87 results about "Transmission zeros" patented technology

An IPD high-selectivity band-pass filter based on a weak coupling transformer technology comprises an LC parallel resonance circuit, an LC series resonance circuit, an LC parallel resonance circuit and a fourth capacitor C4, and inductors in the LC parallel resonance circuit and inductors in the LC parallel resonance circuit have a weak transformer coupling relation; the coupling coefficient required by the weak coupling transformer provided by the invention is very small and can be realized in a mode of adjacently placing metals on the same layer, so that the structural complexity of the filter is effectively reduced; the band-pass filter is based on an IPD technology, an extra decoupling equivalent inductor is introduced through a weak transformer coupling technology, the extra decoupling equivalent inductor and a parallel capacitor which is connected between the input end and the output end of the filter in a bridging mode form a new resonance path, and a transmission zero point is introduced into an upper stop band and a lower stop band of the filter respectively to improve the selectivity of the filter. According to the invention, the selectivity of the filter can be effectively improved on the premise of not additionally introducing an inductance element and not increasing the order of the filter.

The invention discloses an intermediate frequency filter chip based on a gallium arsenide IPD process, which adopts the GaAs IPD process with three metal layers and comprises six resonators, twelve capacitors and three metalized grounding holes. The six resonators are composed of capacitors C1-C6 and inductors L1-L6 which are connected in series / in parallel, the inductors are all of self-built octagonal structures, and wiring is only conducted on the middle layer and the uppermost metal layer; a branch series capacitor Ca-Cc and a main parallel capacitor Cd-Cf respectively form six transmission zeros outside a low-frequency band and a high-frequency band. According to the invention, the characteristics of small size and wide band of the filter chip are realized, the loss is reduced, the in-band flatness is improved, and the filter chip has high frequency selectivity and high out-of-band rejection capability.

The invention discloses a high-selectivity waveguide filter based on a nonlinear frequency-variable coupling structure, which comprises three rectangular waveguide resonant cavities, an input waveguide port and an output waveguide port, and the first coupling metal column, the first coupling diaphragm, the first coupling metal block and the first metal baffle plate between the first resonant cavity and the second resonant cavity jointly form a first group of nonlinear frequency change coupling structures. And a second coupling metal column, a second coupling diaphragm, a second coupling metal block and a second metal baffle plate between the second rectangular waveguide resonant cavity and the third rectangular waveguide resonant cavity jointly form a second group of nonlinear frequency change coupling structures. The two groups of nonlinear frequency-variable coupling structures are used for coupling the three rectangular waveguide resonant cavities, and a reflection zero point and two transmission zero points are introduced into each rectangular waveguide resonant cavity, so that the filter response is a five-order Chebyshev response with four transmission zero points. The filter has the advantages of being compact in structure, high in selectivity, good in out-of-band rejection performance, simple in structure, easy to expand and the like, and has a good application prospect.

The invention belongs to the technical field of integrated circuits, and discloses a high-selectivity constant-bandwidth reconfigurable filter chip based on a GaAs (gallium arsenide) process, which comprises a dielectric substrate, a multilayer metal structure, a plurality of folded opening-shaped metal microstrip lines, a plurality of grounding metal columns, a variable capacitance diode, an MIM (metal injection molding) capacitor and the like. Resonance is realized in a mode of combining electric coupling and magnetic coupling, a variable capacitance diode is utilized to tune the center frequency, and the bandwidth is kept constant in the tuning process. Transmission zeros are introduced at two sides of a passband through cross coupling, so that the frequency selectivity and the spectrum management capability are remarkably improved, and meanwhile, the optimization of the microstrip interconnection structure effectively reduces the system loss. According to the invention, the strict requirements of a modern radio frequency communication system on miniaturization, high performance and high selectivity can be met, and extremely high adjustability and adaptability are achieved.

This disclosure provides a filter and a multiplexer including the same. The filter according to this disclosure includes: at least one series resonator unit connected in series between an input node and an output node, comprising a series resonator or comprising a series resonator and an inductor and / or capacitor connected in parallel or in series therewith; and at least one parallel resonator unit connected in parallel between a connection node and a ground node, comprising a parallel resonator or comprising a parallel resonator and an inductor and / or capacitor connected in parallel or in series therewith, the connection node being a node at the input and / or output of at least one series resonator unit and / or at least one parallel resonator unit being a composite resonator comprising a resonator. The filter according to this disclosure and the multiplexer including the filter can form more out-of-band transmission zeros in the filter's frequency response curve, thereby enhancing out-of-band attenuation.

The invention discloses a lumped element and acoustic resonator mixed filtering balun and radio frequency front end system, which comprises a first module, a second module, a third module, a fourth module, a fifth module, a sixth module and a seventh module, and is characterized in that the first module, the third module and the fourth module are acoustic-electric mixed modules and comprise lumped elements and acoustic resonators; the first module, the fifth module, the sixth module and the seventh module are used for forming a plurality of transmission zero points outside a passband of the filtering balun so as to enhance the selectivity and out-of-band rejection of the edge of the passband, and the second module, the fifth module, the sixth module and the seventh module are electric modules, are formed by lumped elements and are used for realizing the passband of the required filtering balun. Reflection loss caused by impedance mismatching when discrete devices are cascaded can be avoided, insertion loss of a system is remarkably reduced, the size and cost of the system are reduced, the broadband advantage of an electrical filter and the high selectivity advantage of an acoustic filter are integrated, and meanwhile the high-performance filtering balun which is miniaturized, large in bandwidth and high in selectivity is achieved.

An antenna, antenna module, and electronic device. An antenna includes a first dielectric layer, a second dielectric layer, and a third dielectric layer. The second dielectric layer and the third dielectric layer are disposed on a same side of the first dielectric layer. The second dielectric layer and the third dielectric layer are disposed at different layers. A first radiating element is disposed at the first dielectric layer. A feed line is disposed at the second dielectric layer which feeds the first radiating element. A split resonance unit is disposed at the third dielectric layer, and in signal connection with the feed line. The split resonance unit is disposed on an input port of the antenna. In response to the split resonance unit operating on a resonant frequency thereof, the split resonance unit generates a transmission zero near the resonant frequency of the split resonance unit.

The invention provides a dual-passband waveguide filter and a coupling topology thereof, the dual-passband waveguide filter comprises a metal structure, the interior of the metal structure comprises a torispherical cavity and two sections of feed waveguides, the torispherical cavity is divided into four quarter-spherical cavities by partition plate structures, and the quarter-spherical cavities are communicated with the feed waveguides. Every two adjacent quarter spherical cavities are in coupling connection through a coupling window, and the two feed waveguides are respectively in coupling connection with the two opposite quarter spherical cavities through coupling windows. The dual-passband waveguide filter coupling topology comprises a cellular structure with a resonant node and a non-resonant node, a metal structure is in a physical presentation form of the cellular structure, a quarter spherical cavity is the resonant node, a feed waveguide is the non-resonant node, and the metal structure is a metal structure. According to the coupling topology theory, dual-passband band-pass filtering response of any even order can be realized, and limited transmission zeros are introduced into the lower stop band and the upper stop band of the two passbands at the same time, so that the stop band performance of the dual-passband band-pass filtering response is improved.

The invention relates to the technical field of radio frequency devices, in particular to an amplitude limiter circuit structure integrated with a filtering function by a gallium arsenide process, and the circuit sequentially comprises a 50-ohm microstrip input matching section, a first-stage amplitude limiting filtering unit, a second-stage amplitude limiting filtering unit and an output matching section along a main transmission line, in the first stage, three forward PIN diodes and three reverse PIN diodes are stacked and connected to a main circuit in parallel, high power tolerance and symmetrical amplitude limiting capacity are achieved, and two low-frequency transmission zero points are formed by fusing a micro-strip grounding branch knot and an MIM capacitor resonator; in the second stage, two anti-parallel PIN diodes are matched with a grounding inductor to form a third transmission zero point, three groups of resonant structures are integrated, six transmission zero points are introduced, the filtering performance in a 12-18GHz frequency band is remarkably enhanced, a PIN diode parasitic capacitor and a microstrip inductive structure are skillfully utilized by the circuit to cooperatively realize filtering, extra passive elements are not needed, and the cost is low. The method is suitable for integrated protection of sensitive devices in a high-frequency radar and communication system.

The invention provides a third harmonic suppression film microstrip filter based on a mixed structure. Comprising a substrate, a pair of coplanar waveguide feeder lines used for being connected with an external circuit and playing a role in impedance matching, and a plurality of interdigital resonators used for generating passband characteristics of the filter, the hairpin resonator is used for generating a transmission zero point at the low end of the filter to improve low-end stop-band suppression, the 1 / 4 wavelength open-circuit lines are used for suppressing third harmonics of the filter, and the pair of coplanar waveguide feeder lines, the interdigital resonators, the hairpin resonator and the 1 / 4 wavelength open-circuit lines are all laid on the substrate. The plurality of interdigital resonators are located between the pair of coplanar waveguide feeders, the hairpin resonator is located between the plurality of interdigital resonators, the pair of coplanar waveguide feeders is connected with the interdigital resonators at two sides of the plurality of interdigital resonators, and the plurality of 1 / 4 wavelength open-circuit lines are connected with the pair of coplanar waveguide feeders in parallel.

This invention discloses a miniaturized, highly selective bandpass filter chip for multipath transmission, comprising an input port, an output port, a port matching network, five octagonal inductors (L1~L5), seven MIM capacitors (C1~C7), and one ground inductor Ls1. It includes a conventional filtering path (Path A) and a compact coupling path (Path B) connected in parallel between the input and output ports. The port matching network is composed of capacitors C4 and C7. Path A forms three resonant units by connecting capacitors C1~C3 in parallel with inductors L1~L3, which, together with capacitor C5, inductor L4, and ground inductor Ls1, constitute a basic bandpass structure and generate low-frequency transmission zeros. Path B forms a compact coupling network by connecting symmetrically coupled inductor L5 in parallel with capacitor C6, utilizing mutual inductance coupling to generate additional high-frequency transmission zeros. The filter chip is implemented using GaAs-based IPD technology to achieve fully lumped component integration, possessing advantages such as compact structure, high selectivity, stable performance, and high integration density.

This invention discloses a bandpass frequency-selective surface structure based on strongly coupled pairs, composed of multiple basic structural units. Each basic structural unit has a vertically symmetrical structure along its thickness direction. Both the upper and lower symmetrical portions include a first metal layer and a first dielectric layer in symmetrical positions. The first metal layer contains a first resonator pair, a second resonator pair, and a third resonator pair, each using metal patches as resonators. A second metal layer and a second dielectric layer, separated along the thickness direction of the basic structural unit and in asymmetrical positions, are disposed between the upper and lower symmetrical portions. The upper and lower symmetrical portions are connected by metal conductive posts. This invention operates stably at a center frequency of 5 GHz, introduces four transmission zeros, achieves a fourth-order frequency response within 8.4% of the relative bandwidth, has an insertion loss of less than 0.49 dB, and 40° angular stability, exhibiting superior performance.

This invention discloses a linear multi-zero cavity duplexer based on a hybrid resonator. The duplexer comprises a rectangular hollow metal cavity, a common signal terminal at the top of the cavity, and two signal branches on either side. The branches employ a hybrid cascaded structure of single-mode and dual-mode metal resonators, forming a linear topology without cross-coupling. The dual-mode metal resonator can operate simultaneously in inter-plate coupling mode and coaxial mode. The resonant mode order is set by pre-setting the internal inter-plate distance, allowing each branch to generate two preset transmission zeros. This invention achieves a six-pole filtering response using only four resonant cavities, forming a dual passband and generating four preset transmission zeros, ensuring high quality factor and high channel isolation while achieving device miniaturization. This invention features a simple structure, easy fabrication, and independently and precisely adjustable coupling parameters, making it suitable for 5G / 6G communication, emergency communication, and UAV-borne high-performance miniaturized RF front-end applications.

The invention provides a high-suppression passive reconfigurable intermediate-frequency filter based on a GaAs process, which comprises a high-order reconfigurable low-pass filter unit and a high-order reconfigurable high-pass filter unit which are in cascade connection, and is characterized in that the high-order reconfigurable low-pass filter unit is designed based on a seven-order low-pass elliptic function prototype and comprises a series branch and a parallel branch; the parallel branch comprises an adjustable capacitor and an inductor connected in series, bandwidth mode switching is achieved by adjusting the position of a transmission zero point, a fixed LC resonance circuit is introduced into the series branch to generate a fixed transmission zero point, and out-of-band rejection is enhanced; the high-order reconfigurable high-pass filter unit is designed based on a seven-order high-pass elliptic function prototype and comprises a series capacitor and a parallel grounding branch, and the parallel grounding branch comprises an inductor and an adjustable capacitor which are connected in series and is used for introducing a transmission zero point of a low-frequency stop band. According to the scheme, low insertion loss is kept while bandwidth mode switching is achieved, and the far-end out-of-band rejection capacity is remarkably improved.

The invention relates to the technical field of communication equipment, and discloses a frequency hopping filter with a hopping transmission zero point, a hopping control method and communication equipment. At least one resonant inductor of an LC resonant circuit of the frequency hopping filter is connected with a radio frequency switch feedback capacitor array in parallel; the frequency of a transmission zero point at a higher harmonic of the frequency hopping filter is controlled by controlling the opening and closing of a channel where each feedback capacitor in the radio frequency switch feedback capacitor array is located, so that the frequency of the transmission zero point changes along with the center frequency of the frequency hopping filter; and finally, far-end suppression, relative bandwidth stability and frequency hopping accuracy in a wide frequency range are improved.

The invention discloses a band-pass filter based on a three-dimensional hybrid disturbance technology. The band-pass filter comprises a base body, a filter circuit, a mixed disturbance structure, an input port and an output port, and the filter circuit is arranged in the base body and comprises a first capacitor, a first inductor, a second inductor and a second capacitor which are sequentially connected between the input port and the output port in series. The filter circuit further comprises a first parallel arm and a second parallel arm which are connected between the first inductor and the second inductor in parallel, the first parallel arm comprises a third inductor and a third capacitor, the second parallel arm comprises a fourth inductor and a fourth capacitor, and one end of the mixed disturbance structure is connected between the input port and the first capacitor. The other end of the hybrid disturbance structure is grounded, and the hybrid disturbance structure is used for generating a transmission zero point in a stop band of the filter. The band-pass filter can generate a controllable transmission zero point in a stop band.

This invention discloses a cross-shaped microstrip filter, belonging to the field of microwave RF passive device technology. The filter includes a dielectric substrate, an input microstrip line, an output microstrip line, two sets of series-arm resonant units, and two sets of parallel-arm resonant units. The series-arm resonant units are composed of microstrip inductors and interdigital capacitors connected in series, with the resonant frequency corresponding to the filter's center frequency. The parallel-arm resonant units are composed of microstrip inductors and surface-mount capacitors connected in series, generating low-frequency and high-frequency transmission zeros respectively. The four sets of resonant units converge at a common node to form a cross-shaped topology. This invention, through a modular cross-shaped architecture, allows direct mapping between the resonant units and the frequency response, simplifying debugging and increasing design efficiency. Modular cascading can achieve high-order filtering, significantly improving band-edge steepness and stopband suppression, making it suitable for microwave RF systems such as communication, radar, and satellite navigation.

The invention discloses a mixed lumped distributed five-order band-pass filter based on an LTCC technology. The mixed lumped distributed five-order band-pass filter comprises a ceramic substrate and an electrode located at the bottom of the ceramic substrate. The electrodes are periodically arranged and comprise an input electrode, an output electrode and a grounding electrode; a traditional five-order Chebyshev band-pass filter structure is adopted in the ceramic substrate, and the ceramic substrate comprises a first parallel resonator, a first series resonator, a second parallel resonator, a second series resonator and a third parallel resonator. On the basis, two cross coupling inductors L13 and L35 and three cross coupling capacitors C13, C35 and C15 are introduced, the number of transmission zero points of the band-pass filter is increased, the selectivity of the band-pass filter is greatly improved, and out-of-band rejection is deepened. The problems that a traditional LTCC multi-layer spiral inductor is large in occupied space, complex in design and debugging and high in manufacturing process requirement are solved.

The invention discloses a multi-frequency radio frequency filter based on diamond, and relates to the technical field of microwave communication. The filter comprises a diamond dielectric substrate, a pair of bent interdigital stepped impedance resonators arranged on the substrate and two sections of open-circuit branches loaded at low impedance sections of the resonators, and a 50-ohm microstrip line is adopted for feeding. By optimizing structural parameters, the filter forms three passbands, and four depth transmission zero points are generated at 4.23 GHz, 7.55 GHz, 10.84 GHz and 16.38 GHz by using open circuit branches, so that high-selectivity filtering and strong out-of-band rejection are realized. The high thermal conductivity and low dielectric loss of the diamond substrate significantly improve the heat dissipation performance, the power capacity and the quality factor of the device, and the SiO2 protection layer enhances the environmental reliability. The antenna is compact in structure, and is suitable for 5.8 GHz ISM, X-band satellite communication and Ku-band radar systems.

The invention belongs to the technical field of filters. The invention provides a high-selectivity rectangular micro-coaxial band-pass filter with a double-CT (Computed Tomography) structure. According to the embodiment of the invention, the first transmission line resonator, the second transmission line resonator and the third transmission line resonator form a CT structure, and the fourth transmission line resonator, the fifth transmission line resonator and the sixth transmission line resonator form a CT structure, so that a transmission zero point is introduced, and high selectivity of the device is realized; meanwhile, a transmission line resonator structure is matched and utilized to sequentially pass through seventh, eighth, ninth and tenth metal inner cores and a metal supporting structure to be converted from a horizontal plane to a vertical plane, and is combined with a first metal inner core boss and a second metal inner core boss at the upper ends of the eighth metal inner core and the tenth metal inner core; according to the band-pass filter disclosed by the invention, the coplanar waveguide interconnected with an external element is formed by the coplanar waveguide and the port on the shell, so that a micro coaxial line-coplanar waveguide switching structure is formed, the structure is beneficial to board-level interconnection integration of the band-pass filter and other devices, the application range of the band-pass filter is widened, and the band-pass filter has the advantages of low loss and high suppression degree.

A design method for a lumped narrowband IPD filter based on N+2 coupling theory is presented. This invention addresses the problems of existing methods for calculating transmission zero locations being difficult to apply to IPD processes and for quickly providing component values. The design method comprises: 1. Performing bandpass frequency transformation on the admittance matrix equation; 2. Setting the cross-coupling factor between resonators i and k in the coupled filter network as M. ik The cross-coupling factor M is characterized by a PI-type capacitor network. ik ; 3. When M ik When it is positive, it belongs to magnetic coupling, M ik When the value is negative, it indicates electrical coupling. Fourth, the designed narrowband IPD filter circuit undergoes evolution and simplification processing, including source impedance transformation, narrowband approximation of magnetic coupling, and negative capacitance narrowband approximation, to solve for the component values ​​of each element in the circuit structure. This invention starts from the topology of the coupled filter and utilizes various narrowband filter analysis methods to achieve the evolution and simplification of the circuit structure.

The application provides a lumped parameter topology for realizing generalized Chebyshev band-pass frequency response by using lumped parameter elements, which specifically includes two types of structures, GCL and GCB. The generalized Chebyshev band-pass frequency response includes two types of double-side generalized Chebyshev band-pass frequency response and single-side generalized Chebyshev band-pass frequency response. The response is characterized in that the response amplitude in the passband is equal ripple fluctuation, has three transmission poles, and two transmission zeros can be flexibly placed at limited frequencies, which are any positive frequencies except zero frequency and infinite frequency. The GCL structure is used for realizing double-side generalized Chebyshev band-pass frequency response, and the GCB structure is used for realizing single-side generalized Chebyshev band-pass frequency response. The application effectively overcomes the limitations of the prior art, and realizes more complex frequency response by flexibly setting transmission zeros.

The invention relates to a filter, in particular to a method for setting a transmission zero point of a comb line filter, which comprises the following steps of: generating electric coupling and magnetic coupling by utilizing parasitic coupling between resonators, and adjusting the intensity of the electric coupling and the intensity of the magnetic coupling, so that the filter generates the transmission zero point. According to the method for setting the transmission zero points of the comb line filter, the transmission zero point scheme can be flexibly set, the zero points are flexibly arranged at the high end and the low end of a filter passband, filter suppression is increased, the filter series is reduced, and the size of an antenna combiner is reduced.

The invention provides a cross coupling structure for a dielectric cavity filter. The cross coupling structure is arranged on a cavity wall between two adjacent resonant cavities of the dielectric cavity filter. The cross coupling structure comprises an L-shaped slot and a tuning screw; the L-shaped open slot is formed in the cavity wall and comprises a horizontal open slot and a vertical open slot which are communicated with each other and are vertically intersected; the depth of the horizontal groove is smaller than that of the vertical groove; and the tuning screw is inserted into the vertical slot along the axial direction of the vertical slot. The L-shaped slots are formed in the cavity walls of the two adjacent resonant cavities, and the depth of the tuning screws inserted into the vertical slots is adjusted, so that the cross coupling structure can be switched between inductive coupling and capacitive coupling. Meanwhile, under the determined coupling property, the frequency position of the transmission zero point can be finely adjusted by adjusting the insertion depth of the tuning screw in a small-amplitude mode.

This invention addresses the problem of effectively filtering multi-band and multi-bandwidth spectral signals by proposing a differential bandpass filter with simultaneously adjustable bandwidth and frequency band, featuring reconfigurable center frequency and bandwidth. The differential bandpass filter structure has two main parts: a resonant inverter and a parallel resonator. The programmability and reconfigurability of the differential bandpass filter are achieved by adjusting the resonant characteristics of the even / odd mode sub-circuit network of the resonant inverter. The bandwidth can be adjusted when the relative relationship between these resonators and the transmission zeros of the parallel resonator changes; when all resonant points shift while maintaining their spectral bandwidth, the center frequency is tuned to a constant absolute bandwidth. Therefore, the center frequency and bandwidth of the differential bandpass filter can be arbitrarily reconfigured and programmed within their maximum range of variation.

The application discloses a kind of broadband comb type LTCC filter transmission zero point symmetry control method, it is related to filter technical field, comprising the following steps: in the two non-adjacent resonators of comb type LTCC filter, a plane geometric symmetry cross-coupled structure is set;The cross-coupled structure has symmetry axis, and includes first adjusting part and second adjusting part symmetrically arranged about the symmetry axis;By respectively independently adjusting the geometric size of the first adjusting part, the frequency of the first transmission zero point on the low side of the filter passband is mainly controlled;The kind of broadband comb type LTCC filter transmission zero point symmetry control method is greatly simplified the three-dimensional internal structure of filter by introducing a specially designed symmetric cross-coupled structure, without increasing complex multi-path coupling network, reduces the difficulty of LTCC multilayer wiring and process implementation.

The application discloses a millimeter wave SIW filter with adjustable transmission zero point and an implementation method thereof. The filter comprises a substrate composed of an upper metal plating layer, a dielectric integrated substrate and a lower metal plating layer. An input five-fold fin line structure, a resonant cavity and an output five-fold fin line structure are sequentially arranged on the substrate. The resonant cavity is composed of a circular metalized through hole formed on the substrate. A plurality of resonant metalized through holes are further included in the resonant cavity, and the resonant metalized through holes are used for tuning the resonant cavity. The embodiment of the application provides a filter with simple structure, easy processing and flexible and controllable transmission zero point, and can be widely applied to the technical field of filters.

The utility model relates to the field of communication, and provides a low-pass structure and a filter. The low-pass structure is arranged in a low-pass cavity of the filter shell, and the low-pass cavity is provided with a first cavity wall. The low-pass structure comprises a low-pass piece, the low-pass piece comprises a high-impedance branch knot of a rod-shaped structure and at least one low-impedance branch knot, the low-impedance branch knot comprises a low-impedance part and a connecting part, the low-impedance part is located on the side, close to the first cavity wall, of the high-impedance branch knot, and the low-impedance part and the first cavity wall are spaced in an insulated mode so that capacitance can be formed between the low-impedance part and the first cavity wall. The connecting part is connected between the low-impedance part and the high-impedance branch knot. Based on the structure, the low-pass structure can generate transmission zero points with the same quantity as the low-impedance branch knots, so that the attenuation speed of out-of-band signals close to the edge of a pass band can be remarkably increased, and the near-end out-of-band rejection performance can be improved. Moreover, the low-pass structure can flexibly adjust the out-of-band rejection characteristic by increasing or decreasing the number of the low-impedance branches and flexibly adjusting the number of the generated transmission zero points, so that the design flexibility and applicability of the low-pass structure can be improved.

The invention discloses a reconfigurable filter design method applying an LC feedback technology, and the method comprises the steps: respectively determining a bandwidth parameter, a filter order, a transmission function parameter, a zero position and a topological structure for a reconfigurable high-pass filter and a reconfigurable low-pass filter; and a target tuning element used for adjusting the zero position is further selected, and the adjusting range of the target tuning element is determined, so that the passband edges and the zero positions of the high-pass and low-pass paths can be flexibly reconstructed in a preset range in a numerical control manner, and a relatively wide frequency and bandwidth reconstruction range is realized under a finite order condition. Meanwhile, according to the suppression degree index of the reconfigurable high-pass filter in the target out-of-band frequency band, an LC feedback network is introduced into the terminal unit, an additional transmission zero point is formed at a preset high-frequency position, out-of-band far-end suppression and frequency selectivity are improved, and high-frequency interference leakage is suppressed.

This invention provides an LTCC multilayer duplexer, comprising a ceramic substrate, a connection port disposed on the bottom surface of the ceramic substrate, and a circuit structure layer disposed inside the ceramic substrate. It employs a lumped parameter model design to achieve the specific electrical performance requirements of a novel, miniaturized, wideband, low-insertion-loss LTCC duplexer. The low-frequency path utilizes a second-order low-pass filter. In the high-frequency band, a bridging capacitor is introduced to create a transmission zero in the low-frequency passband, enhancing the high-frequency passband's low-frequency suppression capability. Furthermore, a higher-order approach is used to simply and effectively broaden the high-frequency passband range. This invention not only effectively achieves frequency division between low-frequency and high-frequency signals and effectively broadens the high-frequency passband bandwidth, but also possesses advantages such as miniaturization, low loss, high suppression, high isolation, high reliability, low cost, excellent consistency, and suitability for large-scale production. Additionally, it adapts to the new trend of electronic component integration and miniaturization.