|| List of recent Center Frequency-related patents
| Elastic wave filter device and duplexer|
An elastic wave filter device includes a one-port elastic wave resonator and an elastic wave filter unit connected in series to the one-port elastic wave resonator. The one-port elastic wave resonator is connected in parallel to an inductance.
Murata Manufacturing Co., Ltd.
| Semiconductor device and cascading matched frequency window tuned lc tank buffers|
A tunable buffer circuit has a first tunable buffer cell receiving an input signal. A first transmission line is coupled to the first tunable buffer cell.
|Quality factor estimation of a reverberant cavity|
A method comprises collecting a data set of field characterization measurements at a location inside a reverberant cavity excited by signals having multiple discrete electromagnetic frequencies; and performing a number (n) of circular shifts on the data set by a frequency step (Δf) and computing a covariance-based coefficient at each shift until the coefficient indicates a lack of correlation. The method further comprises computing a quality factor (q) of the reverberant cavity as fc/(Δf×n), where fc is center frequency of the data set..
The Boeing Company
Provided is an optical pulse-generator capable of efficiently using by a low driving voltage an entire band of an optical frequency comb input to a chirp compensator for the formation of an optical pulse. According to a graph shown in fig.
Sumitomo Osaka Cement Co., Ltd.
|Probe beam frequency stabilization in an atomic sensor system|
An atomic sensor system includes a magnetic field generator configured to generate a magnetic field along an axis and a probe laser configured to generate an optical probe beam. Beam optics direct the optical probe beam through a sensor cell comprising an alkali metal vapor such that the optical probe beam has at least a vector component along the axis.
Northrop Grumman Systems Corporation
|Calibration for a tunable rf filter structure|
Embodiments of radio frequency (rf) front-end circuitry are disclosed where the rf front-end circuitry includes a tunable rf filter structure and a calibration circuit. The tunable rf filter structure includes (at least) a pair of weakly coupled resonators and defines a transfer function with a passband.
Rf Micro Devices, Inc.
|System and short uhf antenna with floating transmission line|
A short, efficient antenna utilizing a floating coax transmission line over ground or overlapping wire feed structure for reduced antenna size for use in handheld radios. An asymmetric transmission line radiator having a length (ltl) is oriented substantially planar to and proximal to a truncated ground plane, and having at one end an input/output connector, and at an other end a feed point at least one of above a ground plane and proximal to its edge.
Motorola Solutions, Inc
|One way time of flight distance measurement|
Determination of distance and/or position relative to one or more points by transmission of a wideband signal by a first antenna, reception of the transmitted wideband signal by a second antenna and comparison of the time delay between the transmitted and received signals. The first and second antennas are connected to a timer/processor unit.
Tdc Acquisition Holdings, Inc.
|Plasma processing apparatus, abnormal oscillation determination method and high-frequency generator|
Disclosed is a plasma processing apparatus including: a processing container; a plasma generating mechanism including a high-frequency oscillator, and configured to generate plasma within the processing container by using a high frequency wave oscillated by the high-frequency oscillator; an impedance regulator configured to adjust impedance to be applied to the high-frequency oscillator; and a determining unit configured to change the impedance to be adjusted by the impedance regulator and to determine an abnormal oscillation of the high-frequency oscillator based on a component of a center frequency of a fundamental wave that is the high frequency wave oscillated by the high-frequency oscillator, and a component of a peripheral frequency present at both ends of a predetermined frequency band centered around the center frequency of the fundamental wave in a state where the impedance is changed.. .
Tokyo Electron Limited
|Characterizing a downstream path of a cable network|
Downstream channel parameters of a cable network are displayed in graphical form as a function of the channel number or center frequency. Such parameters, including digital channel demodulation parameters, may be plotted concurrently as frequency spectra, revealing frequency signatures of particular network impairments.
Jds Uniphase Corporation
Digital fiber link transporting multiple analog bands for agile conversion
A digital (fiber optic) link transports one or more rf digital signal blocks, that when converted into analog and (optionally) converted to a rf center frequency with an d-a converter, form rf analog signal blocks. The rf analog signal block occupies a specified frequency band and is preferably capable of being distributed over a downstream coaxial portion of a hfc network and/or being broadcast.
Cable Television Laboratories, Inc.
Filtering system, filtering method, tv signal receiver and tv signal receiving method
A filtering system includes a first filtering module, which includes a first frequency translating device and a first filter. The first frequency translating device includes a center frequency control end that receives a first control signal and an input end that receives an input signal, and performs a first frequency translation on the input signal by utilizing a first control frequency of the first control signal as a center frequency.
Mstar Semiconductor, Inc.
Methods and signal filtering
Systems and techniques for filtering of radiofrequency signals. A plurality of tunable cross-couple resonators are connected using capacitive coupling elements to form a cross-coupled bandpass filter.
Method for setting operating channel in white space band and device therefor
Disclosed are a method for setting an operating channel in a white space band and a device therefor. Particularly, a method for enabling a first device to set an operating channel in a white space band comprises the steps of: acquiring information on an available tv channel from a geo-location database; and setting an operating channel on the basis of the information on the available tv channel, wherein a center frequency of the operating channel can be set differently according to a tv channel used by an incumbent device among tv channels adjacent to the tv channel on which the operating channel is set..
Lg Electronics Inc.
Mixed resonator monolithic band-pass filter with enhanced rejection
A narrowband filter tuned at a center frequency. The filter comprises an input terminal, an output terminal, and a plurality of resonators coupled in cascade between the input terminal and the output terminal.
Reducing transmission signal artifact spacing
A method of generating a transmission signal may include mixing a baseband signal assigned for transmission within a narrow frequency range (“assigned narrow frequency range”) included in a wireless communication channel to produce a shifted signal. The shifted signal may have a shifted frequency that is based on a shift from the assigned narrow frequency range toward a center frequency of the wireless communication channel by a frequency offset.
Multi-band interference optimization
Rf communications circuitry, which includes a first rf filter structure and control circuitry, is disclosed. The first rf filter structure includes a pair of weakly coupled resonators and a first tunable rf filter.
Orthogonal modular embedded antenna, with manufacture and kits therefor
A system and method are disclosed which may comprise a composite resonating antenna structure which may comprise: a first substrate comprising a first portion of a flexible substrate comprising a first conductive layer forming a first resonating element on the first portion of a flexible substrate; a second substrate connected to a second portion of the flexible substrate to form a transition, with the first portion of the flexible substrate and the second substrate generally orthogonal to each other; and a second conductive layer attached to a third substrate, the second conductive layer shaped to include a ground plane section and a signal transmission line carrying microwave frequency signals including a center frequency; wherein the first resonating element radiates a frequency equal to the center frequency based on first portion of the flexible substrate and the third substrate being generally orthogonal to each other.. .
Locking system for detecting and tracking the center frequency of absorption lines in gases
A method to detect a gas absorption line that includes alternately transmitting and sweeping two radio frequency (rf) signals through an absorption cell, wherein the two rf signals are transmitted at different frequencies separated by a range and are swept across a span of frequencies in a microwave and millimeter wave regions of a frequency spectrum. Receiving the rf signals by a receiver and analyzing the received signals by a closed loop system for relative absorption by a gas due to an absorption line of the gas in the span of the swept frequencies.
Variable frequency iteration mppt for resonant power converters
A method of maximum power point tracking (mppt) uses an mppt algorithm to determine a switching frequency for a resonant power converter, including initializing by setting an initial boundary frequency range that is divided into initial frequency sub-ranges bounded by initial frequencies including an initial center frequency and first and second initial bounding frequencies. A first iteration includes measuring initial powers at the initial frequencies to determine a maximum power initial frequency that is used to set a first reduced frequency search range centered or bounded by the maximum power initial frequency including at least a first additional bounding frequency.
Motor control device for suppressing natural vibrations
A frequency component extracting unit (15) extracts a frequency component included in a control signal at a first frequency step size. A frequency detection unit (16) detects, from the extracted frequency component, a frequency corresponding to a natural frequency of a target object constituted of a motor (3) and a driven member (4).
Jammer resistant noise cancelling receiver front end
Techniques for providing a jammer-resistant noise-cancelling receiver front end with band-pass impedance matching and good power efficiency. In an aspect, the center frequency of the band-pass impedance matching advantageously tracks the local oscillator frequency.
Dynamically detecting resonating frequencies of resonating structures
There is described herein a real-time scheme, implementable in software, hardware, or a combination thereof, to detect a resonating frequency of a structure from a sensed signal and dynamically set the center frequency of an adaptive compensator for effective attenuation of the resonating frequency.. .
Meta-meterial vibration energy harvester
A meta-material vibration energy harvester includes a housing element encapsulating a multiplicity of oscillators capable of harvesting a significant percentage of the total mechanical energy diffusely distributed throughout the vibrating structure, the harvester design resulting in a rapid transfer of mechanical energy entering it via the housing element from the element to the oscillators wherein the energy remains trapped while accumulating over an extended time, the percentage of energy transfer primarily depending on the ratios of the sum of the oscillator masses to the sum of the housing mass and of the measure of the mass of the vibrating structure and of the width of the band spanned by the oscillators to its center frequency, both the relevant measure of the vibrating structure mass and the values of the mass and frequency ratios that maximize the percentage of internal energy transfer depending on the harvesting scenario.. .
Method to optimize the communication parameters between an access point and at least one client device
A method to optimize the communication on a channel between an access point and at least one client device, said channel being characterized by a center frequency and a bandwidth, comprises: establishing a connection on a first channel according to a first center frequency and a first bandwidth; exchanging data through this first channel between the access point and the client device; monitoring a first interference level on the first channel; the access point, while the data are exchanged, executes: informing the client device to switch to a second channel having a different center frequency and/or a different bandwidth; determining a second interference level on the second channel; comparing the first interference level with the second interference level; deciding to switch back or keep the second channel based on the comparison.. .
Flat-top tunable filter
A tunable plc optical filter having sequentially connected thermally tunable mach-zehnder (mz) interferometers is described. The cascade of mz interferometers, each having a free spectral ranges matching itu frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other itu frequency.
Millimeter-wave band spectrum analysis device and analysis method
An input signal sx in a first millimeter-wave frequency band higher than 100 ghz is input to a millimeter-wave band filter 20 in which a pair of radio wave half mirrors 30a and 30b so as to opposite to each other and which performs a resonance operation. A signal component sa corresponding to the resonance frequency of the filter is extracted, is mixed with a first local signal l1 with a fixed frequency, and is converted into a signal in a second frequency band.
Extremely high frequency (ehf) distributed antenna systems, and related components and methods
Extremely high frequency (ehf) distributed antenna systems and related components and methods are disclosed. In one embodiment, a base unit for distributing ehf modulated data signals to a rau(s) is provided.
Galvanically isolated, directional coupler
A galvanically isolated, directional coupler, especially for in- and out-coupling of high-frequency measurement signals of a radar fill-level measuring device, wherein two mutually engaging, oppositely bent, conductive traces are provided, wherein the two oppositely bent, conductive traces are so arranged that that they couple with one another over a region of a quarter wavelength (λ/4) of the wavelength associated with the center frequency of the measuring signals and form two groups of laterally coupled, conductive traces, and wherein curved conductive trace portions adjoin each of the two groups of laterally coupled, conductive traces, in each case, over a region, which is less than an eighth wavelength (λ/8) of the wavelength associated with the center frequency.. .
Methods and apparatuses for the detection of incontinence or other moisture, methods of fluid analysis, and multifunctional sensor systems
One embodiment of a method of interrogating a sensor to detect the presence of moisture on an occupant support comprises the steps of a) providing a moisture responsive sensor in a surveillance zone of the occupant support, the sensor being tuned to a center frequency; b) exciting the sensor with an electromagnetic signal having a frequency approximately equal to the center frequency; c) monitoring for a center frequency response from the sensor; d) comparing the center frequency response to an expected center frequency response; and e) if the center frequency response compares favorably to an expected center frequency response, issuing a first output consistent with the favorable comparison.. .
Fat fraction estimation using ultrasound with shear wave propagation
Fat fraction is estimated from shear wave propagation. Acoustic radiation force is used to generate a shear wave in tissue of interest.
Spread-spectrum voltage regulator
Described is an apparatus for providing spread-spectrum to a clock signal. The apparatus comprises: an oscillator to generate an output clock signal, the oscillator to receive an adjustable reference signal to adjust frequency of the output clock signal; a first circuit to provide a first signal indicative of a center frequency of the output clock signal; a second circuit to generate a switching waveform to provide spread-spectrum for the output clock signal; and a third circuit, coupled to the first and second circuits, to provide the adjustable reference signal according to the first signal and the switching waveform..
System and energy efficient measurement of sensor signal
A method for improving robustness of a capacitive sensor system has the following steps: a) operating the capacitive sensor system, wherein received sensor signals are filtered by a band-pass filter having a band-pass having a first center frequency; b) polling sensor data at a first rate using the sensor system; c) determining whether a polled sensor value is meeting a predetermined threshold; d) if the predetermined threshold is met: d1) polling sensor data at a second rate being higher than the first rate using the sensor system; d2) verifying that sensor data polled at the second rate are consistent; d3) if the sensor data polled at the second rate are inconsistent, then repeating at least step d2) wherein said band-pass filter is controlled to have a second center frequency.. .
Radar false alert reduction
A radar detector suppresses alerts from vehicle guidance systems, by sweeping for a consistent radar signal; the center frequency of the signal is stored and the detector suppresses warnings of radar signals near that frequency. The detector uses an enhanced method for suppression of signals near a known location of a false signal source; in the event the detector detects a radar signal and finds a matching stored false signal, the detector will first compare the strength of the received signal to a threshold strength that is computed based upon the distance of the detector from the stored false signal, and will only suppress signals below threshold.
Logarithmic amplifier with universal demodulation capabilities
A logarithmic amplifier (lda) is described that includes an amplifier configured to oscillate a modulated input signal, a feedback establishing a 180 degree phase shift between the amplifier input and the output and maintaining oscillation of the input signal, a parallel resonant circuit connected to the amplifier output causing the amplifier to resonate at or around a center frequency, and a controller connected to the amplifier input cyclically terminating oscillation of the input signal each time a pre-determined threshold of current is detected, the controller including a low pass filter configured to generate a second output signal having a repetition frequency. The lda may be used for am with or without a pll and/or a superhetrodyne.
Ultrasound diagnostic imaging apparatus
Disclosed is an ultrasound diagnostic imaging apparatus including an ultrasound probe which outputs transmission ultrasound toward a subject due to a pulse signal being input and which outputs a received signal by receiving reflected ultrasound from the subject, and a transmission unit which makes the ultrasound probe generate the transmission ultrasound by outputting a pulse signal whose drive waveform is formed of rectangular waves. The frequency power spectrum of the pulse signal has intensity peaks in a frequency band included in a transmission frequency band at −20 db of the ultrasound probe on a low frequency side and a high frequency side of a center frequency of the transmission frequency band, respectively, and intensity of a frequency region between the intensity peaks is −20 db or greater with a maximum value of intensity among the intensity peaks being a reference..
Apparatus and methods of frequency spectrum usage in a wireless communication system
Techniques of frequency spectrum usage in a wireless communication system include configuring two or more downlink carriers, each having a downlink carrier center frequency, to have a total occupied bandwidth that is constrained within an allocated downlink frequency spectrum. Further, the techniques include transmitting, to a user equipment (ue), two or more downlink carrier center frequency indicators that each identify a downlink carrier center frequency of each of the two or more downlink carriers.
Method and system for adaptive coding and modulation (acm) for supporting mesh network connectivity for multipoint networks
A method of provisioning a communications link between remote terminals within a hub-spoke network comprising receiving, by a first remote terminal, information about a second remote terminal from a hub, selecting, by the first remote terminal, a modulation factor, coding rate, symbol rate, center frequency, and power level based on the information received about the second remote terminal, transmitting, by the first remote terminal, a signal using at least one of the selected modulation factor, coding rate, symbol rate, center frequency, and power level, to the second remote terminal such that a communications link is created, and adjusting the modulation factor, coding rate, symbol rate, center frequency, or power level of the transmitted signal such that performance of the link is increased while maintaining a presence of the link.. .
Magnetic resonance imaging apparatus and magnetic resonance imaging method
In one embodiment, an mri apparatus (10) includes a gap calculating unit (65), a candidate calculating unit (66) and a sequence setting unit (61). The gap calculating unit calculates a gap between the center frequency of an rf pulse and a resonance center frequency, after start of a pulse sequence.
Optical signal processing apparatus, transmission apparatus, and optical signal processing method
An optical signal processing apparatus includes: an optical frequency comb generation unit configured to generate an optical frequency comb; an extraction unit configured to extract a plurality of optical components having a certain frequency interval between the optical components from the optical frequency comb; and an optical carrier generation unit configured to multiplex the plurality of optical components with reference light to thereby generate an optical carrier having a center frequency away from the center frequency of the reference light by an integer multiple of the frequency interval.. .
Magnetic resonance imaging apparatus
A magnetic resonance imaging apparatus of an embodiment includes: an imaging condition setting section configured to set an imaging condition for a main scan, a preparatory scan performing section configured to repeat a preparatory scan to be performed by the use of the imaging condition for a main scan and a changeably inputted center frequency so as to generate a preparatory image in real time, a display section on which the preparatory image can be displayed in real time, an optimum center frequency setting section configured to change the center frequency so as to change a situation in which a banding artifact appears and configured to set an optimum center frequency according to a user operation based on an observation of the preparatory image, and a main scan performing section configured to reconstruct an image for a diagnosis by using the optimum center frequency having been set.. .
Dual-band antenna of wireless communication apparatus
A dual-band antenna of a wireless communication apparatus includes a first radiation part for receiving or transmitting signals at a first frequency band; a second radiation part for generating a coupling effect together with the first radiation part to receive or transmit signals at a second frequency band having a center frequency lower than a center frequency of the first frequency band, wherein the second radiation part comprises multiple radiation sections, and at least one of the multiple radiation sections is positioned on a first plane; a feeding element for coupling with a signal receiving terminal of the wireless communication apparatus; and a shorting element for coupling with a fixed-voltage region of the wireless communication apparatus. The first radiation part does not physically contact with the second radiation part, and at least a portion of the first radiation part is not positioned on the first plane..
Tunable filter devices and methods
Analog interference filter devices and methods for isolation of desirable portions of a radio frequency signal. Signal compensation is used to provide desirable center frequency, passband width, ripple, rolloff, stopband and distortion performance.
Method for designing band pass delta-sigma modulator, band pass delta-sigma modulator, signal processing device, and radio transceiver
F0 is a center frequency of a quantization noise stop band of the band pass delta-sigma modulator.. .
Communication device and communication system
A transmitter includes a generation section that generates a baseband ofdm signal based on transmission data, and a transmission section that transmits a communication signal that is based on a real-part signal that is obtained by removing an imaginary-part signal from the baseband ofdm signal. In the baseband ofdm signal, the data signal including the transmission data is superimposed on subcarriers that are given numbers equal to or less than n/2−1, and the data signal is not superimposed on subcarriers that are given numbers more than n/2−1, where n (n is an integer) subcarriers included in the baseband ofdm signal are numbered by integers from 0 to n−1 in ascending order with respect to the center frequency of each subcarrier..
Method and system for frequency reuse in wireless relay scenario
The disclosure provides a method for frequency reuse in a wireless relay scenario, wherein a center frequency spectrum, an edge frequency spectrum and a random access frequency spectrum are pre-allocated to a cell according to a scenario parameter in the cell; load conditions of all mobile stations (mss) covered by each relay station (rs) in the cell is calculated and reported to a base station (bs); the bs allocates the random access frequency spectrum to an rs according to load conditions of all rss and schedules mss. The disclosure also provides a system for frequency reuse in a wireless relay scenario.
Synthetic aperture image reconstruction system in a patient interface module (pim)
A field programmable gate array (fpga) circuit including a quadrature internal conditioning circuit is provided. The circuit having a buffer circuit; and a reconstruction engine circuit, wherein the reconstruction engine circuit includes: a circuit to measure a phase of a signal; and a flavor interpolation circuit; wherein: the circuit to measure the phase of a signal includes digitization points forming two complex numbers for each cycle of the center frequency of the signal.
Systems and method to substantially mitigate ac stark shift effects in a sensor system
One embodiment includes a sensor system. The system includes a cell system comprising a pump laser configured to generate a pump beam to polarize alkali metal particles enclosed within a sensor cell.
Bonded pseudo hemispherical beam operation for spot beam environments
A method of creating a pseudo hemispherical beam using a plurality of individual spot beams comprising receiving by a single router or packet processor, user data from a plurality of users, processing the user data by the single router or packet processor using a qos logic such that a single output comprising a plurality of queues of data results, each queue of data comprising data designated for transmission only to one or more predetermined remote receivers, modulating the plurality of queues of data received using a multiple-carrier modulator such that a single output comprising a plurality of individual spot beams results, wherein each individual spot beam has a unique center frequency and carrier signal configuration, and transmitting the plurality of individual spot beams to a repeating relay configured to transmit each individual spot beam to the one or more predetermined remote receivers.. .
Methods of processing a radio frequency signal, signal processing devices for carrying out the methods, radio frequency front-ends, radio receivers and gnss receivers
A radio frequency signal is frequency-translated to form a complex first intermediate signal where a frequency corresponding to a gps center frequency is at an intermediate frequency. In a multiplexing conversion unit a complex multiplexed conversion signal which assumes different conversion frequencies is derived from a clock signal where the frequency of the latter is divided alternately by one of two divisors in a divider circuit and further by two in a phase shifter.
Automatic center frequency and span setting in a test and measurement instrument
A test and measurement instrument having initial display center frequency and span settings and configured to process an input signal is disclosed. The test and measurement instrument includes a processor configured to digitize the input signal and locate a primary peak and determine a primary peak center frequency of the input signal.
Method, system and program product for detecting wireless interferers
A method, system and program product comprise generating spectral samples from at least one radio communication device being configured to be operable as an observer of transmissions within a frequency band divided into one or more sub-bands associated with communications of the radio communication device. The spectral samples at least comprise signal levels and timing information for observed signals within the sub-bands.
Iphone frequency sensor/magnifier application
Devices, using emitted acoustic signals and received vibrations, determine resonant frequencies of a surface or other object, and determine useful information about that surface, including size, thickness, and material. Received vibrations include impulse vibrations from striking that surface with a finger or stylus, or from a frequency or from a swept-sinusoid emitted by the device.
Systems and methods for measuring high frequency resistance in a fuel cell system
System and methods for measuring operating parameters of a fuel cell system are presented. In certain embodiments, the systems and methods may be configured to measure a high frequency resistance of a fuel cell system.
Wireless communication device and wireless communication method
A wireless communication device includes a wireless communication module and an allocator. The wireless communication module wirelessly communicates with a plurality of other wireless communication devices.
Communication device and communication system
A preamble signal is an ofdm signal, and is a real-part signal obtained by removing an imaginary-part signal from a signal in the time domain that is generated by an ifft process being performed on a signal in the frequency domain obtained by assigning preamble data to subcarriers in accordance with a predetermined arrangement pattern. The predetermined arrangement pattern indicates that preamble data is assigned to any of subcarriers given numbers equal to or less than n/2−1 and the preamble data is not assigned to subcarriers given numbers more than n/2−1, where a plurality of subcarriers are numbered by integers from 0 to n−1 (n is an integer) in ascending order with respect to the center frequency of each subcarrier..
Elastic wave device
A reflector of the elastic wave resonator in an elastic wave device has first and second regions. The second region has third and fourth regions.
Dynamic operating bandwidth configuration for an envelope tracker
A communication device, such as a smart phone, receives operational parameters from a network controller. The operational parameters may include, as examples, bandwidth allocation, center frequency, and receive/transmit band assignments.
Method for performing a cooperative operation between heterogeneous networks and device for same
The present invention relates to a method for performing a cooperative operation between heterogeneous networks and a device for same. A method for a first type base station to perform a cooperative operation between heterogeneous networks in a wireless communication system includes receiving a downlink synchronization channel from at least one second type base station; obtaining an identifier (id) of the second type base station by using the received downlink synchronization channel; and transmitting at least one of a channel number and a bandwidth of a center frequency of the first type base station and the cell id of the second type base station to a server.
Glass antenna for vehicle
A glass antenna provided on vehicle side glass has a power feeding portion disposed at side portion of the side glass, a main element connected to the power feeding portion and a square bracket-shaped element whose one end is connected to some midpoint of the main element. When frequency band of fm broadcast wave received by the antenna is divided into two frequency bands with respect to its center frequency, wavelength of center frequency of frequency band of low frequency is λ, and wavelength of center frequency of frequency band of high frequency.
Method for measuring mechanical resonance frequency using servo driver
A method of measuring mechanical resonance frequency using a servo driver including the steps of: having the servo driver work under a torque control mode, by applying in the servo driver a preset torque drive signal, the motor drives the mechanical components in a microvibration state; collecting actual speed signals of the motor to obtain the actual speed signal sequence of the motor; the actual speed signal sequence of the motor being passed in sequence through a certain number of band-pass filters having a fixed pass-band frequency and different center frequencies to obtain filtered speed signals; the filtered speed signal sequences output from each of the band-pass filters being changed into absolute values and then accumulated to obtain accumulation values; comparing the accumulation values obtained from the signal sequences output from the certain number of band-pass filters, and the center frequency of the band-pass filter corresponding to the largest accumulation value being the mechanical resonance frequency. By using the method, an automatic measurement of the mechanical resonance frequency of a mechanical device can be achieved..
Single-cable automatic ird installation procedure
A method, apparatus, system, and computer program product for auto-installing an integrated receiver/decoder (ird) includes issuing an auto-installation command from the ird to an outdoor unit (odu) and receiving a plurality of tones from the odu in response to the auto-installation command, each tone representing a center frequency of available user bands (ubs). The auto-installation also includes acquiring a ub center frequency by the ird, requesting the odu to confirm a ub number corresponding to the acquired ub center frequency, and receiving confirmation from the odu that a ub number corresponds to the acquired ub center frequency.
Frequency tunable transmit/receive (tx/rx) antenna switch
A frequency tunable transmit/receive (tx/rx) antenna switch uses a tuned pin diode rf switch topology (e.g. Shunt, series or series-shunt).
Magnitude and phase response calibration of receivers
An integrated calibrator provides for magnitude and phase response calibration of rf receivers to produce amplitude flatness and phase linearity across the frequency range of the rf receiver by using a simple square law diode detector and a frequency-stepped two-tone source. A two-tone source generator provides two sinusoidal signals separated by a specified frequency delta about a center frequency.
Compact broadband impedance transformer
The present invention is directed to an impedance transformation device for use in a system having a characteristic system impedance, the device being characterized by a predetermined bandwidth having a center frequency. The device housing size is one-eighth wavelength of the center frequency.
Variable band pass filter device
A variable filter device has: a first series arm which is serially connected to a signal line, includes a variable capacitance and an inductance, and constitutes a series resonator; first and second parallel arms, which are connected between the signal line and the ground on both sides of the first series arm, each of which includes a variable capacitance and an inductance, and constitutes a grounded series resonator. The first series arm defines the center frequency of the pass band, and the first and second parallel arms define attenuation poles sandwiching the pass band..
On-chip optical reference cavity exhibiting reduced resonance center frequency fluctuations
An optical apparatus comprises a waveguide substrate and an optical reference cavity. The optical reference cavity comprises an optical waveguide formed on the waveguide substrate and arranged to form a closed loop greater than or about equal to 10 cm in length.
Method and apparatus of accessing channel in wireless communication system
A method and apparatus of accessing a channel including receiving, by a device, an operation element for setting up or switching at least one channel from an access point (ap), the operation element including a channel type field indicating whether the at least one channel is either a single channel or multiple channels, and including two channel center frequency segment fields indicating a channel center frequency of a primary and a secondary channel if the channel type field indicates that the channel is multiple channels, determining whether the primary channel is idle during a first interval, determining whether the secondary channel is idle during a second interval if the primary channel is idle, and transmitting data by using the primary and secondary channels to the ap or at least one station in a basic service set (bss) if the primary and secondary channel are idle.. .
Optical channel monitor
In one example, an optical channel monitor includes a tunable filter, a deinterleaver, first and second optical receivers, and a control module. The tunable filter is configured to receive an optical signal having a plurality of channels spaced at a nominal channel spacing.
Optical channel monitor
In one example, an optical channel monitor includes a tunable filter, a deinterleaver, first and second optical receivers, and a control module. The tunable filter is configured to receive an optical signal having a plurality of channels spaced at a nominal channel spacing.