75 results about "Passband filter" patented technology

The invention discloses a dual-passband filtering coupler based on a dielectric resonant cavity, particularly relates to the technical field of wireless communication, and solves the technical problems that in the prior art, a cavity filter and a cavity coupler often work in a cascade mode, and a matching network needs to be additionally configured between the cavity filter and the cavity coupler, so that the hardware cost is high, and the occupied system space is large. According to the technical scheme, the coupler and the dual-passband filter are integrated in one device, the circuit size can be remarkably reduced, and cascade loss between the coupler and the dual-passband filter is eliminated. The high-performance index of the microwave circuit is guaranteed, effective balance between performance and cost is achieved, and the microwave circuit completely conforms to the development direction of miniaturization, high performance and low cost of a future communication system.

This invention belongs to the field of microwave passive device technology and discloses a dual-passband millimeter-wave filter power divider based on a gap waveguide, comprising a metal bottom cover layer and a metal top cover layer arranged from bottom to top; wherein, the metal top cover layer includes a top cover and a top cover frequency division structure disposed on the top cover; the metal bottom cover layer includes a bottom cover and a bottom cover frequency division structure, a filtering structure, and a power divider network structure disposed on the bottom cover. The dual-passband millimeter-wave filter power divider based on a gap waveguide provided by this invention solves the technical problems of existing dual-passband filter power dividers, such as high design optimization requirements, narrow dual-frequency bands, difficulty in flexibly changing frequency bands, and high processing requirements.

The invention relates to the technical field of communication, in particular to a miniaturized wide-passband filter based on an EMSIW and a microstrip resonator. According to the miniaturized wide-passband filter, the two EMSIW cavities are adopted, the size of the filter can be effectively reduced, high-order modes TE120, TE210, TE220 and TE130 cannot be propagated in the EMSIW cavities, and therefore the filter has a wide stop band. Two microstrip resonators are embedded at a coupling window between two EMSIW cavities, and four-order quasi-elliptical filtering response is realized under the condition that no extra circuit area is occupied. Compared with other EMSIW filters, the filter has the advantages of being small in size, wide in passband, wide in stop band and good in selectivity, and has potential application value in a communication system.

The embodiment of the utility model relates to the technical field of communication, and particularly discloses a dual-passband filter and communication equipment, the dual-passband filter comprises a substrate and a topological structure, and the topological structure is arranged on the substrate. The topological structure comprises an input end, an output end, a first parallel line, a first microstrip line, a second microstrip line, a third microstrip line, a fourth microstrip line, a first open-circuit branch knot and a second open-circuit branch knot, the input end is connected with one end of the first parallel line, the other end of the first parallel line is connected with the output end, and the output end is connected with the third microstrip line. The other end of the first parallel line, the first micro-strip line, the second micro-strip line and the first open-circuit branch knot are connected in sequence, and one end of the first parallel line, the third micro-strip line, the fourth micro-strip line and the second open-circuit branch knot are connected in sequence. By means of the mode, the topological structure is simple and compact, and miniaturization of the dual-passband filter is facilitated.

This invention relates to the field of dual-passband filter technology and discloses an ultra-narrowband high-temperature superconducting symmetrical dual-channel filter. The invention establishes a high-order coupled topology based on CT and CQ units, enabling free adjustment of the zero positions between the two sub-passbands and the introduction of a pair of transmission zeros out of the dual-passband filter, thus achieving good sideband suppression between sub-passbands and throughout the entire dual-passband filter.

Methods and apparatus for optical filtering are provided. In one example, an apparatus includes a spatial light modulator (102) having a two-dimensional array of square, rectangular, or rhombic pixels, and a controller (110) coupled to the spatial light modulator (102). The controller (110) may be configured to write image data (114) representing an image to the spatial light modulator (102) to control the spatial light modulator (102) to display the image for a frame period, and during the frame period, spatially reposition the image across a plurality of locations over the array of pixels, each single position of the plurality of positions is maintained for a respective time period, wherein the respective time period is selected according to one or more non-negative coefficients of an anti-aliasing filter transfer function (402).

The invention discloses a single-cavity dual-passband SIW filter based on capacitance loading, which comprises a first metal layer, a first dielectric layer, a bonding layer, a second dielectric layer and a second metal layer which are stacked, and a second metalized through hole group with three interference through holes which are sequentially arranged along the Y direction, the second interference through hole is formed in the central axis of the SIW resonant cavity in the Z direction, and the first interference through hole and the third interference through hole are symmetrically formed in the two sides of the second interference through hole; the second dielectric layer is provided with a first metal column and a second metal column, and the first metal column and the second metal column are arranged in a central symmetry mode with the central axis of the second interference through hole as the center. According to the SIW filter provided by the invention, independent adjustment of two passbands can be realized in a single SIW resonant cavity, the requirements of miniaturization and passband selectivity are met, and the utilization rate of a cavity mode is improved.

The utility model discloses a topological structure which comprises a parallel line, a first microstrip line, a second microstrip line, a third microstrip line, a fourth microstrip line, a fifth microstrip line, a sixth microstrip line, a seventh microstrip line, an eighth microstrip line, a first open-circuit branch knot, a second open-circuit branch knot, an input end and an output end. The parallel line is composed of a first transmission line and a second transmission line which are arranged in parallel; the first end of the first transmission line is sequentially connected with the first microstrip line and the input end, and the second end of the first transmission line is sequentially connected with the second microstrip line, the third microstrip line, the fourth microstrip line and the first open-circuit branch knot. The first end of the second transmission line is sequentially connected with the fifth microstrip line, the sixth microstrip line, the seventh microstrip line and the second open circuit branch knot, and the second end of the second transmission line is sequentially connected with the eighth microstrip line and the output end. The utility model further discloses a wide dual-passband filter based on the topological structure, and the wide dual-passband filter has the advantage of miniaturization.

The utility model discloses a microstrip topological structure, which comprises a first transmission line, a second transmission line, a first microstrip line, a second microstrip line, a first open-circuit branch knot, a second open-circuit branch knot, an input end and an output end, and is characterized in that the first transmission line and the second transmission line are arranged in parallel to form a parallel line; the first end of the first transmission line is sequentially connected with the first microstrip line and the input end, the second end of the first transmission line is connected with the first open-circuit branch knot, the first end of the second transmission line is connected with the second open-circuit branch knot, and the second end of the second transmission line is sequentially connected with the second microstrip line and the output end. The utility model also discloses a dual-passband filter based on the microstrip topological structure, and the dual-passband filter has the advantage of wide passband.

The present invention provides a closed-loop RFID carrier automatic cancellation system, which includes a reader transmitter, a reader receiver, a frequency discriminator and phase detector module, a low-pass filter, a first-stage signal amplitude processing module, a second-stage signal amplitude processing module and a frequency divider. The reader transmitter is connected to the first input end of the frequency discriminator and phase detector module. The output end of the frequency discriminator and phase detector module is connected to the input end of the low-pass filter. The low-pass filter, the first-stage signal amplitude processing module, the second-stage signal amplitude processing module and the frequency divider are connected in sequence. The output end of the first-stage signal amplitude processing module is coupled to the reader receiver. The output end of the frequency divider is connected to the second input end of the frequency discriminator and phase detector module. The carrier signals generated inside the RFID reader are respectively connected to the reference ends of the first-stage signal amplitude processing module and the second-stage signal amplitude processing module. The present invention realizes the self-cancellation of the interference signals leaked from the transmitting link to the receiving link, thereby greatly improving the sensitivity of the receiver.

The present invention belongs to the field of electromagnetic fields and microwave technologies, and specifically relates to a design method for an asymmetric dual-band filter based on a frequency-variable coupling structure. The present invention applies the frequency-variable coupling structure to the design of an asymmetric dual-band filter based on two low-pass prototype functions. After converting the frequency-variable coupling matrix corresponding to the topological structure into a non-frequency-variable coupling matrix, all unknown parameters of the frequency-variable coupling matrix are optimized and solved through a constrained non-linear minimization function, thereby eliminating the original cross-coupling paths. The N-1 transmission zeros generated can be generated and independently controlled by the frequency-variable coupling structure, simplifying the topological structure of the filter and reducing the complexity of debugging. The present invention can synthesize dual-band filters with different orders, return losses, and bandwidths in different passbands and specified transmission zeros, realize an in-line topological structure, simplify the difficulty of filter design and simulation, and greatly improve the out-of-band rejection and isolation between passbands.

A system for filter enhancement, preferably including one or more analog taps and a controller, and optionally including one or more couplers. The system is preferably configured to integrate with a filter, such as a passband filter or other frequency-based filter. The system can be configured to integrate with an RF communication system, an RF front end, or any other suitable RF circuitry. A method for filter enhancement, preferably including configuring one or more analog taps, and optionally including calibrating a system for filter enhancement and / or receiving temperature information.

An optoelectronic oscillator (100) and a signal processing method, which relate to the technical field of optoelectronics. In the optoelectronic oscillator (100), an electro-optical modulator (110), an optoelectronic detector (120), a first filter (130) and a power divider (140) form an optoelectronic oscillation loop. Compared with a conventional single-passband filter, the first filter (130) in the optoelectronic oscillation loop has an additional low-frequency passband, and thus can excite a pulse train of the low-frequency passband and a pulse train of a bandpass band in the optoelectronic oscillation loop. Since the oscillation of a pulse signal can automatically narrow a pulse train to form an ultrashort pulse train, when the pulse train excited by the bandpass band has undergone pulse narrowing by means of an oscillation mechanism in the optoelectronic oscillation loop, the pulse train excited by the low-frequency passband may further undergo pulse narrowing, such that the optoelectronic oscillator (100) can generate a microwave pulse train which is shorter than that of a conventional optoelectronic oscillator, that is, an ultrashort microwave pulse train.

Filter modules having a wider passband are provided herein. In certain embodiments, the filter module comprises an input node; an output node; a filter disposed along a signal path extending from the input node to the output node; a strip line configured to generate an inductance between the filter and a ground such to increase a bandwidth of a passband of the filter module, the single strip line disposed on multiple layers, each of the multiple layers defined by a plurality of pulse-shaped) portions of the strip line disposed on a plane.

The invention belongs to the technical field of electromagnetic fields and microwaves, and particularly relates to a design method of an asymmetric three-passband filter based on a frequency-variable coupling structure. According to the method, a frequency-dependent coupling structure is applied to the design of the asymmetric three-passband filter based on the REMEZ-like algorithm, and after a frequency-dependent coupling matrix corresponding to a topological structure is converted into a non-frequency-dependent coupling matrix, all unknown parameters of the frequency-dependent coupling matrix are optimized and solved through a constrained nonlinear minimization function; therefore, an original cross coupling path is eliminated; and the generated N-1 transmission zeros can be generated and independently controlled by the frequency-variable coupling structure, so that the topological structure of the filter is simplified, and the debugging complexity is reduced. The three-passband filter with different orders, return losses and bandwidths can be synthesized in different passbands and specified transmission zero points, an in-line topological structure is achieved, the difficulty of filter design and simulation is lowered, and the degree of out-of-band rejection and isolation between the passbands is greatly improved.

The invention relates to the technical field of filters, and discloses a flat passband filter based on an equalizer and resonator integrated architecture, comprising a dielectric substrate; the input port and the output port are arranged on the two sides of the dielectric substrate; the resonator is coupled with the input port and the output port through gaps for feeding, so that a main path with band-pass response is formed; the equalizer is loaded at the strongest electric field of the resonator through a non-resonant node to form a dynamic coupling network; and the biasing circuit is used for adjusting the coupling strength of the input port and the output port, tuning the center frequency of the resonator, and tuning the dual-resonant frequency and gain amplitude of the equalizer. According to the invention, the all-parameter flexible and adjustable cooperative control capability is realized, and the independent regulation and control of the resonator center frequency, the equalizer dual-resonant frequency and the gain amplitude are realized through the cooperative design of the variable capacitance diode and the coupling structure.

The invention discloses a circuit and a method for improving interference of local oscillator phase discrimination stray on a receiver. The circuit comprises a clock input, a local oscillator unit, a filtering and amplifying unit and a frequency conversion unit which are connected in sequence. The filtering and amplifying unit is formed by connecting a pre-amplifier, an adjustable filtering unit and a post-amplifier in series; the adjustable filtering unit comprises a passband filtering and trap wave network to realize secondary suppression. The circuit can dynamically switch paths according to spurious offset, so that phase discrimination spurious is remarkably suppressed at a specific frequency point, local oscillator signals in a wide frequency range are compatible, low insertion loss and power fluctuation are kept, and the contradiction between bandwidth and performance is effectively balanced. The receiver local oscillator is realized by adopting conventional components and switch structures, does not need a special process, is easy to be integrated into an existing receiver local oscillator circuit, and has good compatibility.

Hybrid lattice filters with acoustic baluns are disclosed. In one aspect, a hybrid lattice filter may be formed using acoustic elements. The hybrid lattice filter may operate with acoustic baluns such as coupled resonator filters (CRF) or stacked crystal filters (SCF). To achieve the desired common mode rejection, an additional rejection or low common mode intermediate impedance network may be supplied between the acoustic balun and the hybrid lattice filter. By combining the acoustic balun with the low common-mode intermediate impedance network and the hybrid lattice filter, a passband filter with a desired bandwidth may be created.

The application discloses a dual-passband filter based on a copper-based micro-processing technology, which comprises a coaxial outer conductor and a coaxial inner conductor located inside the coaxial outer conductor, an input end feeder and an output end feeder are connected to the coaxial inner conductor, the coaxial inner conductor comprises a first quarter-wavelength transmission line, a second quarter-wavelength transmission line, a first half-wavelength transmission line and a second half-wavelength transmission line, the first quarter-wavelength transmission line and the second quarter-wavelength transmission line are coupled with the first half-wavelength transmission line and the second half-wavelength transmission line at the same time, and the first half-wavelength transmission line and the second half-wavelength transmission line are coupled with each other. The application has the beneficial effects that the transmission loss is small, and the signal shielding property is high.

The embodiment of the utility model relates to the technical field of communication equipment, and particularly discloses a topological structure, a wide dual-passband filter and communication equipment, comprising a first parallel five-line and a second parallel five-line which are connected in sequence, and a first microstrip line and a sixth microstrip line which are symmetrically connected between the first parallel five-line and the second parallel five-line, the first micro-strip line is symmetrically connected with the second micro-strip line and the fourth micro-strip line, the second micro-strip line is sequentially connected with the third micro-strip line and the first short-circuit branch, the first short-circuit branch is grounded, the fourth micro-strip line is sequentially connected with the fifth micro-strip line and the second short-circuit branch, the second short-circuit branch is grounded, and the sixth micro-strip line is symmetrically connected with the seventh micro-strip line and the ninth micro-strip line. The seventh microstrip line is sequentially connected with the eighth microstrip line and a third short-circuit branch, the third short-circuit branch is grounded, the ninth microstrip line is sequentially connected with the tenth microstrip line and a fourth short-circuit branch, and the fourth short-circuit branch is grounded. Through the above mode, the embodiment of the utility model can obtain the wide dual-passband filter with small size and high selectivity based on the topological structure design.

The invention provides a photoelectric oscillator and a signal processing method. The invention relates to the technical field of photoelectricity, and in the photoelectric oscillator, an electro-optical modulator, a photoelectric detector, a first filter and a power divider form a photoelectric oscillation loop. Compared with a conventional single-passband filter, the first filter in the photoelectric oscillation loop has the advantages that a low-frequency passband is added, and a pulse sequence of the low-frequency passband and a band-pass passband can be excited in the photoelectric oscillation loop. Due to the fact that oscillation of the pulse signal can automatically narrow the pulse sequence to form the ultra-short pulse sequence, on the premise that the pulse sequence excited by the band-pass passband passes through an oscillation mechanism in the photoelectric oscillation loop to narrow the pulse, the pulse sequence excited by the low-frequency passband can further narrow the pulse, and the ultra-short pulse sequence is formed. Therefore, the photoelectric oscillator can generate a microwave pulse sequence which is shorter than that of a conventional photoelectric oscillator, namely an ultra-short microwave pulse sequence.

The invention discloses an AMC loaded dual-passband waveguide filter for satellite communication, particularly relates to the technical field of wireless communication, and solves the problem that although a metal waveguide dual-passband filter is widely applied to the field of satellite communication due to the advantages of low loss, large power capacity, high Qu value and the like in the prior art, the filter cannot be applied to the field of satellite communication. However, the defect of huge volume also exists in the prior art. According to the technical scheme, resonant cavities are arranged, and the two resonant cavities are coupled through a coupling window. The input port and the output port both adopt WR-62 standard waveguides, are externally coupled with the resonant cavity through coupling windows respectively, and are the same in size; the relative size at the first high-order mode is reduced by more than 50%, and a good miniaturization design scheme is shown to meet the application requirement of satellite load miniaturization.

The invention provides a dual-passband filter. The dual-passband filter comprises a top metal layer, an upper dielectric plate, a middle metal layer, a lower dielectric plate and a bottom metal layer which are sequentially stacked from top to bottom, the middle metal layer comprises at least two capacitor loading patches; the metalized through hole array penetrates through the upper-layer dielectric plate and the lower-layer dielectric plate, the top end is connected with the top-layer metal layer, and the bottom end is connected with the bottom-layer metal layer; the at least two short-circuit conductive columns are located below the two capacitor loading patches respectively, the top ends of the short-circuit conductive columns are connected to the capacitor loading patches, and the bottom ends of the short-circuit conductive columns are connected to the bottom metal layer; the top metal layer comprises a resonance part, and the edge of the resonance part is provided with a first window. The dual-passband filter provided by the invention realizes independent regulation and control of dual passbands while satisfying miniaturization.

The invention discloses a spectrum analysis system and a control method thereof, and relates to the technical field of digital signal processing, and the system comprises a signal input port, a power distribution device, an analysis device, a control device and a plurality of signal links. Wherein the signal link comprises a signal processing module and an analog-to-digital conversion module. The signal processing module comprises filtering links of a plurality of passbands, and the signal processing module is configured to selectively switch the filtering links connected between the power distribution device and the analog-to-digital conversion module. And the analysis device is used for performing spectrum analysis on the output signal of the analog-to-digital conversion module. The control device is configured to obtain an analysis frequency band of the analysis signal; determining a target signal link and a target filtering link of each analysis frequency band based on the matching condition of the passband of the filtering link and the analysis frequency band; and controlling the corresponding signal processing module to be switched to the corresponding target filtering link so as to obtain a spectrum analysis result. The problem that the spectral analysis effect of a spectral analysis system is poor can be solved.

The application provides a hybrid mode based substrate integrated waveguide dual-passband filter, belonging to the microwave field, comprising a top metal layer, a middle dielectric layer and a bottom metal layer arranged in sequence from top to bottom; the middle dielectric layer is provided with first to fourth resonant cavities in the form of isosceles right-angled triangles formed by uniformly arranged metal via columns along the diagonal and the parallel direction of the side of the middle dielectric layer; two gaps are respectively reserved on the metal via columns between the first resonant cavity and the second resonant cavity, between the second resonant cavity and the third resonant cavity and between the third resonant cavity and the fourth resonant cavity, one of the gaps is located at the right angle of the triangle, and the other gap is located at the middle of the right angle side of the triangle; two metal tuning columns are respectively arranged in the first resonant cavity and the fourth resonant cavity, and one metal tuning column is respectively arranged in the second resonant cavity and the third resonant cavity; the oblique sides of the first resonant cavity and the fourth resonant cavity are respectively connected with a microstrip line on the top metal layer; and the filter realizes the filtering effect of four-order dual-passband under the condition that the size of the filter is unchanged.

The application discloses a kind of topology structure of small center frequency ratio of double-passband filter and filter, and the topology structure includes microstrip line, one end of the microstrip line is symmetrically connected with the one end of first parallel five lines and the one end of second parallel five lines, the other end of the microstrip line is symmetrically connected with the one end of first short-circuit stub and the one end of second short-circuit stub;The other end of the first parallel five lines is connected with input end, the other end of the second parallel five lines is connected with output end, the other end of the first short-circuit stub and the other end of the second short-circuit stub are grounded respectively.The application solves the problem that the center frequency ratio of two channels of existing double-passband filter is large.

The invention discloses an on-chip optical switching structure based on a flat passband filter array and a control method of the on-chip optical switching structure. The on-chip optical switching structure comprises an input / output waveguide array, a wavelength division multiplexing optical switch array composed of flat passband filters and a switch control unit. The control method comprises the steps of coupling multi-wavelength signals through an input / output waveguide array, determining propagation paths of different wavelength signals through a dynamic multi-wavelength routing strategy, demultiplexing the multi-wavelength signals through an on-chip reconfigurable flat passband filter, recombining the signals of different wavelengths of the same target port at the same time, and combining the signals of different wavelengths with the same target port at the same time. And the optical switch array is calibrated by combining optical power measurement signal feedback, so that full-automatic, low-loss and low-crosstalk switching of multi-wavelength high-speed signals is realized. The complexity of the on-chip wavelength division multiplexing optical switch array and the power consumption of a control system can be effectively reduced, and the bandwidth density of a chip is improved.

The invention relates to a flat passband filter circuit based on high-order cascading. The circuit comprises a high-order high-pass filtering module and a high-order low-pass filtering module which are cascaded in sequence to form a one-way processing path from a signal input end to a signal output end. Wherein the orders of the high-pass module and the low-pass module are not less than 6, and the cut-off frequencies of the high-pass module and the low-pass module are respectively set as the lower limit and the upper limit of a passband, so that a flat passband range is cooperatively defined. A Sallen-Key Butterworth structure is preferably adopted, and resistance-capacitance parameters of all levels are optimized, so that the excellent performance that the amplitude fluctuation in a passband is less than + / -0.5 dB and the roll-off rate of a transition band is greater than 80dB / octave is realized while high selectivity is ensured. The filter circuit provided by the invention effectively solves the contradiction between uneven passband and smooth transition band of the traditional band-pass filter, and is suitable for a precision electronic system with high requirements on signal fidelity and adjacent channel suppression.

Methods and apparatus for optical filtering. In one example, a device includes a spatial light modulator having a two-dimensional array of square, rectangular, or diamond pixels, and a controller coupled to the spatial light modulator. The controller can be configured to write image data representing an image to the spatial light modulator to control the spatial light modulator to display the image for a frame period, and during the frame period, spatially reposition the image on the array of pixels over a plurality of positions, each individual position of the plurality of positions being maintained for a respective time period, wherein the respective time period is selected according to one or more non-negative coefficients of an anti-aliasing filter transfer function.

The present invention discloses a bandwidth-reconfigurable low-pass filter, comprising: a resonant circuit, a control circuit, and a filter circuit; wherein the resonant circuit and the control circuit constitute a magnetically coupled resonator; the magnetically coupled resonator is used to generate a tunable zero point to change the passband of the filter; the filter circuit changes its passband based on the tunable zero point generated by the magnetically coupled resonator, with the passband range specifically determined by the tunable zero point; by changing the control voltage of the control circuit to change the tunable zero point, the passband width of the low-pass filter is changed, thereby achieving reconfiguration of the low-pass filter. The present invention utilizes the resonant circuit and the control circuit to form a magnetically coupled resonator. Simply by changing the control voltage introduced by the magnetically coupled resonator, the passband width of the filter can be changed, and the filter has a large reconfiguration range; the magnetically coupled resonator achieves bandwidth reconfiguration using only a small layout area.