222 results about "Electrical length" patented technology

The broadband low-profile dual-polarization omnidirectional antenna comprises a horizontal polarization radiator, a metal coupling patch, a vertical polarization radiator and a metal floor which are sequentially arranged from top to bottom, the horizontal polarization radiator comprises a dielectric substrate, and a horizontal polarization radiation patch and a feed network which are printed on the upper surface and the lower surface of the dielectric substrate; the metal coupling patch comprises a metal disc and a metal circular ring nested on the circumference of the metal disc; the horizontal polarization radiation patch is connected with the metal disc through a first short-circuit line, and the metal ring and the horizontal polarization radiation patch are connected with the metal floor through four second short-circuit lines and four third short-circuit lines respectively. Through short-circuit connection between the horizontal polarization radiation patch and the metal disc and between the metal circular ring and the horizontal polarization radiation patch and the metal floor, coupling between the horizontal polarization radiation body and the vertical polarization radiation body is achieved, the electrical length of the antenna is further prolonged, the bandwidth of the antenna can be effectively widened, and the profile of the antenna can be effectively reduced.

The invention relates to the technical field of antennas, and further relates to a wide-beam multi-vibrator planar antenna supporting Tiantong Beidou frequency bands, which comprises a multi-vibrator radiation array element layer, a coplanar feed-amplitude shaping network, a stepped impedance matching section, a low-loss double-layer dielectric laminated layer and a metal reflecting plate, the outermost side of the multi-oscillator radiation array element layer is a PCB lamination layer; the coplanar feed-amplitude shaping network comprises a radiation patch, and different current amplitudes are provided for all oscillators through phase shift sections with different electric lengths so as to ensure that the half-power beam width can still reach 90 degrees or above under the condition of the shortest Beidou wavelength; the stepped impedance matching section is a pi-shaped converter formed by connecting three microstrip lines with different widths in series; and the low-loss double-layer dielectric laminated layer is used for solving the minimum distance between the metal reflecting plate and the PCB laminated layer according to the theoretical minimum gain. The antenna has the advantages of compact structure, stable gain and wide beam width.

The invention provides terminal equipment. The terminal equipment comprises a metal floor, a radiation branch knot and a feed source, the radiation branch knot is adjacent to and parallel to the preset edge of the metal floor, the projection of the radiation branch knot on the preset edge of the metal floor is located in the preset edge, and the radiation branch knot comprises at least one connecting part connected with the preset edge of the metal floor; the feed source is electrically connected with the radiation branch knot and is used for exciting the radiation branch knot to generate excitation current conducted along a first direction, so that the preset edge of the metal floor generates floor current, and the direction of the floor current of a first area corresponding to the radiation branch knot in the preset edge of the metal floor is a second direction; the direction of floor current in a second area in the preset edge of the metal floor is a first direction, the second area is adjacent to the first area, and the second direction is opposite to the first direction; the radiation branch comprises a main branch whose electrical length is 1 / 2 of the wavelength corresponding to the preset frequency band. Due to the current distribution, the directivity coefficient after far-field radiation electric field vector superposition is reduced, and the omni-directivity of the antenna is improved.

According to an embodiment, a plasma processing system includes a plasma chamber, an RF source, a matching circuit, a balun, and a resonating antenna. The resonating antenna includes a first and a second spiral resonant antenna (SRA), each having an electrical length corresponding to a quarter of a wavelength of a frequency of a forward RF wave generated by the RF source. The first end of the first SRA is coupled to a first balanced terminal of the balun and the second end of the first SRA is open circuit. The first end of the second SRA is coupled to a second balanced terminal of the balun and the second end of the second SRA is open circuit. The first and the second SRA are arranged in a symmetrically nested configuration having a same center point.

The invention relates to the technical field of electromagnetic fields and microwaves, and provides an ultra-wideband tight coupling metal dipole antenna array with a wave trapping characteristic, which comprises a tight coupling metal dipole array positioned at the lower part and a planar wave absorbing structure positioned at the upper part, the tight coupling metal dipole array comprises M * N metal dipole units, the planar wave absorbing structure comprises M * N planar wave absorbing units, and each metal dipole unit comprises a left gradual change type dipole arm, a right gradual change type dipole arm, a left coupling metal piece, a right coupling metal piece, a feed printed board, a planar metal floor and a feed coaxial line; the planar wave absorbing unit comprises a supporting dielectric sheet, a planar dielectric substrate and printed patch layers, and the printed patch layers are printed on the upper surface and the lower surface of the planar dielectric substrate. And the central frequency point and the bandwidth of the notch frequency band can be adjusted by changing the electrical length and the rotation angle of the patch in the printed patch layer.

Provided in the present application is a terminal device, which comprises a metal ground plane, a radiating element and a feed source. The radiating element is arranged adjacent to and in parallel with a predetermined side of the metal ground plane, and the projection thereof on the predetermined side of the metal ground plane is located within the predetermined side. The radiating element comprises at least one connection portion connected to the predetermined side of the metal ground plane. The feed source is electrically connected to the radiating element and is used for exciting the radiating element to generate an excitation current conducted in a first direction, so that the predetermined side of the metal ground plane generates a ground plane current, wherein the direction of the ground plane current in a first region in the predetermined side of the metal ground plane corresponding to the radiating element is a second direction, and the direction of the ground plane current in a second region in the predetermined side of the metal ground plane is the first direction, the second region being adjacent to the first region, and the second direction being opposite to the first direction. The radiating element comprises a main element of which the electrical length is 1 / 2 of the wavelength corresponding to a preset frequency band. Such a current distribution reduces the directivity coefficient after vector superposition of far-field radiation electric fields, thereby improving the omnidirectionality of antennas.

The invention provides a three-dimensional frequency selector based on slow-wave loading slot lines, which comprises a plurality of slow-wave loading slot line units arranged periodically, and is characterized in that the slow-wave loading slot line units adjacent to each other along an x axis are separated by air layers to form periodic gaps in the x-axis direction; the adjacent slow wave loading slot line units along the y axis are directly connected; and the slow wave loading slot line unit comprises a slot line along the z-axis direction and a T-shaped metal patch loaded in a slot line gap. According to the invention, through x-y plane two-dimensional periodic arrangement and z-direction slot line gap extension, a three-dimensional structure is formed, and incident wave frequency selection is realized; after the T-shaped metal patch is loaded on the slot line, the equivalent electrical length is increased, and the phase velocity is reduced, so that the structure realizes the target space filtering characteristic under the condition of compact size.

According to an embodiment, a plasma processing system is proposed. The plasma processing system includes a plasma chamber; an RF source configured to generate a forward RF wave; an impedance matching circuit coupled to the RF source, the impedance matching circuit configured to provide matching for the RF source; a balun having unbalanced terminals coupled to the impedance matching circuit; and a resonant antenna configured to generate plasma within the plasma chamber, the resonant antenna being a spiral resonant antenna with an electrical length corresponding to a half-wavelength of a frequency of the forward RF wave, the resonant antenna comprising: a first tap along the spiral resonant antenna coupled to a first balanced terminal of the balun and a second tap along the spiral resonant antenna coupled to a second balanced terminal of the balun.

An antenna assembly, an electronic device main body, an electronic device, a storage medium and a control method of the electronic device, the antenna assembly comprises a circuit board, a main radiator, a parasitic radiator and a switching circuit, the main radiator is connected with a feed circuit of the circuit board, and the parasitic radiator is connected with the switching circuit. And the switching circuit is used for enabling the main radiator to feed the parasitic radiator under the conduction condition, and the switching circuit is used for enabling the main radiator not to feed the parasitic radiator under the turn-off condition. The parasitic radiator is controlled by the switching circuit, and the switching circuit can enable the main radiator to feed the parasitic radiator, so that the electrical length of the antenna assembly can be increased, and the antenna efficiency of the antenna assembly can be improved. In some application scenarios, if the parasitic radiator participates in radiation, the antenna performance is deteriorated, and the parasitic radiator can be controlled not to participate in radiation of wireless signals through the switching circuit, so that the antenna assembly can maintain better antenna performance in various application scenarios.

This application provides an antenna system and an electronic device, relating to the field of electronic device technology, enabling the antenna system on the electronic device to simultaneously consider both directivity and hand grip performance in landscape mode. The antenna system includes a first antenna, the radiator of which includes a first stub and a second stub; the first stub is disposed on a first side of the electronic device, the second stub is disposed on a second side of the electronic device, a first feed point is disposed at the connection between the first stub and the second stub, a first ground point is located on the portion of the radiator between the first feed point and the first end, and the electrical length of this portion of the radiator is 1 / 2 wavelength to 1 wavelength; a second ground point is located on the portion of the radiator between the first feed point and the second end, and the electrical length of this portion of the radiator is 1 / 8 wavelength to 1 / 2 wavelength. The antenna system provided by this application is used for signal transmission and reception.

A Doherty amplifier according to the present disclosure comprises a main amplifier, an auxiliary amplifier, a distribution circuit that distributes signals to the main amplifier and the auxiliary amplifier, and a phase compensation circuit. The main amplifier has a first input matching circuit and a plurality of main amplification stages. The auxiliary amplifier has a second input matching circuit and a plurality of auxiliary amplification stages. The distribution circuit has a first line connected to the first input matching circuit and a second line connected to the second input matching circuit. The electrical length of the first line is such that the input impedance of the first line is higher than the characteristic impedance of the first line and the imaginary component is less than 10% of the real component when a small signal is input. The electrical length of the second line is such that the input impedance of the second line is higher than the characteristic impedance of the second line and the imaginary component is less than 10% of the real component when a small signal is input. The phase compensation circuit is provided in an inter-stage matching circuit of the plurality of main amplification stages or the plurality of auxiliary amplification stages.

The present invention discloses a reconfigurable frequency MEMS standing wave meter based on a multi-port annular junction and a preparation method thereof, which is mainly composed of an annular directional coupler, a MEMS thermoelectric microwave power sensor and a MEMS variable capacitor. Two thermoelectric MEMS microwave power sensors located at the coupling port and the isolation port of the annular directional coupler respectively measure the output microwave power at the coupling port and the isolation port, thereby obtaining the magnitude of the incident microwave power and the reflected microwave power, and thus obtaining the magnitude of the standing wave ratio; six identical MEMS variable capacitors are equidistantly placed on the annular directional coupler, and different driving voltages are applied to the driving electrodes to change the height of the MEMS double-ended fixed beam, thereby changing the electrical length between the ports of the annular directional coupler, and realizing continuous tuning of the working frequency of the microwave standing wave meter. The present invention has the characteristics of miniaturization and tunability, is compatible with silicon-based CMOS technology, and is easy to integrate.

The invention discloses a center temperature detector and a combined cooking utensil with the center temperature detector. The invention relates to a center temperature detector (28) for a combination cooking appliance (10). The center temperature detector (28) comprises a measuring portion (32) and a handle portion (30). Furthermore, a contact tube (50) is provided, in which the cable (36) is guided. The cable (36) has an unsheathed region (88) in the handle part (30), in which unsheathed region (88) the contact tube (50) forms a contact point (90) together with the cable (36), the contact point (90) having a distance d1 to the handle-side end (52), which distance d1 corresponds to an electrical length of the microwave radiation in the handle part (30), the electrical length is shorter than or equal to a quarter of the wavelength of the microwave radiation used in the combination cooking appliance (10). The invention also relates to a combination cooking appliance (10) comprising a central temperature detector (28).

The application discloses a terahertz metasurface reflection unit based on a MEMS switchable delay line, and belongs to the field of radio frequency front-end devices.The unit adopts a sandwich structure of upper and lower glass substrates and a middle bonded metal surface, and a metal radiation patch, a phase delay line and a MEMS switch are integrated on the upper surface.The core is to control the on-off state of the phase delay line through the MEMS switch: when the switch is turned off, the unit is in a reference electrical length;when the switch is turned on, the current path is lengthened, so that the reflection phase lags by about 180 degrees, thereby realizing 1-bit phase coding.The design ingeniously combines the MEMS switch and the delay line, has the advantages of low driving voltage, low reflection loss and high phase control precision in the terahertz frequency band, and provides a feasible hardware solution for the practical application of a reconfigurable intelligent surface in a terahertz communication system.

The invention discloses a quasi-true time delay broadband beam forming network with Chebyshev amplitude distribution. The quasi-true time delay broadband beam forming network comprises a 3 * 4 beam forming network, a 4 * 4 true time delay network, an input port, an output port and the like. The 3 * 4 beam forming network comprises first to tenth parallel double-line couplers, first to seventh open-short circuit stub loading transmission lines and first to fourth 50-ohm transmission lines; the 4 * 4 real time delay network comprises first to eleventh real time delay circuits and first to fourth connecting lines. Broadband Chebyshev amplitude output is obtained by setting different coupling coefficients of the first to tenth parallel double-line couplers. In-band flat phase difference output is obtained by setting phase shift values of the first to fourth 50-ohm transmission lines, phase shift values of the first to seventh open-short circuit stub loading transmission lines and impedance values and electrical lengths of the open-short circuit stubs; through controlling the first to eleventh true time delay circuits, the phase slope between the output ports has a frequency-dependent characteristic, and after the antenna is connected, a consistent beam direction in a broadband range is obtained.

Provided in the present application is a terminal device, which comprises a metal ground plane, a radiating element and a feed source. The radiating element is arranged adjacent to and in parallel with a predetermined side of the metal ground plane, and the projection thereof on the predetermined side of the metal ground plane is located within the predetermined side. The radiating element comprises at least one connection portion connected to the predetermined side of the metal ground plane. The feed source is electrically connected to the radiating element and is used for exciting the radiating element to generate an excitation current conducted in a first direction, so that the predetermined side of the metal ground plane generates a ground plane current, wherein the direction of the ground plane current in a first region in the predetermined side of the metal ground plane corresponding to the radiating element is a second direction, and the direction of the ground plane current in a second region in the predetermined side of the metal ground plane is the first direction, the second region being adjacent to the first region, and the second direction being opposite to the first direction. The radiating element comprises a main element of which the electrical length is 1 / 2 of the wavelength corresponding to a preset frequency band. Such a current distribution reduces the directivity coefficient after vector superposition of far-field radiation electric fields, thereby improving the omnidirectionality of antennas.

Embodiments of the present application relate to an amplifying device and a transmitter. An amplifying device and a transmitter capable of compensating for a parasitic component of a circuit element without complicating a circuit structure are provided. The amplifying device includes a first amplifier that performs an amplifying operation on a signal; N-1 second amplifiers that perform an amplifying operation on the signal in sequence according to an amplitude of the signal in a case where the first amplifier performs the amplifying operation; N input networks connected to an input terminal that inputs the signal; N output networks connected between an output node of the first amplifier and a load connection node and connected between output nodes of the N-1 second amplifiers and the load connection node; and a first bias network that supplies a direct current bias voltage to at least one of the N output networks, an electrical length of the first bias network being less than 90 degrees.

The transmission path length detection device (3) is configured to include: a first electrostatic capacitance calculation unit (21) which observes the voltage change of the transmission path (2) in the communication network and calculates the overall electrostatic capacitance of the transmission path (2), i.e., the total electrostatic capacitance, based on the voltage change; a second electrostatic capacitance calculation unit (22) which measures the characteristic impedance of the transmission path (2) and calculates the electrostatic capacitance per unit length of the transmission path (2) based on the characteristic impedance; and an electrical length calculation unit (23) which divides the total electrostatic capacitance calculated by the first electrostatic capacitance calculation unit (21) by the electrostatic capacitance per unit length calculated by the second electrostatic capacitance calculation unit (22) to thereby calculate the electrical length of the transmission path (2).

The utility model discloses a microstrip patch antenna which comprises a dielectric substrate and a radiation patch. The radiation patch is arranged on the dielectric substrate, the radiation patch is E-shaped, the parallel edge of the E-shaped radiation patch is defined as a first sub-radiation patch, the vertical edge of the E-shaped radiation patch is defined as a second sub-radiation patch, and the length of the first sub-radiation patch is larger than or equal to 2.1 mm and smaller than or equal to 2.5 mm. The E-shaped structure enables the current to bypass between the first sub radiation patch and the second sub radiation patch, which is equivalent to increasing the electrical length of the radiation patch and reducing the resonant frequency of a fundamental mode, so that the low-frequency band bandwidth is broadened; the edges of the first sub-radiation patch and the second sub-radiation patch can generate strong electromagnetic field coupling to excite an additional parasitic resonance mode, so that the frequency band is further widened, and the bandwidth of the microstrip patch antenna is effectively widened. Wherein the first sub radiation patch of 2.1 mm to 2.5 mm enables the resonant frequency of the microstrip patch antenna to range from 43.7 Ghz to 55.1 Ghz, the relative bandwidth is 23%, and high bandwidth is achieved.

Embodiments of the present application provide a calibration device, a differential clamp, and related devices and systems. The calibration device includes a non-equivalent length reflection calibration piece for calibrating a scattering parameter of a differential signal obtained based on the differential clamp. The non-equivalent length reflection calibration piece includes a first line and a second line. An electrical length of the first line is not equivalent to an electrical length of the second line. A difference between a length of the first line and a length of the second line is within a preset range. The preset range is determined based on a bandwidth of the differential signal. Embodiments of the present application can accurately obtain the scattering parameter of the differential signal in the case of using the differential clamp.

Distribution element high-frequency (HF) filter, comprising: a ceramic substrate that has a grounding plate on a first surface of the substrate; a first resonator on a second surface of the substrate opposite the first surface, wherein the first resonator is electrically connected to a first input / output interface (I / O interface) near a first end of the substrate; a second resonator on the second surface of the substrate, wherein the second resonator is electrically connected to a second I / O interface near a second end of the substrate opposite the first end; one or more intermediate resonators on the second surface of the substrate, wherein the one or more intermediate resonators are located between the first and the second resonator, wherein each of the first, second and one or more intermediate resonators has an electrical length that nominally corresponds to half a wavelength of a center frequency of the filter, wherein each of the first, second and one or more intermediate resonators comprises a resonator section between first and second resonator end sections, which are electrically connected to the grounding plate by a conductive wall near a common side of the substrate, wherein each resonator at least partially surrounds a section of the surface of the substrate on which the resonator is located.

A broadband low insertion loss limiter chip based on a hybrid π-type topology, belonging to the technical field of microwave passive devices, solves the problems of high small-signal insertion loss, narrow operating bandwidth and large size of existing microwave limiters; by replacing the quarter-wavelength transmission line between the limiter circuits with a capacitive-loaded hybrid π-type structure, the electrical lengths of the first and second tapered U-shaped transmission lines in the two hybrid π-type structures are much less than 90° and are bent, reducing the area of the limiter chip; the first-stage limiter circuit reduces the total equivalent capacitance, thereby reducing the insertion loss; the electrical length of the transmission line is shortened, and its physical length is correspondingly shortened, reducing the insertion loss; in the two hybrid π-type structures, the total turn-off capacitance of each stage of the limiter circuit is absorbed into the hybrid π-type structure, making the limiter equivalent to a quasi-50-ohm transmission line model at small signals, thereby eliminating the influence of the turn-off capacitance reactance loaded on the transmission channel on impedance matching and expanding the operating bandwidth of the limiter.

The invention belongs to the field of superconducting receiving, and provides an HTS filter based on a full-wavelength resonator in order to improve the power capacity of the HTS filter, the HTS filter comprises a dielectric substrate, an HTS film is deposited on the first surface of the dielectric substrate, and a grounding metal layer is arranged on the second surface opposite to the first surface; the microstrip resonant structure is formed on the HTS thin film of the dielectric substrate and comprises at least two full-wavelength resonators, the adjacent full-wavelength resonators realize electromagnetic coupling through a gap, and the equivalent electrical length of each full-wavelength resonator is a waveguide wavelength corresponding to the working center frequency of the HTS filter; and the input port and the output port are respectively coupled with the full-wavelength resonator on the outermost side in the micro-strip resonant structure through micro-strip feeder lines. According to the technical scheme, the full-wavelength resonator structure with the equivalent electrical length as the waveguide length is adopted, so that the radio-frequency current can be redistributed along a longer resonance path, and the power capacity of the HTS filter is improved on the premise that the device size and the manufacturing complexity are not remarkably increased.

The invention relates to a low-profile antenna which is distributed in a central symmetry manner, and comprises a radiation unit which is located on a dielectric plate and comprises a plurality of radiation patches with arc edges and a plurality of parasitic patches; orthographic projections of the plurality of radiation patches and the plurality of parasitic patches on the top surface of the dielectric plate are alternately arranged along the circumferential direction; wherein the plurality of radiation patches extend towards the center of the dielectric plate along the radial direction of the dielectric plate and are connected, a slot line which partially penetrates through the parasitic patch is formed by the parasitic patch, and a preset distance is formed between the slot line and the center; the grounding device comprises metal plates which are arranged at the periphery of the radiation unit and are in one-to-one correspondence with the parasitic patches, and metal columns of which the two ends are respectively connected with the metal plates and the circuit board; one end of the coaxial feeder line is located in the center and connected with the radiation patches, and the other end of the coaxial feeder line is connected with the circuit board, so that the sum of the electrical lengths of any radiation patch and the coaxial feeder line is located in a preset range. The antenna can realize miniaturization and low profile in an L frequency band, and has a wide beam characteristic and a relatively wide working bandwidth at the same time.

Provided is an electronic device including an antenna for performing wireless communication, a noise source that causes generation of radiation current, and a conductive member that is disposed on a propagation path of the radiation current from the noise source to the antenna and has a projecting portion projecting from the propagation path. An electrical length to a tip end of the projecting portion is equal to or larger than one-eighth but equal to or smaller than three-eighths of a wavelength used in the wireless communication.

The present invention proposes a broadband, low-profile, dual-polarization omnidirectional antenna, comprising a horizontally polarized radiator, a metal coupling patch, a vertically polarized radiator, and a metal floor, arranged sequentially from top to bottom. The horizontally polarized radiator comprises a dielectric substrate, and horizontally polarized radiating patches and a feed network printed on its upper and lower surfaces. The metal coupling patch comprises a metal disk and a metal ring nested on its circumference. The horizontally polarized radiating patch and the metal disk are connected via a first short-circuit line, and the metal ring and the horizontally polarized radiating patch are connected to the metal floor via four second short-circuit lines and four third short-circuit lines, respectively. The present invention achieves coupling between the horizontally polarized radiator and the vertically polarized radiator by short-circuiting the horizontally polarized radiating patch and the metal disk, and the metal ring and the horizontally polarized radiating patch and the metal floor, thereby extending the electrical length of the antenna, effectively broadening the antenna's bandwidth, and reducing the antenna's profile.

A transmission circuit (10) is provided with: an input terminal (T0) for receiving a high-frequency signal; output terminals (T1, T2); amplification circuits (105A, 105B); a connection line (145); output circuits (170A, 170B); and switches (S1A, S1B). Each amplification circuit amplifies the high-frequency signal received at the input terminal. The output circuit (170A) transmits a signal amplified by the amplification circuit (105A) to the output terminal (T1). The output circuit (170B) transmits a signal amplified by the amplification circuit (105B) to the output terminal (T2). Each amplification circuit includes a carrier amplifier, a peak amplifier, and a hybrid coupler. In each amplifier, the carrier amplifier and the peak amplifier are respectively connected to two input terminals of the hybrid coupler. A corresponding output circuit is connected to one output terminal of the hybrid coupler. Each switch is connected to the other output terminal of the hybrid coupler. One output terminal of one hybrid coupler and one output terminal of the other hybrid coupler are interconnected via the connection line. High-frequency signals of mutually different phases are supplied to the first and second amplification circuits. The connection line has the same electrical length as that of at least one phase shift line of the hybrid couplers.

The application discloses a balanced-to-balanced coaxial line impedance transformer, and belongs to the electronic technical field.The coaxial line impedance transformer is composed of four coaxial lines with the same characteristic impedance and electrical length, the coaxial line has an inner conductor and an outer conductor, the coaxial line impedance transformer has two balanced radio frequency ports Z L and Z H , and the 2.25:1 Z H / Z L impedance transformation ratio is realized by connecting the inner conductor and the outer conductor between different ports of the four coaxial lines.The application breaks through the minimum impedance transformation ratio of 4:1 that can be realized by the prior art, can satisfy the impedance transformation requirement below 4:1, can be combined with other impedance transformers to realize the impedance transformation ratio with smaller discrete value, is helpful to the miniaturization, low insertion loss and multi-path power synthesis scheme, and can satisfy the high power and high efficiency application demand above 2kW.

An electronic device. The electronic device may comprise any one of a handheld device, an onboard device, a wearable device, a terminal device or other devices connected to a wireless modem, a cellular phone, a smart phone, a personal digital assistant, a computer, a tablet computer, a portable computer and the like. In the embodiments of the present application, with the positions of a first feed terminal and a grounding terminal unchanged, a first metal connecting arm in the embodiments of the present application is provided with an intermediate section arranged with a clearance; the electrical circuit length of an antenna formed by a metal frame radiation segment is equal to the sum of the length of the section of the metal frame radiation segment between a first connection position and a second connection position and the length of the intermediate section; and the intermediate section increases the total length of the antenna to a certain extent, so as to increase the length of the antenna connected between the first feed terminal and the grounding terminal. In the embodiments of the present application, the intermediate section enables radiated electrical signals of the antenna to have longer low-frequency, and the resonance to be lower under a same matching condition, so that the resonance is lower when the metal frame radiation segment is of a same length, thus solving the problems of higher resonance and efficiency reduction caused by insufficient electrical length under compact layouts.

The utility model discloses a topological structure, comprising a parallel three-line, a first open-circuit branch, a second open-circuit branch, an input port and an output port, one end of the parallel three-line is respectively connected with the input port and the output port, and the other end of the parallel three-line is respectively connected with the first open-circuit branch and the second open-circuit branch. The first open-circuit branch knot and the second open-circuit branch knot are bilaterally symmetrical about the parallel three lines, and the electrical length of the parallel three lines, the electrical length of the first open-circuit branch knot and the electrical length of the second open-circuit branch knot are all 1 / 4 wavelengths corresponding to the center frequency of the band-pass filter based on the topological structure. And the characteristic impedance of the first open-circuit branch knot is equal to that of the second open-circuit branch knot. The utility model further discloses a high-selectivity broadband band-pass filter based on the topological structure, and the high-selectivity broadband band-pass filter has the advantage of high selectivity.