297 results about "Switched filters" patented technology

A switched filter signal processing system includes an input terminal for receiving an input signal conveying first signal information in a first time phase and second signal information in a different second time phase. Desired information represents the difference between the first and second signal information. A multiplexed switch filter filters the input signal in the first phase with a first filter to obtain the first signal information and filters the input signal in the different second time phase with a second filter to obtain the second signal information. The system also includes a common filter component, which is shared by the first and second filter, and respective second filter components for the first and second filters. A controller controls the multiplexed switch filter to couple the common filter component to the second filter component of said first filter in said first time phase and to couple the common filter component to the second filter component of the second filter in the second time phase.

A power conversion system comprises a power converter comprising a plurality of semiconductor power switches, an LC filter coupled between an output of the power converter and an electric grid, and a power conversion control system. The LC filter comprises an inductor coupled in series to the electric grid, and a capacitor. The LC filter and the grid result in an equivalent LC circuit comprising an impedance of the LC filter and an impedance of the electric grid. The power conversion control system comprises a damper and a converter controller. The damper receives an LC filter signal and an equivalent LC circuit impedance signal and generates a damping signal. The converter controller receives a current or voltage reference signal, a current or voltage command signal, and the damping signal to generate control signals for driving switching operations of the semiconductor power switches.

In the light source unit 3A, a switching filter section 14, which can switch the RGB filter for normal-light observation and a filter for fluorescent observation on the optical path, is installed in front of the lamp 12, where if the fluorescent image mode is selected, the excitation light in a part of the blue wavelength band is supplied to the electronic endoscope 2A, and the excitation light reflected by the subject side is shielded by the excitation light cut filter 27 in front of the CCD 28 so as to obtain the fluorescent image, and also the signal of the fluorescent image and the signals of the two reflected light images which are set in a predetermined wavelength band are passed through the image processing circuit 38, where a matrix circuit for appropriately allocating the color signals of the R, G and B channels is installed, and as a result, the images can be displayed on the monitor 5 in pseudo-colors in hues which allow easy identification of a normal tissue and a pathologically affected tissue.

A circuit system for wireless communications via two antennas. The circuit system includes a printed circuit board having a predetermined area devoid of a solder mask. According to the invention, an antenna switch, filter, and power amplifier are mounted on the printed circuit board within the predetermined area. The antenna switch connects the filter and the power amplifier with the two antennas. The filter blocks unwanted frequency components in an RF receive signal from either of the antennas. A transceiver is responsible for down-converting the RF receive signal a baseband receive signal and up-converting a baseband transmit signal to an RF transmit signal. A first matching network coupled between the filter and the transceiver transforms the RF receive signal from single-ended to differential. Likewise, a second matching network coupled between the transceiver and the power amplifier transforms the RF transmit signal from differential to single-ended.

The invention discloses a method for realizing down conversion of a radio frequency (RF) spectrometer by narrow-band local oscillation and switch filtering. RF down-conversion fully utilizes three frequency coordinating modes and divides RF signals into five wave bands for down-conversion; utilizing switch filtering to realize frequency selection of the signal of different wave bands, so that thefirst local oscillation has narrow frequency span and low frequency; utilizing a plurality of band-pass filters in high wave band to realize frequency selection and frequency tuning, so that the design of the RF band filter is easy to realize. The invention has the advantages of simple and easy design, low cost and the like, and can be widely applied in down-conversion modules of economical and hand-hold RF spectrometers, RF receivers and RF network analyzers.

An improved switched filter up-sampling mechanism for scalable video coding. A filter switching mechanism of the present invention takes advantage of the best performance of each of the filters in a collaborative manner. The switching process of the present invention can be generalized to more filter choices and potentially relieve the computational complexity due to the added freedom and flexibility of filter choices.

A switching filter module for dynamic selection of N channels is provided. In the switching filter module, each of N double-channel selection filters passes the frequency bandwidths of two of successive first to Nth channels having predetermined frequency bandwidths, and one or more 2-way and 3-way switches connect the double-channel selection filters to one another. Each of the N double-channel selection filters is serially connected to at least one of the other double-channel selection filters and at least one 3-way switch.

The invention relates to a method for avoiding ping-pang switch, which comprises: based on the signal quality of present network of user terminal and target switch network, fixing the maximum allowed switch frequency; judging if allowing said switch, the real switch frequency is in the maximum value, if it is in said maximum value, allowing this switch; or else, rejecting said switch. The invention also discloses a device with ping-pang switch filter function whose network switch alarm module has ping-pang switch filter function. The invention can effectively reduce the ping-pang switch frequency generated at the edge of dual-network cover, and release the impact on the network processing ability when leading in the region transfer calling function.

The invention discloses a device and a method of automatically recognizing a candid camera. The device comprises a lighting source, a filter switcher, an image pickup device, an image processor and a control circuit, wherein the lighting source emits visible light and infrared light to irradiate on a to-be-detected area; the filter switcher can switch filters in turn to the front end of the image pickup device to enable the image pickup device to acquire visible light and infrared light images; the image processor compares a brightness difference between the infrared light image and the visible light image and a threshold, and whether a candid camera exists is judged; and the control circuit sends a control instruction to the above parts according to a self-stored program. Through the device and the method of the invention, an illegal photographing behavior can be recognized in an unattended and real-time mode, and the safety of the privacy of people and trade secrets can be effectively protected.

The invention discloses a density-adaptive image salt-pepper noise switching filtering method, which comprises the following steps of: training a plurality of neural networks adaptable to the accurate detection of noise positions under certain noise densities by using training images with different noise densities; rapidly and roughly evaluating the salt-pepper noise densities of the images; selecting corresponding neural networks according to the evaluated salt-pepper noise densities to perform accurate noise detection on the images; and performing window-adaptive switch weighted mean filtering on the images according to the accurately detected noise positions. By the method, the magnitudes of the noise densities can be automatically judged, and the accurate noise detection can be performed by adopting the corresponding neural networks for the densities with different magnitudes.

A radiographic image capturing apparatus includes a photodetector substrate, a scintillator, a switching filter, and a resetting light source, which are arranged successively in this order. If the switching filter is made permeable to resetting light from the resetting light source, the switching filter allows resetting light to be applied to the photodetector substrate through the scintillator, whereas, if the switching filter is made impermeable to the resetting light, the switching filter reflects at least a fluorescence, which is converted from radiation by the scintillator, toward the photodetector substrate.

The present invention relates to systems and methods that reduce quadra-phase shift key (QPSK) modulator assembly size, cost and complexity via employing microwave monolithic integrated circuit (MMIC) technology. The systems and methods provide MMICs that include positive-intrinsic-negative (PIN) diodes as phase shifters (e.g., binary, reflective, hybrid and switched filter) that mitigate the tight thermal control, complex drive electronics and calibration routines associated with conventional ferrite phase shifters. The systems and methods can be employed in connection with antenna auto-tracking system such as those associated with satellites, aircrafts and spacecrafts. Employing MMIC technology provides for chips that can be consistently fabricated for extremely high frequency (EHF) operation, and that can increase system performance via mitigating parasitic reactance.

The invention discloses a control method for high-power reactive and harmonic dynamic hybrid compensation method. The hybrid compensation system comprises an SVG (static var generator), a TSF (thyristor switched filter) group and a controller, and the SVG and TSFs are parallelly connected to a grid. The three-phase current of the grid between the SVG and the TSFs is taken as a detection object, voltage and current values collected by sensors are processed through the controller, switching signals of the TSFs are acquired according to hybrid logic judgment, most of the reactive power of loads is compensated in a graded manner, and specific subharmonic is filtered out; control parameters of the SVG are acquired according to an instantaneous-power theory, and the surplus reactive power and harmonic of the loads are continuously compensated. A cost-effective scheme for rapid continuous compensation of the high-power reactive and harmonic is provided, impact of switching of passive equipment on the grid can be completely avoided, and harmonic current is avoided flowing to the grid, so that the control method is energy saving, emission reducing, green, environment friendly, good in social and economical effectiveness, wide in application range and especially applicable to the field of oil drilling.

An integrated switched filterbank and method of forming an integrated switched filterbank is disclosed. One embodiment includes a switched filterbank that includes an active subassembly, a plurality of active devices mounted to the active subassembly, and a stripline filter subassembly stacked below the active subassembly. The stripline filter subassembly includes a plurality of stripline filters of varying passbands embedded therein, wherein the plurality of stripline filters are coupled to active devices mounted on the active subassembly through a set of contacts extending from the stripline filters through the active subassembly to at least one of the plurality of active devices.

The invention relates to a real IPv6 resource address filter check technique. Wherein, it is characterized in that: one filter at the outlet of autonomous edge route is distributed with a filter rule generate engine and filter engine cooperated with said route, while the first one will generate filter rule list with real source address filter strategy based on the communication report of autonomous control server, and switches filter strategy; said strategy comprises SPM, SAVE, and inlet filter, etc; the second one has internet control information protocol report processing module, sign processing module, and edge mark module, to check and filter the report from internal network interface of edge route transfer engine based on filter strategy. The invention can flexibly embed filter strategy and the filter rule list provides unique and effective data-level support for embedding filter strategy.

The invention is concerned with broadband low loss switch filter group of surface acoustic wave. The group relates to tow groups of multi-throw switch with one knife and some filters of surface acoustic wave. One group switch joins up the imports of some filters of surface acoustic wave, the other group joins up the fan-outs of some filters of surface acoustic wave and the tow groups of switch is corresponding to each other. The structure to said filter of surface acoustic wave is longitudinal coupling resonant to realize the low loss. Different channels adopt some different longitudinal coupling structure to get as same bandwidth as possible for each channel. The base plate is LiNbO3, LiTaO_3, and so on. This invention affords a kind of switch filter group of surface acoustic wave for broad band to communications system (single channel relative bandwidth is 2%-7.3%), low loss (containing the switch, less than 6.5dB) and higher stop-band limit (more than 40 dB ).

The present invention relates to a high frequency electromagnetic wave transmitter which comprises a frequency demultiplier, a gating switch, a filter, a transmission drive unit, a power amplification unit and an output end resonance loop which are in electric connection orderly. The output end resonance loop is connected with a transmission coil by a coupling transformer and forms an integral resonance loop together with the coupling transformer and the transmission coil. The transmitter uses the coupling transformer, temperature compensation, seven-step elliptic filter and a transistor C-class amplification circuit; compared with the prior art, the transmitter has the advantages of high transmission efficiency, good temperature characteristic, etc. The circuit design of the transmitter can be fit for various kinds of high frequency electromagnetic wave well logging tools with one or multiple transmission frequencies less than 15MHz and can work normally within a large temperature range between 25 DEG C and 150 DEG C.

The invention relates to a design method of an ultra-wideband single-conversion multi-channel digital receiving module. The ultra-wideband single-conversion multi-channel digital receiving module is composed of an analog receiving module body and a digital processing module body. The analog receiving module body processes 2<n>(n=1, 2, 3...) receiving signals and then synthesizes a radio-frequencysignal through a column-wise synthesizer, the radio-frequency signal passes through a section switch filter and then is subjected to frequency mixing and filtering, and a 6 GHz bandwidth wide frequency range signal and a frequency spectrum are shifted to an intermediate frequency of the range being 1-1.4 GHz. The digital processing module enables the input intermediate frequency signal with the bandwidth of up to 400 MHz to be subjected to AD sampling and analog-to-digital conversion, and the sampled signal is directly sent to an FPGA for signal preprocessing. After multiphase filtering channelization processing and amplitude-phase compensation are carried out, 2n-1 channel intermediate frequency digital signals are generated.

The invention provides an integrated optical circuit device for monitoring the temperature of turbine blades of an aero-engine. An integrated optical circuit system is used for measuring the surface temperature of turbine blades, and comprises a three-band temperature measurement optical path, a gas spectrum analyzing optical path, a data acquisition and processing system and a master controller. The infrared radiation emitted by a tested blade is divided into two parts after passing through the optical circuit system. The first part is received by a photoelectric detector after entering the three-band temperature measurement optical path, is processed by a filter circuit and an amplifying circuit and then is analyzed by the data acquisition and processing system. The second part of the infrared radiation enters the gas optical spectrum analyzing optical path. The gas absorption peak is analyzed. A switching controller switches optical filter wheels in the temperature measurement optical path. The integrated optical circuit device provides a gas spectrum analysis function, analyzes the gas absorption spectrum, switches the band used for temperature measurement as required, can avoid the gas absorption peak, reduces measurement errors, and switches filter lens according to use occasions, and provides single-band, dual-band, and three-band temperature measurement functions.

The invention provides a simple solution for a broadband transmitter/receiver for which the working bandwidth is split into at least two non-contiguous sub-bands. The invention uses a filtering means 50 which comprises at least two band-pass filters 51 and 52 provided with switching means 53 and 54. The use of two switched filters 51 and 52 makes it possible to use a single synthesizer 6 to scan two sub-bands of the working bandwidth. The frequency synthesizer 6 operates for one sub-band in supradyne mode and for the other sub-band in infradyne mode. In a variant, the invention uses a third filter and divides the bandwidth into three sub-bands.