any restrictions on the array structure or position of additional antenna or antenna toplogies while the array antenna system is in its operational mode such that the signals used by the subscribers are received or transmitted together with the signals used for the calibration. In this invention the phase delay between the additional antenna element and each of the antenna elements of the array antenna system is measured in advance of the calibration procedure to be used when the phase differences or irregularities are measured during the calibration procedure. The test signals used for the calibration is distinguishable from the signals used by the subscribers. Furthermore, each of the transmitting calibration signals itself is distinguishable from one another when the plural transmitting signal paths are to be calibrated simultaneously.

Embodiments of the present invention are directed at gathering position information of mobile and stationary entities and using the position information in a wide variety of applications. Various embodiments use a plurality of signal transmitting devices and/or a plurality of signal gathering devices to gather position information. In one embodiment, the signal transmitting device is an existing mobile electronic device. In another embodiment, the signal transmitting device is a radio frequency identification (RFID) tag attached to an entity. In another embodiment, the signal gathering device is a collection of wall mounted antennas. The entity location is calculated by gathering the phase difference or other timing information of signal generated by the signal transmitting device on the entity. This location information is then given to end user applications. One embodiment is a network security application using gathered location information of wireless ethernet cards. Another embodiment is a network resource locator application.

A retardation film that has an optical retardation layer whose alignment direction is controlled precisely and that is produced at a low cost, and also a method for producing the same, are provided. The explanation below relates to FIG. 1. First, a base-attached anisotropic layer 12 is prepared by laminating an optically anisotropic layer 11 on a transparent base 10. Next, on the optically anisotropic layer 11, a solution containing a polymer reacting with polarized ultraviolet light and a liquid crystalline compound is coated and dried. Then, it is irradiated with polarized ultraviolet light so as to align the liquid crystalline compound, and irradiated further with unpolarized ultraviolet light as required to crosslink the liquid crystalline compound, thereby forming a retardation film 1 having an optical retardation layer 13 that is directly formed on the optically anisotropic layer 11.

Communication is performed for a first communication device having a set of antenna elements. A quality-indication signal is received from a second communication device (e.g., a basestation). A complex weighting is calculated based on the quality-indication signal. A pre-transmission signal is modified based on the complex transmit diversity weighting to produce a set of modified-pre-transmission signals, wherein the modifications are symmetric by making approximately half the magnitude of the transmit diversity modification to one signal in a first direction, and approximately half the magnitude of the transmit diversity modification to the other signal in a second direction, opposite the first direction. Each modified pre-transmission signal from the set of modified-pre-transmission signals is uniquely associated with an antenna element from the set of antenna elements. The set of modified-pre-transmission signals is sent from the set of antenna elements to produce a transmitted signal.

Control means is provided, in which the whole of the phase difference of a power waveform of each phase is matched to a value dividing a cycle of the power waveform into n-equal portions, and at the same time, the whole of the power value of each phase is controlled to be identical, so that the power conversion unit having a n-alternating current output (n is an integer numeral serving as n≧2) connected to the direct current power source and smoothing means provided between the direct current power source and the power conversion unit are made small in capacity.

Plasma distribution is controlled in a plasma reactor by controlling the phase difference between opposing RF electrodes, in accordance with a desired or user-selected phase difference, by a phase-lock feedback control loop.

A method and system can locate an RF transponder based on phase differences between signals transmitted to the RF transponder. The method transmits from a first transponder to a second transponder first and second signals at first and second frequencies, respectively. The second signal is compared with the first signal and a distance between the first and second transponders is determined based on the phase difference between the first and second signals. In one embodiment, the first transponder is an interrogator, the second transponder is an RF tag, and the RF tag determines the phase difference between the two signals. In another embodiment, the first and second transponders are the interrogator and RF tag, respectively, but the interrogator determines the phase difference between the two signals after the two signal are reflected back to the interrogator. The method can also determine a position (distance and direction) of the RF tag by measuring the distances from two different locations of the interrogator to the RF tag. In one embodiment, the two distances are measured from two spaced-apart antennas of the interrogator. In another embodiment, the interrogator is moved from one known location to another known location. With distance measurements from both known locations, the location of the RF tag can be determined by simple geometry.

A circularly-polarized-wave patch antenna includes a main body having a patch electrode provided with two feeding points and a circuit for generating a phase difference of 90° between signals supplied to the feeding points. A Wilkinson distribution circuit is provided between the 90°-phase-difference generating circuit and a coaxial cable (feeder line) so as to improve a reflection characteristic. The patch antenna includes two feeding points, and thus a favorable axial ratio characteristic can be obtained in a wide band. Also, a favorable reflection characteristic can be obtained in a wide band because of the Wilkinson distribution circuit. Accordingly, the patch antenna can be used in a wider frequency band.

A rotary sensor that outputs two analog signals, such as one sine wave and one cosine wave and has multiple periods within one period of the electrical angle of a motor is employed. The motor is energized at each position for a specified length of time upon its startup by using multiple electrical angles corresponding to the multiple candidate absolute angles obtained from the rotary sensor signal as the initial position of the motor, and the electrical angle at which the motor acceleration becomes maximum is determined as the absolute angle. While the motor drive is in operation, on the other hand, the phase difference Δθ between the phase of the motor at the counter electromotive voltage and the control phase is directly computed from the parameters of the motor, sensed current, voltage command and angle speed so as to correct the shifted position. A high-efficiency motor drive unit with improved maintainability of rotary sensor and improved accuracy of sensing the magnet pole position of a permanent magnet synchronous motor that accelerates and decelerates very quickly in a wide range of speed is realized.

A circular-polarization dipole helical antenna is used for electronic device and satellite terminal and includes a base, and an antenna conductor arranged on surface of the base. The antenna conductor includes a plurality of metal conductors with high Q value and anti-oxidation property and continuously and helically coated on surface of the base. The base is made of low loss and high dielectric constant material. An unbalance-to-balance circuit module connects two signal-feeding ends to the base with phase difference of 180 degree. The problems of narrow bandwidth, low efficiency, complicated structure and precise manufacture can be solved.

A method and system for locating an RF transponder based on phase differences between signals received from the RF transponder. The method includes receiving a signal from the transponder and calculating distance, relative movement, and position by comparing I-Q phase angle vectors of the signals. Global scroll commands can be used following receipt of signals at first and second frequencies to quickly determine distance.

The invention comprises of methods and apparatus to estimate the position and velocity of a Mobile Receiver (MR) using either the Time Of Arrival (TOA) of signals received by the MR, their Phase Of Arrival (POA), their Strength Of Arrival (SOA), their Frequency Of Arrival (FOA), or a combination thereof, with respect to a reference produced by a Reference Receiver (RR) of known location. In order to solve for the coordinates of the MR, the invention uses either hyperbolic multilateration based on Time Difference Of Arrival (TDOA), or linear multiangulation based on Phase Difference Of Arrival (PDOA), or both. In order to solve for the velocity of the MR, the patent uses FOA based on Frequency Difference Of Arrival (FDOA). An important contribution of this invention is the way the MR receives, processes and combines available signals for location purposes. Another important contribution of this invention is the way the RR receives, processes and combines available signals for reference purposes. Yet another important contribution of the invention is the application of Super-Resolution (SR) techniques at both the MR and the RR to increase the resolution of the estimated TOAs, POAs, SOAs, or FOAs.

An integrated circuit layout includes dense figures and at least one isolated figure. A plurality of dummy patterns are formed to surround the isolated figure, so as to reduce the difference in pattern density of the integrated circuit layout. A transmitted light of the dummy patterns provides a phase difference of 0 or 180 degrees relative to a transmitted light of the integrated circuit layout. The integrated circuit layout and the plurality of dummy patterns are formed on a photo-mask.

There is provided a method comprising: determining a phase difference between at least two antenna units of a distributed antenna system on the basis of at least one pilot signal received from at least one of a plurality of antenna units; and transmitting phase correction commands to a common base station of the plurality of antenna units on the basis of the determined phase difference in order to synchronize carrier phases between at least two antenna units of the distributed antenna system.

The invention consists of methods and apparatus to estimate the position and velocity of a Mobile Receiver (MR) using either the Time Of Arrival (TOA) of signals received by the MR, their Phase Of Arrival (POA), their Strength Of Arrival (SOA), their Frequency Of Arrival (FOA), or a combination thereof, with respect to a reference produced by a Reference Receiver (RR) of known location. In order to solve for the coordinates of the MR, the invention uses either hyperbolic multilateration based on Time Difference Of Arrival (TDOA), or linear multiangulation based on Phase Difference Of Arrival (PDOA), or both. In order to solve for the velocity of the MR, the patent uses FOA based on Frequency Difference Of Arrival (FDOA). An important contribution of this invention is the way the MR receives, processes and combines available signals for location purposes. Another important contribution of this invention is the way the RR receives, processes and combines available signals for reference purposes.

A microwave oven includes a microwave generation device and a case. Three antennas are provided in the case. The two antennas are opposite each other along a horizontal direction. In the microwave generation device, a power distributor almost equally distributes a microwave generated by a microwave generator among phase variators. Each of the phase variators adjusts the phase of the fed microwave. This causes a phase difference between microwaves respectively radiated from the opposite two antennas to change. The microwaves are respectively radiated from the antennas.

A microscope is disclosed which determines a complex three-dimensional representation of an object based on a series of recordings of the light wave diffracted by the object, wherein the direction of the wave lighting of the object varies between two succesive recordings. The diffracted wave interferes with a reference wave on a receiving surface and a frequency representation of the diffracted wave is computed from interference patterns received on the receiving surface. A plurality of frequency representations of diffracted waves are then superimposed yielding a frequency representation of the object. The phase of each frequency representation of a diffracted wave is shifted in order to compensate for variations of the phase difference between the reference wave and the wave lighting of the object.