41results about How to "High square factor" patented technology

The invention discloses a capacitive coupling device and a filter containing the capacitive coupling device. The capacitive coupling device comprises a dielectric body. Multiple resonance frequency tuning holes are arranged in the surface of the dielectric body. A first conductive layer is plated on the surface of the dielectric body and the resonance frequency tuning holes. A negative coupling slot is arranged in the surface of the dielectric body between two adjacent resonance frequency tuning holes. A second conductive layer is arranged in the negative coupling slot. The capacitive couplingdevice is characterized in that an insulating layer for insulating the first conductive layer and the second conductive layer is arranged on the surface of the dielectric body around the negative coupling slot. Capacitive coupling between dielectric filters is realized, the performance of filters is improved, and the size of filters is reduced. Moreover, there is no need to further limit the processing depth and width of the negative coupling slot, and the processing and manufacturing of the capacitive coupling device are facilitated.

The invention discloses a capacitive coupling device and a filter. The capacitive coupling device comprises a plurality of solid media monomers, the adjacent media units are spliced together, At leastone adjacent dielectric monome is provided with a capacitively couple structure on that splicing surface, the capacitive coupling structure includes a first blind hole and a first air coupling windowwith a surface unmetallized, The depth of the first blind hole is greater than or equal to 1 / 2 of the depth of the first air coupling window and less than the depth of the first air coupling window,a metal shielding layer is arranged on the inner wall of the first blind hole, and the first air coupling window is arranged on the two sides and the bottom of the first blind hole. Blind holes and air coupling windows are arranged on the splicing surface to realize coupling between the two cavities. The transmission zero can be formed at the low end of the pass band of the filter, and the rectangular coefficient of the filter is increased, thereby improving the filter performance and reducing the volume of the filter.

The invention discloses a specific harmonic cancellation multi-level radio frequency pulse width modulation method in which K odd number of specific harmonic waves are selected, and M-level RF-PWM signals are processed to be equivalent to N 3-level RF-PWM signals with pulse width separately controlled by corresponding comparison thresholds and stacked in a weighted manner, wherein K, M and N are all integers more than 0, N is more than K, and M is equal to 2N+1; N comparison thresholds and corresponding weighting coefficients are controlled in real time according to a normalized envelope signal SA, so that the K specific harmonic wave components of the N 3-level RF-PWM signals has stacked in a weighted manner are mutually counteracted, a base wave component is in direct proportion to the SA, and thus the K specific harmonic waves and integer multiples of odd harmonic waves of the M-level RF-PWM signals are eliminated. Based on the method, the invention also provides a specific harmoniccancellation multi-level radio frequency pulse width modulator. Compared with the prior art, the modulation method and the modulator have the beneficial effects that on the basis that the basic modulation performance is equivalent to the RF-PWM of the same level in the prior art, the suppression requirement on the filter is effectively reduced, the cost and size of the filter are reduced, and thus the comprehensive performance of the wide frequency band DTX is improved.

The invention discloses a miniaturized frequency selection surface based on a double-opening resonance ring. A band-pass effect is formed through the combined action of the double-opening resonance ring and a middle coupling aperture. When electromagnetic wave is irradiated to the frequency selection surface, resonance is caused by the opening resonance ring. The frequency selection characteristicof the opening resonance ring is utilized, so that a high spatial filtering function is achieved, meanwhile, the miniaturization characteristic is realized; compared with a common frequency selectionsurface, the cell area is greatly reduced, and the size of the whole circuit unit is only 0.3lambda 0*0.3lambda 0; meanwhile, by virtue of mutual coupling between the opening gap of the resonance ring and an interlayer coupling window, a good out-of-band rejection effect is achieved; and a transmission zero point is arranged on each of the two sides of the band, so that the rectangular coefficient of the circuit is greatly improved. A symmetrical circuit structure is adopted, so that the structure is simple, and machining is easy; and meanwhile, the whole circuit is quite high in stability around the incident angle theta and a formula which is as shown in the specification, so that the practical value is increased.

The invention provides an LC elliptic function electrically-tunable filter which relates to the field of electronic communications and aims at solving the technical problems of low rectangular factors, narrow working frequency band, complex structure, large size, and the like in the traditional electrically-tunable filter. The LC elliptic function electrically-tunable filter comprises a chip capacitor, a chip inductor, a chip resistor, a variable capacitance diode, and the like. The invention is suitable for the design of the electrically-tunable filter.

The invention provides a slot-line-form-based high-selectivity balun filter comprising a metal ground plate pasted to a lower surface of a rectangular dielectric substrate, an input port feeder line, a first output port feeder line, a second output port feeder line, a first slot line-microstrip transition structure, a second slot line-microstrip transition structure, a first E-type resonator, a second E-type resonator, a first terminal open-circuit microstrip uniform loaded resonator, and a second terminal open-circuit microstrip uniform loaded resonator. The input port feeder line, the first output port feeder line, the second output port feeder line, the first slot line-microstrip transition structure, the second slot line-microstrip transition structure, the first E-type resonator, the second E-type resonator, the first terminal open-circuit microstrip uniform loaded resonator, and the second terminal open-circuit microstrip uniform loaded resonator are pasted to the upper surface of the dielectric substrate. The balun filter based on slot line-microstrip transition structures and a dual-mode resonator with central branch loading has advantages of simple principle, high frequency selectivity, high rectangle coefficient, and wide working frequency band and is suitable for a modern wireless communication system.

The invention discloses a terahertz waveguide filter based on a dual-mode resonant cavity and a design method thereof, and belongs to the technical field of terahertz solid-state circuits. The filter comprises an input waveguide, a first diaphragm, a first resonant cavity, a second diaphragm, a second resonant cavity, a third diaphragm and an output waveguide which are arranged in sequence, by changing the relative positions of the first resonant cavity, the second resonant cavity and the adjacent diaphragms, an independent and controllable transmission zero point is introduced into an upper stop band or a lower stop band of the filter, the rectangular coefficient of the filter is greatly improved, and the filter has excellent filtering performance; the filter has a very small width-depth ratio, the overall structure is symmetrical about an E plane, the processing difficulty can be effectively reduced, the device yield is improved, and the filter is very suitable for a high-precision and low-cost numerical control milling technology; meanwhile, according to the filter design method provided by the invention, rapid design of the filter can be realized.

The invention discloses a radio frequency pulse width modulator based on digital delay line units, and a modulation unit. The modulator comprises a pulse delay control unit, a radio frequency carrierpulse production unit, the first to the fourth digital delay line units, and the first to the second two-channel multiplexers; the modulation method is as follows: the pulse delay control unit in theradio frequency pulse width modulator adopts a five-level radio frequency pulse modulation method, specifically a 3X sub-harmonic cancellation five-level radio frequency pulse modulation method, wherein X is any odd greater than zero, namely, decomposing five level radio frequency pulses needing to output into weighted stacking of two three-level radio frequency sub-pulses, and controlling the pulse widths of two three-level radio frequency sub-pulses, thereby enabling the 3X sub-harmonic amplitude to be zero after performing weighted stacking on two three-level radio frequency sub-pulses. Theactive cancellation and effective inhibition on the 3X sub-harmonic of the five-level radio frequency pulse modulation signal are realized, the cost and the volume of the filter are reduced, and thecomprehensive performance of the wide-frequency band full-digital sender is improved.

The invention discloses a design method of a high-selectivity compact band-pass filter and the filter obtained through the method. The method includes the steps that the coupling coefficient and external quality factor of a target filter are calculated through a design method of a low-pass prototype filter; the basic size of unit resonators is designed, then, multipoint simulation is conducted forthe spacing between unit resonators in a basic coupled structure to obtain the corresponding relationship of resonant frequencies and spacing points and a fitted curve, and the coupling coefficient and external quality factor corresponding to each spacing point are calculated; a group of coupling coefficient and external quality factor closest to the coupling coefficient and external quality factor obtained by the design method of the low-pass prototype filter are selected from the fitted curve to serve as the coupling coefficient and external quality factor of the target filter, the corresponding spacing value serves as the spacing between the unit resonators in the target filter, and then a final physical structure is determined. In the target filter, by introducing cross coupling to generate a pair of transmission poles, the selectivity of the filter is obviously improved.

The invention discloses a 5G communication frequency band band-pass filter based on an LTCC technology. The band-pass filter comprises a dielectric substrate, a metal isolation layer, a port unit and a filter circuit unit, wherein the dielectric substrate is a low-temperature sintered ceramic substrate and has a high dielectric constant, the metal isolation layer is composed of an upper metal silver layer and a lower metal silver layer, the port unit is a metal silver layer covering the surface of the dielectric substrate and comprises an input end, an output end and a ground end, and the filter circuit unit comprises six resonance circuits and zero coupling circuits which are arranged in parallel. The 5G communication frequency band band-pass filter is realized by adopting the HFSS three-dimensional integrated design and adopting a low-temperature co-fired ceramic technology, and has the advantages of being small in insertion loss, small in size, light in weight, high in reliability, good in temperature stability, good in electrical performance batch consistency, low in cost, capable of being produced on a large scale and the like.

The invention discloses an LC filter with a wide band, a high rectangle coefficient and a high suppression band-pass. The high suppression band-pass LC filter comprises a filter cavity, a printed circuit board, capacitors, hollow-core coils and an insulator, wherein the printed circuit board is arranged inside the cavity, the hollow-core coil is sleeved with an insulating varnish wrap of a low dielectric constant, and the capacitor and the hollow-core coil are fixed on the printed circuit board through tin soldering; the insulator is fixed inside the cavity, and one end of the insulator is welded on the printed circuit board; the LC filter is of an eight-order LC filter structure, and a topological structure of the LC filter is provided with 12 LC resonant circuit formed by the capacitors and the hollow-core coils, and each LC resonant circuit is formed by a capacitor and a hollow-core coil. The performance and the volume of the filter are taken into consideration, the LC filter has the advantages of small package, large bandwidth, low fluctuation and high stopband rejection, and meanwhile the standing wave and the insertion loss are small.

The invention discloses a capacitive coupling device and a filter. The device at least comprises a first dielectric resonator and a second dielectric resonator, a negative coupling hole is formed between the first dielectric resonator and the second dielectric resonator; the negative coupling hole comprises a longitudinal blind hole and a transverse blind groove, the longitudinal blind hole is located in the surface of a body at the connection position of the first dielectric resonator and the second dielectric resonator and is perpendicular to the surface of the body, and the transverse blindgroove is located in the body at the connection position of the first dielectric resonator and the second dielectric resonator. According to the capacitive coupling device, the longitudinal blind hole and the transverse blind groove are formed between the two dielectric resonators to form the negative coupling hole, the negative coupling between the two dielectric resonators is achieved, and thestructure is simple; the structure is used in the filter, because the area formed by two holes is larger, a transmission zero point can be formed at the low end of the passband of the filter, the rectangular coefficient of the filter is increased, the performance of the filter is improved, and the size of the filter is reduced.

The invention discloses a superconducting filter structure. The superconducting filter structure comprises an L waveband band-pass filter, a P waveband band-pass filter and an L waveband band-stop filter, which are integrated on a superconducting thin film substrate; an input end of the L waveband band-pass filter is connected with an input end of the P waveband band-pass filter, and the connection point therebetween serves as an input end of the superconducting filter structure; an output end of the L waveband band-pass filter is connected with an input of the L waveband band-stop filter, and pass bands of the L waveband band-pass filter and the L waveband band-stop filter are partially superposed; an output end of the P waveband band-pass filter is connected with an output end of the L waveband band-stop filter, and the connection point therebetween serves as an output end of the superconducting filter structure; each of the L waveband band-pass filter and the P waveband band-pass filter consists of an input feeder line, an output feeder line and a plurality of half-wavelength resonators; and the L waveband band-stop filter consists of a coupling microstrip line and a plurality of half-wavelength resonators. The superconducting filter structure can work at two frequency bands at the same time, and has a relatively high rectangle coefficient.

The invention discloses a capacitive coupling structure of a dielectric waveguide filter, relates to the field of filters, and solves the technical problem that a negative coupling hole is easy to deform after being sintered due to the fact that the negative coupling hole is too deep. The capacitive coupling structure is arranged at the midpoint of the connecting line of the debugging holes of twoadjacent resonators; the capacitive coupling structure comprises a first blind hole located in the upper surface of the dielectric waveguide filter body and a second blind hole located in the lower surface of the dielectric waveguide filter body, and the first blind hole and the second blind hole form a negative coupling hole; the sum of the depths of the first blind hole and the second blind hole is larger than the depth of the debugging hole and smaller than the distance between the upper surface and the lower surface of the dielectric waveguide filter body; and the first blind hole and thesecond blind hole are coaxially arranged. According to the invention, the rectangular coefficient, the suppression characteristic and the design flexibility of the filter are improved; and the negative coupling holes of the up-and-down symmetrical structure can enable the powder to have better fluidity during dry pressing, the density of each part of the dielectric waveguide filter body is uniform, and the problem that the negative coupling holes are easy to deform in the sintering process is avoided.

The invention discloses an FSIR-based multi-zero-point transmission characteristic filter. Multiple FSIRs form an array in a combination manner and then multi-path coupling is further formed; a puncturing hole is formed in the center of the filter, namely the center of the coupling path, to be grounded, and an electric coupler is introduced to further form electromagnetic mixed coupling; by virtueof multi-path crossed coupling and electromagnetic mixed coupling, multiple transmission zero points are realized; the high sideband suppression and wide stop band suppression performance of the filter are realized based on the multiple zero points; and meanwhile, miniaturization of the filter is realized through the FSIR. The filter has high performance advantage while the filter also can be simple in structure; batch manufacturing of the filters can be realized by adopting a simple printed circuit board process, and the processing precision can be well controlled, high rate of finished products is achieved, and the advantage of low cost can be ensured; and the filter can be applied to communication, radar and other wireless systems in a large-scale manner, such as LMDS, MMDS, 4G, 5G, marine affair radar and the like.

The invention discloses a terahertz metamaterial filter, which comprises n * n same units. Each unit is composed of multiple layers of high polymer materials including polymethacrylimide and polyimideand multiple metal layers, wherein the layers are aligned and repeatedly stacked in the sequence of metal-polyimide-polymethacrylimide from the incident direction of terahertz waves. Terahertz wavesenter the filter to generate electromagnetic resonance, the terahertz waves at the resonant frequency are reflected and absorbed to form a stop band, and waves at other frequencies are not hindered. With the filter provided by the invention, problems of small rectangular coefficient and narrow bandwidth in the existing filters of the same type are solved, and the filter has the advantages of flattop, insensitive polarization and low cost.

The invention relates to the technical field of filters, in particular to a high-selectivity suspended strip line ultra-wideband filter which comprises a metal shell body, a dielectric plate and a microstrip line structure, wherein the microstrip line structure comprises connecting units and middle units, each connecting unit comprises a high-impedance inductance microstrip and a low-impedance capacitance microstrip at least located on one side of the high-impedance inductance microstrip, each middle unit comprises a high-impedance inductance micro-strip and low-impedance capacitance micro-strips located on the two sides of the high-impedance inductance micro-strip, the two connecting units and the multiple middle units are arranged at the top and the bottom part of the dielectric plate inan up-down staggered mode, every two adjacent low-impedance capacitance micro-strips correspond to each other in the thickness direction of the dielectric plate to form a capacitance part, the connecting end of at least one connecting unit is sequentially connected with the high-impedance inductance microstrips and the low-impedance capacitance microstrips in series, and / or at least one intermediate unit is sequentially connected with the high-impedance inductance microstrips and the low-impedance capacitance microstrips in series, and a corresponding transmission zero point is generated in astop band of the filter. According to the high-selectivity suspended strip line ultra-wideband filter, the zero cavity technology is introduced for the first time, and the rectangular coefficient ofthe filter can be improved.

The invention relates to a micro-strip elliptic function band rejection filter which comprises an input SWA connector, an output SWA connector and a micro-strip elliptic function band rejection filter circuit. The micro-strip elliptic function band rejection filter circuit comprises a micro-strip main line, single-mode resonators and double-mode resonators, wherein the single-mode resonators and the double-mode resonators are arranged along the micro-strip main line at intervals. The single-mode resonators and the double-mode resonators are connected with the micro-strip main line in a coupled mode. The center frequency of the single-mode resonators is the same as that of the double-mode resonators, the interval, between the single-mode resonators and the double-mode resonators, of the micro-strip main line is 1 / 4 wavelength. The double-mode resonators are each composed of two resonance units which are coupled to each other, wherein both the two resonance units are single-mode resonators of 1 / 2 wavelength, and the resonance frequency of the two resonance units are located at the two sides of the center frequency respectively. By means of the technical scheme, the micro-strip elliptic function band rejection filter has the elliptic function transmission feature and has the advantages of being deep in notch suppression, high in rectangle coefficient, low in passband insertion loss and the like.

The application relates to a low-pass filter comprising a body, a capacitor, and an inductor. The body comprises a grounding electrode, a capacitor layer and an inductor layer which are stacked in sequence; the capacitor layer comprises stacked first dielectric substrates; and the inductor layer comprises stacked second dielectric substrates. The capacitor comprises a first polar plate and a second polar plate which are arranged in an interdigital manner; the first polar plate and the second polar plate are respectively formed on different first dielectric substrates; and the first polar plateis electrically connected with the grounding electrode through at least two metal through holes. The inductor comprises at least two annular conductors; the annular conductors are respectively formedon different second dielectric substrates and are electrically connected in sequence through the metal through holes; any annular conductor is electrically connected with the second polar plate, so that Q values and self-resonant frequency points of the capacitor and the inductor can be improved, the insertion loss of the low-pass filter is reduced, the rectangular coefficient of the filter is improved, and the filtering effect is improved.

The invention discloses a capacitive coupling device and a filter. The capacitive coupling device comprises a first dielectric resonator and a second dielectric resonator which are connected with eachother, wherein a negative coupling hole is formed between the first dielectric resonator and the second dielectric resonator, the negative coupling hole comprises a longitudinal blind hole and a transverse blind hole, the longitudinal blind hole and the transverse blind hole are perpendicular to each other, the longitudinal blind hole is perpendicular to the top surfaces of the first dielectric resonator and the second dielectric resonator, and the transverse blind hole is perpendicular to the side surfaces of the first dielectric resonator and the second dielectric resonator. According to the capacitive coupling device, the two blind holes which are perpendicular to each other are formed between the two dielectric resonators to form the negative coupling hole, negative coupling between the two dielectric resonators is achieved, and the structure is simple. The structure is used in the filter, due to the fact that the area formed by the two holes is larger, a transmission zero point can be formed at the low end of a passband of the filter, the rectangular coefficient of the filter is increased, the performance of the filter is improved, and the size of the filter is reduced.

The invention discloses a 5G communication frequency band pass filter based on LTCC technology. The band pass filter includes a dielectric substrate, a metal isolation layer, a port unit, and a filter circuit unit, wherein the dielectric substrate is a low-temperature sintered ceramic substrate, which has relatively High dielectric constant, the metal isolation layer is composed of the upper and lower layers of the metal silver layer with vacancies dug, the port unit is the metal silver layer covering the surface of the dielectric substrate, including the input end, output end and ground end, the filter circuit unit includes Six resonant circuits and zero-point coupling circuits arranged in parallel. The present invention adopts HFSS three-dimensional integrated design, adopts low-temperature co-fired ceramic technology to realize, and has the advantages of small insertion loss, small volume, light weight, high reliability, good temperature stability, good batch consistency of electrical properties, low cost, and large capacity. Mass production and other advantages.

The invention discloses a terahertz metamaterial filter comprising: n×n identical units; each unit is composed of multi-layer polymer materials polymethacrylimide and polyimide and multi-layer metal layers, And starting from the incident direction of the terahertz wave, they are aligned and stacked repeatedly in the order of metal-polyimide-polymethacrylimide. The terahertz wave is incident on the filter to generate electromagnetic resonance, the terahertz wave at the resonant frequency is reflected and absorbed to form a stop band, and the waves of other frequencies are not hindered. The filter of the present invention mainly solves the problems of small square coefficient and narrow bandwidth in the existing filters of the same type, and has the advantages of flat top, polarization insensitivity and low cost.

A multi-level radio frequency pulse width modulation method for specific harmonic elimination, selects K odd specific harmonics, and converts M-level RF-PWM signals into N pulse widths controlled by corresponding comparison thresholds. RF-PWM signal weighted superposition, K, M, N are all integers greater than zero and N>K, M=2N+1, according to the normalized envelope signal S A Real-time control of N comparison thresholds and corresponding weighting coefficients, so that K specific harmonic components of N 3-level RF-PWM signals after weighted superimposition cancel each other out, and its fundamental component and S A proportional to the K specific harmonics of the M-level RF-PWM signal and its integer multiple odd harmonics. Based on the above method, the present invention also provides a multi-level radio frequency pulse width modulator for specific harmonic elimination. Compared with the prior art, the beneficial effects of the present invention are: on the basis that the basic modulation performance is equivalent to that of the same level RF-PWM of the prior art, the suppression requirement for the filter is effectively reduced, the cost and volume of the filter are reduced, thereby improving the broadband DT X comprehensive performance.

The invention discloses a waveguide filter based on electromagnetically induced transparency. The waveguide filter comprises an upper cavity, a lower cavity, a medium substrate, a signal input port and a signal output port, wherein the upper cavity and the lower cavity form a standard rectangular waveguide, and the medium substrate is inserted into the portion between the upper cavity and the lower cavity of the standard rectangular waveguide. A rectangular metal ring, an out-of-band rejection sheet, two rows of metallized through holes and a grounding epitaxial band are arranged in a metal micro-strip structure on the front face of the medium substrate, and two symmetric C-shaped resonance structures and a grounding epitaxial band are arranged on a metal micro-strip structure on the back face of the medium substrate. The rectangular metal ring located on the front side of the medium substrate and the two symmetric C-shaped resonance structures located on the back face of the medium substrate interact to generate a passing band of an electrically induced transparent window and a passing band of a magnetically induced transparent window, namely, the electromagnetically induced transparency effect is formed, upper sidebands and lower sidebands of the passing bands of the waveguide filter obtained through the effect are respectively provided with a transmission zero, high selectivity is achieved, and the waveguide filter is compact in structure and easy to design.

The invention discloses a double-zero notch dual-polarized antenna for a WLAN. The antenna comprises a dielectric substrate, an upper metal layer and a lower metal layer, the upper metal layer and thelower metal layer are respectively printed on the upper surface and the lower surface of the dielectric substrate, and the upper metal layer and the lower metal layer are respectively printed with two pairs of dipole antennas in cross distribution. Coplanar waveguide notch structures are arranged in antenna arms of the dipole antennas, and the notch structures are double-U-shaped broken lines etched on upper metal layer feeder lines. The double-U-shaped broken line notch structure has the characteristic of miniaturization, an inner ring of a dipole antenna with a small area is convenient to embed, and a notch function is introduced under the condition that the size of the antenna is not increased; a double-zero trapped wave structure formed by the trapped wave structures and an opening outer ring enables the antenna to obtain a double-zero trapped wave function, the stop band is wide, and the rectangular coefficient is high; an extra filter circuit is not needed, so that the antenna is small in size and simple in structure.

The invention discloses a cascade refractive index sensor based on a layered stacking structure coated with an anti-reflection coating. The cascade refractive index sensor comprises a signal transmitter, a magnetic field generator, an angle control rotating table, a coupler, the layered stacking structure, a micro motor, a spectrum analyzer and a carrying platform, wherein the signal transmitter, the magnetic field generator, the angle control rotating table, the coupler and the spectrum analyzer are electrically connected with the micro motor; the angle control rotating table is further connected with the layered stacking structure; the coupler is also connected with the layered stacking structure and the spectrum analyzer; the layered stacking structure comprises a main body structure and an anti-reflection coating; the main body structure comprises a medium A1 and an InSb1 medium which are arranged in sequence; and the anti-reflection coating comprises a medium InSb2, a medium A1 and a medium A2 which are arranged in sequence. Cascade measurement of different refractive index ranges can be realized by regulating and controlling the magnetic field intensity. The sensor has the characteristics of novel design, large measurement range, high sensitivity, cascade functions and the like.

The invention discloses a high-performance filter integrating combination of a passive device and an acoustic mechanical wave device, and relates to the technical field of filters, the high-performance filter comprises a substrate, an FBAR device and an IPD device, the FBAR device comprises a cap layer and an RDL layer, the FBAR device and the IPD device are integrated and assembled on the substrate, and the cap layer and the RDL layer are arranged on the substrate. The integration mode of the FBAR device and the IPD device comprises one of the modes that partial wiring and inductance wiring are concentrated in a cap layer and an RDL layer of the FBAR device or the IPD device is integrated in the cap layer of the FBAR device. According to the invention, the cascade stage number of the FBAR can be greatly reduced, the size of the FABR device is reduced, and the overall heat dissipation effect is relatively improved (the power capacity is improved) and the suppression of parasitic harmonics is enhanced in combination with the IPD device. Products with different frequency bands, different bandwidths, low insertion loss, high rectangular coefficient, high power and high harmonic suppression can be flexibly realized, and the device is suitable for popularization and application.

The invention discloses a miniaturized frequency selection surface based on a double-opening resonance ring. A band-pass effect is formed through the combined action of the double-opening resonance ring and a middle coupling aperture. When electromagnetic wave is irradiated to the frequency selection surface, resonance is caused by the opening resonance ring. The frequency selection characteristicof the opening resonance ring is utilized, so that a high spatial filtering function is achieved, meanwhile, the miniaturization characteristic is realized; compared with a common frequency selectionsurface, the cell area is greatly reduced, and the size of the whole circuit unit is only 0.3lambda 0*0.3lambda 0; meanwhile, by virtue of mutual coupling between the opening gap of the resonance ring and an interlayer coupling window, a good out-of-band rejection effect is achieved; and a transmission zero point is arranged on each of the two sides of the band, so that the rectangular coefficient of the circuit is greatly improved. A symmetrical circuit structure is adopted, so that the structure is simple, and machining is easy; and meanwhile, the whole circuit is quite high in stability around the incident angle theta and a formula which is as shown in the specification, so that the practical value is increased.