90 results about "Split-ring resonator" patented technology

The invention belongs to the technical field of antennas, and particularly relates to an ultrathin full-space metasurface unit with dual-band amplitude-phase regulation and control and a multi-beam generator. In order to solve the problems that component design cost is high, unit amplitude is low, and incident wave energy cannot be efficiently regulated and controlled, the full-space metasurface unit comprises a first metal layer and a second metal layer, the first metal layer is located above the second metal layer, a dielectric plate is arranged between the first metal layer and the second metal layer, and the dielectric plate is located between the first metal layer and the second metal layer. A first C-shaped groove and a double split ring resonator are etched on the first metal layer from outside to inside in a hollowed-out manner, a second C-shaped groove and an elliptical groove are etched on the second metal layer from outside to inside in a hollowed-out manner, and the opening directions of the first C-shaped groove and the second C-shaped groove are perpendicular to each other. And the multi-beam generator is designed based on the total space metasurface unit.

The invention discloses a double-frequency phase independent regulation and control metasurface unit and an application method. The metasurface unit comprises a dielectric substrate; the two sides of the dielectric substrate are covered with a first metal layer and a second metal layer respectively. Each of the first metal layer and the second metal layer comprises a metal patch main body and a phase regulation and control structure, the center of the metal patch main body is provided with a circular hollow, and the phase regulation and control structure is arranged in the circular hollow; the phase regulation and control structure of the first metal layer and the phase regulation and control structure of the second metal layer are in 180-degree rotational symmetry; the double-connecting-ring structure is an axisymmetric structure; an open circular split ring resonator is arranged in the double-connecting-ring structure, and an electromagnetic isolating ring group is arranged in the open circular split ring resonator; according to the invention, 360-degree independent phase control on electromagnetic waves at a low-frequency band and a high-frequency band is realized.

An ESA antenna includes a layer of filters between the layer of radiating elements and the ground layer. The filter layer obviates certain post processing steps. The filters define a passband at the operating range of the antenna and a stopband defined to prevent crosstalk or reduce known external interference. Each filter includes alternating cells of a resonator cell formed by two split ring resonators and a resonator cell formed by a complementary split ring resonator and a complementary patch / stub. A particular implementation of the filter defines an operating range around 23 gigahertz with a passband to stopband transition of less than 500 megahertz. Vias may connect the filter layer to a surface component layer with beamforming integrated circuits, bypassing the routing layer.

The invention relates to a high-sensitivity differential microfluid sensor based on a microstrip line, which is used for measuring the concentration of a water-ethanol mixed solution, and comprises the microstrip line configured with a symmetrical shunt / combiner, a pair of split ring resonators with bent grooves, and a microfluid channel, a dielectric layer and a metal ground which are arranged at the tops of the split ring resonators from the top layer to the bottom layer. Wherein the bent groove parts of the two SRRs are areas with the maximum electric field intensity, and a micro-fluidic channel made of polydimethylsiloxane (PDMS) is placed in the areas. A sensor parameter curve is measured by a vector network analyzer (VNA). The suggested size of the sensor is 30 * 20 mm < 2 >, and the working frequency is 4.8 GHz. Experimental results show that the resonant frequency of the water-ethanol mixture with the concentration range of 0-100% has linear shift of 1250 MHz, and the average sensitivity Savf of detection is 0.987%. The sensor has the characteristics of compactness, high sensitivity, high measurement precision, no environmental interference and the like, and has wide application prospects in the fields of biomedical detection, material analysis, environmental monitoring and the like.

The invention discloses a band-pass filter based on an artificial surface plasmon polariton structure and a design method thereof, a metal structure of the band-pass filter comprises an polariton structure region, the polariton structure region is provided with a plurality of plasmon polariton grooves, and the plurality of plasmon polariton grooves are arranged at intervals along a first direction; the depth direction of the plasmon polariton grooves is perpendicular to the first direction, the lengths and the widths of the plasmon polariton grooves are the same, and the multiple plasmon polariton grooves are formed in the same side of the polariton structure; the split resonant rings are arranged on the dielectric substrate, and the multiple split resonant rings are arranged close to the metal structure. Due to the fact that the multiple plasmon polariton grooves formed in the polariton structure and arranged at intervals in the first direction can form the artificial surface plasmon polariton structure, the band-pass filter based on the artificial surface plasmon polariton structure has the high inhibition capacity for harmonic waves of the band-pass frequency, and the band-pass filter based on the artificial surface plasmon polariton structure has the good inhibition capacity for the harmonic waves of the band-pass frequency.

The invention relates to the technical field of antennas, and discloses a folding Cassegrain antenna, a polarization flipping focusing metasurface is located below a frequency-polarization adjustable metasurface, and the distance between the polarization flipping focusing metasurface and the frequency-polarization adjustable metasurface is half of the focal length of the polarization flipping focusing metasurface; the linear polarization feed source is located at the focus of the polarization overturning focusing metasurface and used for radiating y polarization waves; the frequency-polarization adjustable metasurface comprises a plurality of polarization rotation units which are arranged periodically, and each polarization rotation unit comprises a flexible substrate located on the upper layer, two single-opening resonance rings which are etched on the flexible substrate and are opposite in opening direction, and a metal grating located on the lower layer. By folding the flexible substrate, the polarization rotation unit forms a left-handed or right-handed chiral structure, and the technical effects of reconfigurable switching of x-polarized waves, left-handed circularly-polarized waves and right-handed circularly-polarized waves and adjustable central working frequency of the folding Cassegrain antenna can be achieved.

The invention relates to an electromagnetic sensor based on a split-ring resonator array and a crack detection method, the sensor comprises a first flexible dielectric substrate, a bonding layer, a second flexible dielectric substrate and a metal grounding layer which are bonded from top to bottom, and the top surface of the first flexible dielectric substrate is provided with a microstrip transmission line; one end of the first flexible dielectric substrate is provided with an SMA interface hole, and the bottom surface of the first flexible dielectric substrate is provided with a split-ring resonator array which is in electromagnetic coupling with the microstrip transmission line. The invention also provides a crack detection method of the sensor. The electromagnetic sensor is adjustable in detection area and uniform in field distribution.

An antenna device comprises a case and an antenna element. The antenna element is arranged in the case and radiates a radio wave with a predetermined frequency which has a plane of polarization in parallel to a predetermined plane. The case is formed with a predetermined opening. The predetermined opening has two main openings and a coupling opening. The two main openings are apart from each other in a first direction perpendicular to the predetermined plane. The coupling opening couples the two main openings together in the first direction. The coupling opening has a size smaller than another size of each of the two main openings in a second direction perpendicular to the first direction. The predetermined opening forms a split ring resonator which resonates at the predetermined frequency and radiates a radio wave corresponding to the radio wave radiated from the antenna element.

The application provides a controllable attenuator based on a complementary open resonant ring structure, which is composed of a cascaded active gain compensation amplifier and an open resonant low-pass filter. The open resonant low-pass filter comprises a microstrip low-pass filter, a complementary open resonant ring, a variable capacitor and a control circuit. The microstrip low-pass filter is composed of a middle dielectric layer and a first metal surface and a second metal surface located on both sides of the dielectric layer. The complementary open resonant ring is designed on the second metal surface. The variable capacitor is connected in parallel between the inner metal surface and the outer metal surface of the complementary open resonant ring. The capacitance of the variable capacitor is adjusted through the control circuit, so as to control the attenuation amplitude of the controllable attenuator based on the complementary open resonant ring structure. The controllable attenuator based on the complementary open resonant ring structure has a very small volume and can be integrated into a chip.

The present invention discloses a broadband magnetoelectric dipole antenna with second harmonic suppression. The antenna comprises: an antenna feed structure comprising a bottom dielectric substrate, a rod-shaped stripline, and an H-shaped slot. The bottom dielectric substrate is provided with an upper floor and a lower floor, respectively, on both surfaces thereof. The H-shaped slot is etched into the upper floor, and the rod-shaped stripline is disposed within the bottom dielectric substrate. An antenna radiator structure comprises a top dielectric substrate, a main patch disposed on the top surface of the top dielectric substrate, and the main patch is connected to the upper floor via a grounded metal post. An antenna filter structure comprises an open resonant ring, a grounded metal branch, and a feeder branch. The open resonant ring is printed on the top surface of the top dielectric substrate. The grounded metal branch is located within the top dielectric substrate and connected to the upper floor. The feeder branch is printed on the top surface of the bottom dielectric substrate and connected to the rod-shaped stripline. This antenna can achieve second harmonic suppression without increasing the antenna volume and without affecting in-band matching.

The application discloses a kind of based on double-sided spiral wiring and low profile ultra-wideband antenna device of lossy open resonant ring loading, including double-sided spiral antenna structure, lossy open resonant ring structure, metal back cavity and balun, wherein the upper and lower surfaces of double-sided spiral antenna structure are respectively provided with Archimedes spiral arm, and are provided with the metal via hole that is connected with different levels spiral arm;The lossy open resonant ring structure is provided with annular dielectric substrate, and a circle of open resonant ring loaded with resistance is arranged on the upper surface thereof;Double-sided spiral antenna structure is located above the lossy open resonant ring structure, and both are arranged in the metal back cavity;Balun is vertically arranged in the center of metal back cavity, and the top end is respectively connected with the two spiral arms on the upper surface of circular dielectric substrate, and the bottom end is arranged on the bottom surface of metal back cavity and connected with external antenna interface through through-hole.The antenna device with improved structure has ultra-wideband, low profile, high gain, unidirectional radiation and good circular polarization characteristics.

The invention provides a passive broadband non-reciprocal electromagnetic wave absorber and a manufacturing method, and the passive broadband non-reciprocal electromagnetic wave absorber comprises three layers of structures from bottom to top: a bottom layer metal reflection backboard, a ferrite substrate and a metal complementary split ring resonator (CSRR) array. Wherein the bottom metal reflection back plate, the ferrite substrate and the CSRR array are square plate-shaped structures with the same shape, and the ferrite substrate is arranged between the bottom metal reflection back plate and the CSRR array; the ferrite substrate is made of La-doped BaFe12O9, and has an asymmetric magnetic conductivity tensor characteristic; the surface layer of the CSRR array is provided with a metal complementary opening; and the CSRR array is coupled with the non-reciprocal characteristic of the ferrite substrate to form differential absorption of left-hand circularly polarized waves and right-hand circularly polarized waves.

This invention relates to a high-focusing-efficiency planar metal metasurface lens, belonging to the field of microwave lenses. It comprises a dielectric layer, a metal layer, and an aperture ring. Two metal layers cover the two end faces of the dielectric layer. Several aperture rings are spaced apart on the metal layers. The aperture rings are two sets of concentric segmented circular rings with symmetrical double openings, distributed internally and externally. The opening portion of the inner ring is deflected by an angle greater than 0° along the center, causing the segmented circular rings within the aperture ring to be asymmetrically distributed, thereby achieving a focusing efficiency greater than 60% and a magnification of 16 times. This invention has the advantages of achieving high focusing efficiency and high magnification by employing an ultra-thin double-layer metal twisted double-aperture resonant ring metasurface unit and a single dielectric interlayer structure.

The invention discloses a dual-polarization microwave energy efficient receiving composite metasurface array and a receiving method, and the method comprises the steps: enabling different polarization plane waves to irradiate a polarization selective waveform conversion function region composed of biaxial symmetric split-ring resonators, and carrying out the unit differential response and reflection phase gradient arrangement, converting the x-polarized plane wave and the y-polarized plane wave into surface waves propagating in the-x direction and the y direction respectively; the square ring-shaped artificial surface plasmon polariton structure is used for receiving the surface wave, and the surface wave is stably guided to the waveform focusing and energy extraction functional area through momentum matching; by means of gradient refractive index distribution focusing surface waves of a planar semi-Maxwell fisheye lens, an equiphase surface is bent into a spherical surface shape, and energy is converged to a focus; energy is led out through the microstrip line structure at the focus, efficient transmission is achieved through impedance matching, and collection and conversion of different polarization microwave energy are completed. The polarization sensitivity problem of a traditional scheme is solved, and the microwave energy collection efficiency is improved.

The application discloses a manufacturing method of a graphene back gate electrode terahertz wave modulator, which comprises the following steps: growing and transferring a first layer of graphene; photoetching a graphene back gate pattern; photoetching a back gate electrode pattern and preparing a back gate electrode; growing a medium layer; growing and transferring a second layer of graphene; photoetching a graphene strip pattern and preparing a graphene strip; photoetching an open resonant ring pattern and preparing an open resonant ring metal. The application discloses a terahertz wave modulator, which comprises a high-resistance substrate, a graphene back gate electrode layer and a high-K gate medium layer which are sequentially bonded from bottom to top; the high-K gate medium layer is provided with an array of graphene strips and an open resonant ring metal, the open resonant ring metal is arranged around the graphene strips and is in physical contact with the graphene strips. The application constructs a back gate electrode on a single layer of graphene, thereby getting rid of the absorption of a conductive substrate to terahertz waves and effectively improving the modulation efficiency of the terahertz wave modulator to terahertz waves.

The application discloses a kind of microwave metamaterial high-temperature sensors based on planar waveguide and preparation method thereof, it is related to sensor technical field.The sensor includes: by top to bottom sequentially arranged top metal layer, dielectric substrate and bottom metal layer;Top metal layer integrates single square complementary split ring resonator structure and periodic arrangement of annular complementary split ring resonator structure;Square complementary split ring resonator structure is located at the center position of top metal layer;Annular complementary split ring resonator structure is located at the two sides of top metal layer, and the opening direction in two sides annular complementary split ring resonator structure is opposite.Wherein, dielectric substrate, top metal layer, bottom metal layer and annular complementary split ring resonator structure form planar waveguide, square complementary split ring resonator structure forms resonant loop and carries out wireless signal transmission, the present application can realize wireless passive, real-time in situ, high-quality factor of harsh environment superhigh temperature monitoring.

This device comprises a substrate (101), fine particles (102) dispersed in the substrate (101), and a circuit (103) formed on the surface of the substrate (101). The substrate (101) is composed of a hydrogel which is composed of a hydrophilic material that is edible, and which solates at body temperature. The circuit (103) is, for example, a resonance circuit such as an LCR resonance circuit or a split ring resonator. The circuit (103) can be composed of an electroconductive material that is edible.

This invention discloses a structure and method for achieving wide-bandwidth beam characteristics based on an open-circuit resonator, solving the problems of wide-bandwidth angular domain, compact structure, and low cost compatibility in radar detection. The parasitic structure proposed in this invention is an open-circuit resonator array, composed of stacked subarrays of different frequency bands that are interconnected and cover the antenna's frequency band. The method includes designing the parasitic structure; stacking and assembling the arrays according to the number and frequency bands of the antenna stator arrays; combining the parasitic structure with the antenna; and achieving wide-bandwidth beam characteristics. This invention utilizes the omnidirectional radiation characteristics of the open-circuit resonator to form an array, extending the antenna's beamwidth over a wide range. The open-circuit resonator unit is relatively small, and this invention achieves beam extension functionality within a compact space, exhibiting miniaturization characteristics, and can be applied to small computers and UAVs. This invention prints the open-circuit resonator on the surface of a dielectric substrate, allowing for integrated design with the antenna, significantly reducing design, manufacturing, and installation costs.

The invention relates to the field of metamaterial antennas, and provides a directional radiation antenna structure with adjustable power, which aims at solving the problem that the existing beam control or directional diagram reconstruction method generally depends on a mechanical system, a phased array or a reconfigurable metasurface and lacks the capability of dynamically and continuously adjusting the radiation power of a directional antenna on the premise of not changing the beam shape. One end of the metal waveguide A fixes the SMA connector, and the other end is connected with the metal waveguide B; the metal waveguide B is of a cavity structure, an electric regulation and control structure is arranged in an inner cavity of the metal waveguide B. A plurality of openings distributed at equal intervals are formed in the outer side of the emergent face of the metal waveguide C. The resonance characteristic of the electric opening resonance ring is changed by changing capacitance of the variable capacitance diode. The metamaterial antenna with the near-zero dielectric constant can keep high directionality and a stable radiation pattern, and the radiation power of the metamaterial antenna with the near-zero dielectric constant can be remarkably enhanced.

The application discloses application of an active double-mode microwave micro-flow sensor to liquid dielectric constant detection. The double-mode resonant unit is formed by a microstrip line and a split ring resonator, and has high and low resonant frequency points. The low-frequency resonant frequency point moves to a low frequency with the increase of the dielectric constant, and the high-frequency frequency point moves to a high frequency with the increase of the dielectric constant, thereby effectively increasing the sensitivity of the passive resonant unit. A negative impedance circuit is embedded at the rear end of the microwave passive sensor to form an oscillator, namely a microwave passive resonator and a radio frequency amplifier, and the oscillation frequency changes with the change of the dielectric constant of the material to be detected, and the change of the dielectric constant is mapped to the change of the oscillation frequency. The relationship between the dielectric constant and the resonant frequency is converted to the relationship between the dielectric constant and the direct current voltage through a demodulation circuit. The application has the advantages of high sensitivity, low price, convenience for carrying, etc., and is a high-performance and low-cost system-level detection device which will play an important role in the detection field of liquid materials.

The invention belongs to the technical field of terahertz modulators and millimeter wave communication, and provides a high-power terahertz modulator based on gallium nitride Schottky. According to the invention, the dynamic switching of the resonant mode of the resonant micro-unit is realized by using the switching characteristic of the GaN Schottky diode under forward / reverse bias; when the diode is positively biased, the diode is conducted, so that the resonance micro unit is in a closed loop resonance state, and terahertz wave conduction is realized; when the diode is in zero / reverse bias, the resonance micro-unit is in a double-opening resonance state, the modulator is in a turn-off state, the diode is in the turn-off state at the moment, and the thermal runaway risk of the diode in the on state is effectively restrained. Meanwhile, by transversely expanding the metal areas on the two sides of the gap of the double-gap rectangular opening resonant ring, the electric field distribution space is expanded, the peak field intensity is reduced, and the power bearing capacity of the diode is improved; finally, collaborative improvement of the modulator in the aspects of high power tolerance, high speed, low insertion loss and the like is realized.

The application discloses a micro substrate integrated waveguide filter with in-band ripple suppression, a wide-stop-band band-pass filter adopts a single-cavity substrate integrated waveguide structure, four novel complementary open-loop resonant rings with the same shape are etched on the upper layer metal of the resonant cavity and are recorded as wide-stop-band resonant rings, a capacitive slot line is etched on the middle position of the upper layer metal along the longitudinal direction and is recorded as a wide-stop-band capacitive slot line, and the lower layer metal is etched to form a defect ground; a dual-band band-pass filter adopts a single-cavity substrate integrated waveguide structure, four novel complementary open-loop resonant rings are etched on the upper layer metal of the resonant cavity, the four open-loop resonant rings are divided into two groups according to the size and are recorded as large resonant rings and small resonant rings, a capacitive slot line is etched on the middle position of the upper layer metal along the longitudinal direction and is recorded as a dual-band capacitive slot line, a grid-shaped slot line is etched along the transverse direction, a symmetrical slot microstrip line is etched at the tapered interface of the upper layer metal, a metal counterbore is arranged in the resonant cavity, and a slow-wave substrate integrated waveguide structure is formed by connecting a circuit ground plane.

The invention provides an intracranial pressure sensor based on a split-ring resonator structure, a monitoring system and a monitoring method, and belongs to the technical field of medical instruments. The intracranial pressure sensor is composed of a substrate, an interdigital capacitor-split resonant ring structure and a micro-channel pressure conversion structure. Intracranial pressure acts on the micro-channel film to drive the gallium-indium eutectic alloy to displace, the interdigital capacitance is modulated in real time, resonant frequency deviation is caused, and 0.47 MHz / kPa high-sensitivity pressure monitoring is achieved. The monitoring system comprises an intracranial pressure sensor, an in-vitro radio frequency read-write device and a data processing terminal, and the intracranial pressure can be continuously monitored in real time for a long time. Compared with an existing intracranial pressure detection means, the intracranial pressure sensor based on the split-ring resonator structure, the monitoring system and the monitoring method have the advantages that high sensitivity, high stability, good repeatability and excellent wireless readability are achieved on the basis that an integrated chip is not needed, and a better solution is provided for high-precision minimally invasive intracranial pressure monitoring.

The application discloses a transmissive array antenna with high selective gain filtering characteristics, which comprises a planar transmissive array as a transmissive surface and a horn antenna as a feed source; a 180-degree transmissive phase difference is realized by rotating a feed part of a magnetic electric dipole of the planar transmissive array by 0 degree or 180 degrees around a central axis; the planar transmissive array comprises a plurality of periodically and seamlessly distributed transmissive units, each of which generates a different compensation phase when subjected to a y-polarized incident wave, so as to form a required beam direction; the method is based on a magnetic electric dipole antenna loaded with split ring resonators, can realize higher selectivity under a planar structure, avoids the design of a complex filter part and a higher profile of a three-dimensional structure in an antenna-filter-antenna structure, can be widely applied to long-distance communication, and can more fully utilize limited electromagnetic spectrum.

The utility model relates to the field of multi-frequency monopole antennas, and particularly discloses a multi-frequency monopole antenna loaded with an asymmetric metamaterial unit, which comprises a monopole antenna unit and a branch knot formed by a grounding plate and at least two radiation patches and used for generating resonance in a specific frequency band; the asymmetric metamaterial unit comprises split-ring resonator structures and closed-ring resonator structures, the split-ring resonator structures and the closed-ring resonator structures are arranged at the bottom of the monopole antenna unit at certain intervals, and the split-ring resonator structures and the closed-ring resonator structures do not form a symmetric relationship; by combining the monopole antenna unit and the asymmetric metamaterial unit, the antenna can generate resonance in a plurality of frequency bands, such as 2.4 GHz, 3.5 GHz and 5.8 GHz, so that the antenna can be widely applied to a plurality of communication systems through the multi-frequency working capability, and the requirements of different frequency bands are met; through the introduction of the asymmetric metamaterial unit, the performance indexes such as gain, directivity and efficiency of the antenna are improved, so that the overall performance of a communication system is improved.

The application relates to the field of super surfaces and relates to a microwave band loss type super surface lens for observing chiral singular points. The application is aimed at solving the problem of difficulty in forming a plasmonic surface in a microwave band and introducing loss. The microwave band loss type super surface lens for observing chiral singular points comprises a plurality of double-resonance loop units arranged in a rectangular array, each double-resonance loop unit comprising a dielectric plate, an open resonant loop and a line structure; the open resonant loop comprises three coaxially nested rectangular loops and a rectangular sheet located at the center of the innermost rectangular loop, and one side of the outermost rectangular loop is provided with an opening; the line structure is in the shape of an I letter; the open resonant loop and the line structure are fixed on the dielectric plate, and a gap is left between the two. The application can realize the observation of X-band singular points by coupling resonance modes in two orthogonal directions and introducing loss without forming a plasmonic surface.

The invention discloses a total-space holographic imaging method based on Janus metasurface amplitude-phase independent control, a basic unit of a metasurface is formed by alternately stacking three metal layers and two dielectric substrates, and transmission-reflection independent regulation and control and direction selective response of dual-frequency (9.5 GHz and 16GHz) and dual-polarization incident electromagnetic waves are achieved. According to the invention, by adjusting the rotation angle and the field angle of the slit of the split-ring resonator in the transmission structure and the rotation angle and the field angle of the I-shaped slit in the reflection structure, the full-range independent regulation and control of the amplitude (0-1) and the phase (0-2pi) of the transmission channel and the reflection channel can be respectively realized; four preset high-quality holographic images can be generated under different incident directions, frequencies and polarization conditions. The metasurface has the advantages of being compact in structure, high in function integration degree and rich in encryption dimension, and can be applied to the fields of information encryption, high-quality imaging, data storage and the like.

The application discloses a graphene optical modulator based on hybrid surface plasmons, which comprises, from top to bottom, an open-like resonant ring strip-shaped waveguide, a graphene layer, a dielectric spacer layer, a substrate and a bottom electrode, and one gate voltage electrode is arranged on each side of the open-like resonant ring strip-shaped waveguide; the cross section of the open-like resonant ring strip-shaped waveguide is in an open-like resonant ring structure; the open end of the open-like resonant ring structure is in contact with the graphene layer; the dielectric spacer layer has a thickness of 5-50 nm; the two gate voltage electrodes are respectively a source electrode and a drain electrode, and the bottom electrode is a gate electrode, and the incident light is modulated by controlling the voltage of the source electrode, the drain electrode and the gate electrode; the input light to be modulated is incident perpendicularly to the cross section, and the hybrid surface plasmons are excited at the open end surface of the open-like resonant ring strip-shaped waveguide and the interface between the dielectric spacer layer and the graphene layer close to each other. The application improves the on-off ratio, bandwidth and various modulation performances of the modulator based on the graphene material.

The invention discloses a microstrip band-stop filter with a wide upper passband, and relates to the technical field of radio frequency passive devices, and the microstrip band-stop filter comprises an electromagnetic shielding cavity, a dielectric substrate, a microstrip circuit located on the front surface of the dielectric substrate, and a grounding metal layer located on the back surface of the dielectric substrate. The microstrip circuit is composed of an input feeder line, an output feeder line and a four-stage cascade filter network located between the input feeder line and the output feeder line. The stopband center frequencies of the four filtering units are distributed in a staggered manner so as to broaden the stopband bandwidth; each filtering unit is composed of two U-shaped micro-strips and an interdigital capacitor, and symmetrical rectangular split ring resonators loaded with the interdigital capacitors and double-path arc-shaped parallel micro-strip lines are adopted at the interstage connecting positions of the filtering units respectively. According to the invention, the low insertion loss, high selectivity and miniaturization design of the filter are realized, and the technical problem that the existing band elimination filter is difficult to adapt to a complex and changeable signal environment due to the limited passband width is solved.

The invention discloses a resonant ring multilayer medium probe and method for detecting defects of a metal outer surface wave-absorbing material, and belongs to the technical field of microwave detection. In order to solve the problem that there is no resonant multilayer dielectric structure probe capable of detecting the defects of a non-metal wave-absorbing material on the surface of a metal layer at present, the probe is of a multilayer plane printing structure and comprises a feeder line, a lower dielectric substrate, a grounding plate, an upper dielectric substrate and a radiation metal patch from bottom to top, the radiation metal patch, the grounding plate and the feeder line are metal layers, the center of the grounding plate is provided with a rectangular gap, the lower side of the lower dielectric plate is printed with a microstrip line for feeding, the radiation metal patch is composed of a plurality of rectangular resonant rings which are symmetrically arranged according to a matrix structure, each rectangular resonant ring is composed of an outer ring and an inner ring, and a gap is arranged between the outer ring and the inner ring. The outer ring and the inner ring are both provided with openings, and the resonant ring is printed on the upper dielectric substrate. During detection, damage detection of the wave-absorbing coating on the outer surface of the metal is realized by using an S11 curve corresponding to the probe.