122results about How to "Wide working frequency band" patented technology

The invention discloses a bulk acoustic resonator based on a mono-crystal piezoelectric film. The bulk acoustic resonator includes a substrate, an acoustic reflection layer formed on the substrate, and a piezoelectric sandwich structure covering the acoustic reflection layer. The piezoelectric sandwich structure includes a lower electrode, a mono-crystal piezoelectric film, and an upper electrode. A metal film is deposited on the surface of the lower electrode and on the acoustic reflection layer, and a patterned bonding fulcrum is formed through a lithography process, and therefore, the piezoelectric sandwich structure and the acoustic reflection layer are bonded at low temperature. The mono-crystal piezoelectric film is obtained through crystal ion slicing, and the thickness of the film can be controlled by controlling the energy of ion implantation and the ion dose. The bulk acoustic resonator prepared in the invention has an electromechanical coupling coefficient above 44% and a quality factor above 2500, and can play an important role in the modern communication system featuring high-bandwidth and large-capacity data transmission.

The invention provides an angle tracking system, which is characterized by comprising a control center, an antenna branch system, a feeder line branch system, an emission branch system, a receiving branch system, a servo branch system and a communication interface branch system. The angle tracking system can search, capture and track unmanned airplanes, precisely position the unmanned airplanes according to orientation information, elevation measurement information and information frame ranging information which are acquired by an angle tracking branch system, emit real-time remote control signals of a flying state of the unmanned airplane and a working state of airborne equipment, and receive real-time remote sensing signals of a flying parameter and detection information of the unmannedairplane and the working state of the airborne equipment; each working row channel is provided with a plurality of frequency points; and the working frequency band is wide, and the anti-interference performance is high.

The invention discloses a single pulse wide angle electric scanning reflective array antenna comprising a reconfigurable reflective array surface (1), a polarization grid (2), a bias voltage circuit (3), a wave control machine (4), a control processor (5) and a feed source subsystem (6). The size of the caliber of the polarization grid (2) is equal to that of the caliber of the reconfigurable reflective array surface (1), and the polarization grid (2) is positioned above the reconfigurable reflective array surface (1). A radiation aperture surface of a feed source (61) is parallel and level to the reconfigurable reflective array surface (1) and is positioned at the center of the reflective array surface. The single pulse wide angle electric scanning reflective array antenna adopts a spatial feed mode, that is to say, the feed source irradiates the polarization grid and feeds the array surface after reflection. A polarization grid structure is applied to a reconfigurable reflective array antenna, and the feed source, the polarization grid and the reflective array surface form a double reflective structure, therefore, the performance of an antenna structure is excellent, the antenna structure can facilitate the installation of an antenna port and the connection of the antenna port and a radar system, and the antenna is compact in structure with a low section.

The invention belongs to a network test technology, and particularly relates to an integrated network parameter tester and an integrated network parameter test method applied to a pulse regime. The tester comprises a built-in pulse generator module and a pulse modulation module connected with the pulse generator module. An excitation signal source module is connected with the pulse modulation module. The pulse modulation module is connected with a pulse high-power S parameter test module. The pulse high-power S parameter test module and a local oscillator signal source module are connected with a mixing receiver module respectively. The mixing receiver module is connected with an intermediate frequency processing module. The intermediate frequency processing module is connected with an embedded computer module through a digital signal processing module. By the tester and the test method, the shortcomings of large volume and high construction cost of the conventional test instrument are overcome; and network parameters can be flexibly and conveniently tested.

The invention discloses a small-size beam controllable patch antenna based on a reconfigurable parasitic element, and the antenna comprises an E-shaped main radiation patch, a left parasitic patch anda right parasitic patch. Through employing a CSRR structure, the antenna reduces the electrical length of a parasitic patch, and facilitates the miniaturization of the parasitic patch. A PIN diode isadded to CSRR structure for providing different DC bias voltages, thereby enabling a single parasitic element to work at two states: a director and a reflector. The combination of different states ofthe left and right parasitic elements can enable the main lobe direction of a radiation beam of the antenna to be switched among 0 degree, -30 degree, and 30 degrees, thereby achieving the beam controllable performance of the antenna, and effectively enlarging the beam scanning range of the antenna. The antenna employs the coaxial feed E-shaped main radiation patch and introduces an air layer structure between two dielectric substrates, thereby effectively enlarging the work bandwidth of the antenna. The antenna is high in gain, is high in front-to-rear ratio, and is low in profile.

The invention discloses a frequency band expanding structure of a terminal antenna. The frequency band expanding structure comprises a metal rear cover, a metal middle frame and a metal coupling piece. The metal middle frame is arranged on the periphery of the metal rear cover. Two disconnected gaps are formed in the bottom of the metal middle frame. The part, located between the two disconnected gaps, of the metal middle frame serves as an antenna irradiation body. The antenna irradiation body is provided with a feeding point, a grounding point and a metal middle frame wire connected to the disconnected gaps. By means of the metal middle frame wire, the low-frequency-band bandwidth and the high-frequency-band bandwidth resonated by the antenna irradiation body can be adjusted; the metal coupling piece is arranged at the tail end of the antenna irradiation body and located at the target position around the grounding point and is connected with the metal irradiation body through a metal short connecting needle so that the low-frequency-band bandwidth or the high-frequency-band bandwidth can be expanded through the coupling between the metal coupling piece and the antenna irradiation body, wherein the metal coupling piece is parallel to the top of the metal rear cover.

The invention discloses a high-gain narrowband radio frequency receiver. The high-gain narrowband radio frequency receiver includes a radio frequency front-end amplification and filtering circuit, a frequency mixing circuit, a multistage numerical control gain amplification circuit, a first-stage intermediate frequency filter, an N-stage intermediate frequency filter, an ADC matching network and an ADC; the radio frequency front-end amplification and filtering circuit is used for amplifying and filtering radio signals and inputting the amplified and filtered radio signals to the frequency mixing circuit; the frequency mixing circuit is used for performing frequency conversion on the radio frequency signals to obtain intermediate-frequency signals and outputting the intermediate-frequency signals to the first-stage intermediate frequency filter; the first-stage intermediate frequency filter is used for filtering the signals and sending the filtered signals to the multistage numerical control gain amplification circuit; the multistage numerical control gain amplification circuit is used for amplifying the signals and sending the amplified signals to the N-stage intermediate frequency filter; the N-stage intermediate frequency filter is used for filtering the signals and sending the filtered signals to the ADC matching network; and the ADC is used for converting signals outputted by the ADC matching network into digital signals. With the high-gain narrowband radio frequency receiver of the invention adopted, under a condition that blocking signals exist, a high-gain link can maintain unsaturated, sensitivity will not be deteriorated, and gain can be as high as 80db.

The invention discloses electronic control terahertz polaroid based on graphene, the electronic control terahertz polaroid includes at least two layers of graphene layers, each layer of graphene is of a grid band structure, a dielectric layer is arranged between each two layers of adjacent graphene layers, and the dielectric layer separates the two layers of graphene layers; an even number of layers of graphene layers are jointly connected to an electrode, an odd number of layers of graphene layers are jointly connected to the other electrode, and the two electrodes are loaded with voltage and voltage regulation can be realized. The polaroid prepared by use of a multilayer film structure can regulate performance parameters such as a response frequency band and the degree of polarization through structure parameters of grid bands such as the width and space periods of the grid bands and the number of layers of graphene; and through voltage regulation, the degree of polarization penetrating through terahertz waves can be actively regulated, and the function of selective modulation of terahertz waves in different directions of polarization can also be realized.

The invention provides an antenna device for receiving a radio broadcasting signal, which comprises an antenna unit, a first matching circuit, a second matching circuit, and a switching circuit, wherein the antenna unit receives the radio broadcasting signal; the first matching circuit and the second matching circuit receive the radio broadcasting signal from the antenna unit; and the switching circuit is connected among the antenna unit, the first matching circuit and the second matching circuit, receives a selective signal, and gates the first matching circuit or the second matching circuit to transmit the radio broadcasting signal according to the selective signal. The antenna device gates one matching circuit corresponding to a frequency range of a CMMB (China Mobile Multimedia Broadcasting) signal to be received through a combination of the switching circuit and the two matching circuits, so that a working frequency range of an antenna when the antenna receives the CMMB signal is widened, and the signal receiving stability is improved.

The invention provides a vivaldi antenna and a dual-polarized probe, which solves the problems of poor high-frequency cross-polarized levels and low port coupling isolation of existing probe antennas.The technical points are that the vivaldi antenna comprises three metal layers and dielectric plates arranged between each two adjacent metal layer; the intermediate metal layer is provided with a feeding structure, and the other two metal layers are provided with vivaldi antenna radiation structures electrically connected to the feeding structure; and the two vivaldi antenna radiation structuresare symmetric along the center line of the antenna to realize the double-grooved vitaldi structure, which effectively improves low-end standing waves, so that the antenna has a good high-frequency cross-polarization level and has a relatively high isolation degree. Meanwhile, by arranging a clamping groove in the center line position of each antenna, the orthogonal connection of two vivodi antennas can be realized by using the clamping grooves to form a dual-polarized probe, and the vivaldi structures are respectively arranged on the two sides of each clamping groove to avoid destroying the circular back cavities of the vitaldi structures. The phase centers of the two antennas of the probe can be aligned without destroying the circular slit back cavities of the vitaldi structures.

The invention discloses an ultra-wide-band miniaturized phase shifter unit and a linkage mechanism thereof. The ultra-wide-band miniaturized phase shifter unit comprises an upper shielding plate, a lower shielding plate and a pull rod, wherein two axisymmetric sub units are arranged between the upper shielding plate and the lower shielding plate by taking the pull rod as a shaft; each sub unit comprises a transmission sliding plate, medium blocks and a conductor band; the transmission sliding plate is connected to the pull rod; a straight slot and a tilted slot are formed in the surface of the transmission sliding plate; the medium blocks are mounted on the upper end face and the lower end face of the transmission sliding plate; a first guide block and a second guide block are arranged on the lower shielding plate and are used for positioning the longitudinal movement of the transmission sliding plate and the transverse movement of the medium blocks. The ultra-wide-band miniaturized phase shifter unit has the advantages of miniaturization, high mutual adjustment performance, easiness in implementation of high upper sidelobe suppression, simple structure processing and assembling technology, high reliability, wide working frequency band, high generality, adaptability to 2G, 3G and 4G base station antennas and the like.

The invention relates to the field of an underwater sound metering test, which is mainly a hydrophone phase low-frequency calibration tube comprising a metal rigid tube body; the metal rigid tube bodyis internally provided with a calibration tube cavity and an energy converter cavity which are communicated; the calibration tube cavity is used for containing liquid medium and forming a liquid column, and the thickness of the tube wall of the metal rigid tube body is larger than or equal to the radius of the calibration tube cavity; a supporting step of the bottom part of the calibration tube cavity is provided with a soft rubber vibrating membrane, a vibrating piston is connected below the soft rubber vibrating membrane, a vibrating coil is bonded and fixed at the back surface of the vibrating piston by epoxy resin, and the center line of the soft rubber vibrating membrane, the center line of the vibrating piston and the center line of the vibrating coil are completely coincided with the center line of the metal rigid tube body; and the energy converter cavity is internally provided with a piston-type electrodynamic energy converter. The invention has the beneficial effects of: being applicable to measurement and calibration of the small-size hydrophone low-frequency acoustic characteristic, being characterized by low frequency, wide band, oil resistance, water-leakage prevention and corrosion resistance and the like and having good time stability and temperature stability.

The invention provides a radiation structure and an array antenna. The radiation structure comprises a radiation fin with a radiation slot in the middle. The radiation slot consists of a transverse slot and a longitudinal slot, which are communicated with each other and are cross-orthogonal. The length of the transverse slot and the length of the longitudinal slot are less than the length of the radiation fin in the extending direction of the corresponding radiation slot. By adding the radiation slot to the radiation fin, the radiation structure can produce two kinds of radiation synchronouslywhen working in an antenna system, so as to achieve an effect of polarization vector superposition enhancement. Thus, the same radiation efficiency and radiation gain of the multi-layer patch structure in the traditional antenna can be achieved by only one layer of radiation fin, fewer components are used, the structure is simple, the antenna profile can be reduced, and antenna miniaturization isfacilitated.

The invention discloses a testing system and method for phase consistency among frequency variable T / R assembly channels and belongs to the technical field of testing. According to the system and the method, reference channels and calibration channels work in a passive state, do not consume power, do not generate heat, do not generate temperature drift and are high in testing accuracy; according to the reference channels and the calibration channels established by introducing double-balanced mixers and lowpass filters, so full-double two-port calibration is possible and the testing accuracy is improved; power supply, state control and transmitting signal regulating devices do not need to be arranged for the reference channels, so system components are simplified, and system construction costs are reduced; the working bands of the double-balanced mixers are relatively wide; frequency unchangeable and one-time frequency variable reference channels and calibration channels are established through switching of switches, so certain university is achieved; and the lowpass filters are introduced into the input and output ports of the reference channels and the calibration channels, so unnecessary spectrum components are filtered, and the accuracy of a testing result is improved.

The invention discloses a low-noise amplifier structure. The low-noise amplifier structure comprises a bandgap reference circuit (Bandgap), a digitally-controlled gain circuit (DCG), a signal amplification circuit (Amplifier) and a notch filter circuit (IRnotchfilter) with an adjustable image rejection frequency. An operating frequency signal Vop is amplified through antenna reception, an image signal Vim under image frequency is rejected, and an effective signal is further amplified by a capacitance and inductance resonant circuit (LCtank) to obtain an image rejection (IR) gain response from the reception to the output; through a digital control part, an input quiescent point is controlled so as to maximize the gain of an operating frequency point. The image signal is rejected, namely the gain of the image frequency im is reduced through a notch filter network, a load resonant frequency is higher than the image frequency so to enhance the rejection performance on an image frequency output signal and improve the performance of low-noise amplifier, and thus the overall performance of a superheterodyne radio frequency receiver designed in the future is improved.

The invention relates to a terahertz quasi-optical power combining and amplifying device and is applied to power combination and amplification of a terahertz frequency band. The device comprises a microwave transmission horn antenna, a dielectric lens A, a microwave amplification array chip, a terahertz frequency-doubling array chip, a dielectric lens B and a terahertz horn reception antenna. According to the focusing effect of the dielectric lens A, spherical electromagnetic wave signals input by the microwave transmission horn antenna are converted into plane wave signals which are transmitted to the microwave amplification array chip to realize amplification and output. Amplified microwave signals are transmitted to the terahertz frequency-doubling array chip to realize frequency doubling and output. The frequency-doubling terahertz signals combine into high-power signals through the dielectric lens B in the form of quasi-optical wave beams, thereby realizing coupling and matching with the terahertz horn reception antenna. The high-power terahertz signals can be outputted by adopting a quasi-optical power combining structure, thus the terahertz quasi-optical power combining and amplifying device is simple in structure and convenient to debug.

The invention discloses an L-waveband broadband dual-polarization short-backfire dipole antenna which is composed of four radiators, two coaxial feed lines, two metal Balun support columns, two horizontal problems an improved hexagonal reflection back cavity, a fixed disck and a hexagonal matching disk. The invention uses the improved hexagonal reflection back cavity to reduce mutual coupling among units, improve the bandwidth and enhance the axial gain. The antenna is characterized in that radiation directional diagram are symmetrical rotationally, the cross polarization level is low, the reflection loss is low and the like; and can serve as a composition unit in the front end of a receiver of an antenna phased array feed source of an L-waveband radio astronomy telescope, as well as a phased array feed source for a communication, measurement and control and reflection plane monitoring antenna.

The invention disclose a double-notch ultra-wideband antenna, which comprises a dielectric substrate (1), a radiating element (2), a coplanar metal grounding plate (3), and a microstrip feeder (4), wherein double T-shaped filters (22, 23) are introduced onto the radiating element (2), rectangular complementary split-ring resonator (CSRR) structure grooves (31, 32) are formed in the grounding plate (3), the radiating element (2) is arranged on the upper middle part of the dielectric substrate (1), the microstrip feeder (4) is led to the radiating element (2) from the lower edge of the dielectric substrate (1) and is connected with the radiating element (2), and the grounding plate (3) is composed of two unfilled-corner rectangular metal plates which are positioned on two sides of the microstrip feeder (4) and equal in distances to the microstrip feeder (4). The double-notch ultra-wideband antenna adopts a coplanar waveguide feeding method, realizes ultra wideband by utilizing oval-like patches, and realizes notch features at the WiMAX (3.3-3.7GHz) and WLAN (5.15- 5.825GHz) frequency bands by utilizing the double T-shaped filters (22, 23), the grounding plate and the rectangular complementary split-ring resonator structure grooves. The double-notch ultra-wideband antenna can effectively reduce the mutual interference among the ultra-wideband system, the WLAN system and the WiMAX system, and realizes cooperative communication.

The invention discloses a broadband channelized transceiver which comprises a radio frequency transceiver module, a channel frequency conversion module, an intermediate frequency transceiver module and a control module.The device utilizes the radio frequency transceiver module, the channel frequency conversion module, the intermediate frequency transceiver module and the control module which are sequentially connected.When receiving the signal, the radio frequency signal received by the radio frequency transceiver module is divided into radio frequency signals of different working frequency bands by the channel frequency conversion module and is mixed and sentto the intermediate frequency transceiver module;and an effective intermediate frequency geophone channel is judged by a control module according to a detection signal sent by a plurality of intermediate frequency geophones and a preset threshold value, at the same time, corresponding control signals are generated for SPMT IF switches. The IF transceiver module controls the opening and closing of SPMT IF switch according to the control signal of the control module to realize the signal input or output of the corresponding IF power divider, and realizes the signal transceiver mode of wideband RF input, narrowband IF output, narrowband IF input and wideband RF output.

The invention discloses a millimeter wave adjustable filter. A millimeter wave filter structure can comprehensively consider low loss, rapid debugging, high Q values and miniaturization of the filter,sensitivity and the dynamic range of a system can be remarkably improved, and millimeter wave transceiving system performance is greatly improved. The millimeter wave filter structure comprises an upper substrate, a lower substrate and a metal carrier, a millimeter wave filter inverted micro-strip circuit is arranged on the upper substrate, a liquid crystal cavity is formed in the center of the lower substrate and filled with liquid crystal, feed lines electrically connected with the liquid crystal are arranged on two sides of the liquid crystal cavity, the upper substrate, the lower substrate and the metal carrier are sequentially arranged from top to bottom, a micro-strip metal wire in the millimeter wave filter inverted micro-strip circuit and the liquid crystal are closely combined, and a liquid crystal injection hole communicated with the liquid crystal cavity is formed in the upper substrate. The millimeter wave filter structure has good frequency reconfigurable characteristics.

The invention provides a four-band terahertz absorber with independently and continuously adjustable amplitude and frequency. The device relates to the technical field of metamaterial and terahertz wave application. The main structure of the device comprises a dielectric substrate, a metal reflecting plate in the upper surface of the dielectric substrate, a dielectric substrate in the upper surface of the metal reflecting plate, and a composite resonance structure array in the upper surface of the dielectric substrate. Tunable materials of indium antimonide and photosensitive silicon are used,and the frequencies of four absorption frequency points are tuned by controlling the external temperature; the intensity of an external pump light source is controlled, the amplitudes of the four absorption frequency points are regulated and controlled, the effect that the amplitude and the frequency of an absorption peak are independently and continuously adjustable is achieved, and the workingfrequency band of the terahertz absorber is broadened. The four-band terahertz absorber has the advantages of strong functionality, insensitive polarization, simple structural design, strong practicability and the like.

The invention discloses a terminal antenna frequency band extension structure comprising a metal rear cover and a metal middle frame. The metal middle frame is arranged around the metal rear cover. The bottom part of the metal middle frame is provided with two broken seams. The metal middle frame arranged between the two broken seams acts as an antenna radiator. The antenna radiator is provided with a feed point, a grounding point and a metal middle frame wire which is connected with the broken seams. The low frequency band bandwidth and the high frequency band bandwidth generated by the antenna radiator through resonance can be adjusted through the metal middle frame wire. The terminal antenna frequency band extension structure also comprises a metal coupling sheet which is arranged at the tail end of the antenna radiator and positioned at the target position around the grounding point. The metal coupling sheet is connected with the metal radiator through a metal shorting pin so as to extend the low frequency band bandwidth or the high frequency band bandwidth through coupling between the metal coupling sheet and the antenna radiator, wherein the metal coupling sheet is parallel to the bottom part of the metal rear cover.

The invention discloses a broadband IPD balun chip integrating impedance matching and band-pass filtering functions, and belongs to the field of microwave transmission and the field of integrated circuits. The broadband IPD balun chip takes a GaAs material as a substrate, and MIM capacitors and spiral inductors grow on the substrate. The broadband IPD balun chip comprises an input port and two output ports, wherein the input port is connected with the first spiral inductor through a transmission line and is connected with the first MIN capacitor in parallel at the same time; the first spiral inductor is connected with the second spiral inductor through an air bridge structure, the second spiral inductor is connected with a first coupling inductor and the second MIN capacitor, the first coupling inductor is connected with the first output port and is connected with the second coupling inductor at the same time, and the second coupling inductor is connected with the third MIN capacitor and the second output port. The broadband IPD balun chip has the characteristics of microminiaturization, integration, good band-pass characteristic, low insertion loss and broad band.

The invention relates to the technical field of integrated circuit design and manufacture, in particular to a single chip power amplifier which is widely used for various kinds of active radar components of W wave band millimeter waves and communication systems. An input match circuit is integrated on a single chip, the input end of the input match circuit is connected with an external signal input source, the output end of the input match source is sequentially connected with a four-level transistor amplifier, an output match circuit and a power synthesis circuit in series and then outputs outside, wherein the four-level transistor amplifier comprises a first level transistor amplifier, a second level transistor amplifier, a third level transistor amplifier, and a fourth level transistor amplifier. The single chip power amplifier can be widely used for the fields of various kinds of active radar components of W wave band and millimeter wave communication systems. The single chip power amplifier has the advantages of being wide in working frequency range, stable in full frequency range property, and capable of effectively decreasing an area of a chip and loss, and achieving high power output of the chip.

The invention discloses an antenna system, comprising a substrate, and a plurality of antenna units which are arranged in a predetermined geometric pattern and are connected to the substrate. Each antenna unit includes a horizontally polarized antenna and a vertically polarized antenna. The horizontally polarized antenna or the vertically polarized antenna of the antenna unit is stimulated based on instruction and the antenna type signal adopting the antenna system, and thereby better wireless link can be provided to the communication device.

The invention discloses an electromagnetic-wave absorbing material with the interstitial modulation characteristics and a production method of the electromagnetic-wave absorbing material. The general formula of the electromagnetic-wave absorbing material is R<2>Fe<17>N<x>C<y>, wherein the R refers to combination of any one or multiple rare earth elements of Y, Ce, Nd, Pr, Sm, Gd, Tb, Dy, Ho, Er, Tm and Lu, the x and the y respectively refer to nitrogen and carbon content entering the lattice gap position, 0< / =<x>+<y>< / =9, and the x and the y are not equal to 0 at the same time; the electromagnetic-wave absorbing material is an R<2>Fe<17>-type master alloy billet formed by mixing and melting the rare earth element R and an iron element and is obtained by subjecting the master alloy billet coarse crushing prior to being introduced into clearance carbon atoms and / or nitrogen atoms to have magnetism of a master alloy crystal modulated. The electromagnetic-wave absorbing material has high absorbing capability on high-frequency electromagnetic waves ranging from 1GHz to 100GHz in smaller matching thickness, and the characteristics of accurate operation frequency modulation can be realized by the production method and according to different use conditions.

The invention discloses a terminal antenna frequency band extension structure comprising a metal rear cover and a metal middle frame. The metal middle frame is arranged around the metal rear cover, and the metal rear cover and the metal middle frame form an integrated structure. The two ends of the integrated structure are provided with seams. The integrated structure is separated into two antenna radiators and a back metal plate by the seams. The two antenna radiators are respectively provided with a first grounding point, a feed point and a second grounding point. The antenna radiators are enabled to generate low frequency band bandwidth and high frequency band bandwidth through resonance by controlling disconnection and connection of the two first grounding points. The terminal antenna frequency band extension structure also comprises metal coupling sheets which are arranged at the target positions around the feed points so as to extend the low frequency band bandwidth or the high frequency band bandwidth through coupling between the metal coupling sheets and the antenna radiators, wherein the metal coupling sheets are parallel to the top part or the bottom part of the metal rear cover.

The invention belongs to the technical field of testing, and relates to an impedance adjuster used for multi-parameter measurement of a microwave network under a microwave large signal state. The whole machine of the impedance adjuster consists of a microwave main body, a control unit, a display unit, a key, a drive unit, a photoelectric detection feedback unit, an external control computer, a standard external control interface and a precision The mechanical transmission part is composed. According to the principle of adjusting impedance in parallel, the impedance adjuster is connected in parallel to the flat coaxial transmission line through the admittance slider. The automatic control based on the high-performance microprocessor cooperates with the precision stepping motor and the precision mechanical transmission device, which can accurately realize the The displacement control of the admittance slider completes precise and small controlled displacement in the horizontal and vertical directions, and realizes precise impedance adjustment with a maximum reflection coefficient modulus of 0.875 and a repeatability better than 40dB.

The invention discloses a terminal antenna frequency band expansion structure, which comprises a metal back cover, a metal middle frame and a metal coupling piece. The metal back cover is peripherally provided with the metal middle frame. The metal back cover is separated with the top portion or the bottom portion of the metal middle frame through a gap to enable the top portion or the bottom portion of the metal middle frame to serve as an antenna radiation body, wherein the antenna radiation body is connected with a grounding point at a first position, is connected with a feeding point through an adjustable capacitor at a second position and is connected with a tuning circuit through a multipath tuning switch at a third position; and the metal coupling piece is arranged at the place of a target position around the feeding point to expand bandwidth of the antenna radiation body through coupling between the metal coupling piece and the antenna radiation body.

The invention discloses a channel loaded bow-tie electromagnetic band gap antenna which comprises an electromagnetic band gap structure. The antenna is characterized in that: the bow-tie antenna is supported by a supporting layer and is arranged on the electromagnetic band gap structure; one end of a Balun is connected with the bow-tie antenna to feed current to the bow-tie antenna by passing through a through hole arranged in the center of a substrate of the electromagnetic band gap structure, and the other end is connected with an SMA. In the antenna, capacitive load and inductive load can realize self-balance in broad frequency band, and the impedance and the radiation mode in the antenna are stable, thus expanding the impedance bandwidth of the antenna; and the antenna gain is not affected while expanding the operation bandwidth of the antenna; the distance between the antenna and the electromagnetic band gap structure can be rather less than a quarter wavelength, and broad operating frequency range and good gain can be acquired.