206 results about "Varicap" patented technology

The invention relates to a reconfigurable dual-mode leaky-wave antenna with global scanning capability and a reconfiguration method, the leaky-wave antenna comprises a double-layer slow-wave waveguide structure formed by an upper metal conductor and a lower metal conductor, and the upper metal conductor and the lower metal conductor are separated by a dielectric substrate; the double-layer slow-wave waveguide structure comprises a plurality of periodic units, and a plurality of T-shaped structures with opposite directions are processed on upper and lower layers of metal conductors of each periodic unit to form a plurality of grooves; a variable capacitance diode is embedded into the tail end of a slot arm of the upper-layer metal conductor and is electrically connected with the lower-layer metal conductor through a metal via hole, and a closed loop is formed between the upper-layer metal conductor and the lower-layer metal conductor; a plurality of elliptical radiation patches are arranged at the top of a slot arm of the lower metal conductor at intervals and used for radiation leakage of the slow wave waveguide, and continuous frequency scanning covering 180 degrees is achieved; according to the invention, two modes of frequency scanning and fixed-frequency scanning are fused, 180-degree global scanning can be realized in any frequency reconfigurable interval, and beams can be flexibly reconstructed through multiple control strategies under a fixed-frequency condition.

The invention provides a frequency, polarization and directional diagram reconfigurable antenna unit and array. The antenna unit comprises a tuning microstrip antenna unit and a reconfigurable feed phase-shift network which are stacked, the tuning microstrip antenna unit comprises a circular radiation patch etched with a circular gap and four variable capacitance diodes bridged on the circular gap; two output ports of a Wilkinson power division network in the reconfigurable feed phase shift network are respectively connected with two feed point micro-strips through PIN diodes, and four feed points form a structure which is in space symmetry and asymmetric in impedance. The circular radiation patch and the annular radiation patch in the antenna unit have continuity in structure, only four variable capacitance diodes are loaded on the annular gap, gain fluctuation is reduced, and the antenna unit is fed through four feed points which are symmetrical in space and asymmetric in impedance, so that the antenna unit is more stable in performance. Good matching can be kept between the feed phase-shifting network and the antenna unit in a broadband range, and the tuning bandwidth of the antenna is widened.

The invention discloses a linear polarization scattering reconfigurable array antenna, which belongs to the technical field of antenna manufacturing and comprises an antenna unit, an extension socket, a transmission type phase shifter and an inductor. The antenna unit comprises a radiation patch, a first dielectric substrate, a metal via hole, a metal patch, a second dielectric substrate, a perforated metal floor, a third dielectric substrate, a feed metal column and a radio frequency coaxial connector, the radio frequency coaxial connector is connected with the radiation patch through the feed metal column, and a variable capacitance diode and a capacitor are arranged on the transmission type phase shifter. The transmission type phase shifter is connected with the radiation patch through the feed metal column, the variable capacitance diode is connected with the punching metal floor, the bottom of the third dielectric substrate is provided with a direct current bias line, the direct current bias line is connected with the transmission type phase shifter through the inductor, and the transmission type phase shifter is connected with the radiation patch through the feed metal column. According to the invention, flexible regulation and control of antenna scattering beams can be realized, and the antenna has the characteristics of flexible control, fast response speed and high radiation efficiency.

This disclosure relates generally to a composite reconfigurable intelligent surface system for real time beam steering and method thereof. Conventional method for real time beam steering includes bulky systems with several antenna elements and amplifiers to shape and control the beam. The present disclosure provides a composite reconfigurable intelligent surface (CRIS) for real time beam steering. The CRIS is formed from a set of constituent reflecting surfaces which in turn are generated from unit cells. These unit cells are responsible for providing individual phase reflection performance utilizing the installed varactor diode in each unit cell. The CRIS can provide a) multi-beam reflection performance, b) polarization sensitive operation, c) 2D beam steering abilities, d) real-time beam control, e) null point reduction for beam shaping requirements and f) dependable pattern stability over a suitable range of frequencies.

The invention discloses a band-pass type active frequency selective surface based on double-element composite loading. The band-pass type active frequency selective surface comprises at least one resonance unit which is periodically arranged, the resonance unit sequentially comprises a top metal frequency selection surface layer, a first dielectric structure layer, a middle metal feed layer, a second dielectric structure layer and a bottom metal frequency selection surface layer from top to bottom; the top metal layer and the bottom metal layer are composed of square ring aperture grooves subjected to deformation processing, and the middle feed layer is of a cross zigzag metal structure, plays a role in coupling an electromagnetic field and serves as a bias network of the AFSS. And the metal through holes penetrate through the resonance units in the vertical direction, so that the middle layer feeder line can respectively provide reverse bias voltage for independently regulating and controlling the resonance frequency for the PINs and the variable capacitance diodes on the top layer and the bottom layer. According to the invention, the functions of band switching and wide-range frequency tuning can be met, so that the problem of insertion loss increase caused by limited design frequency regulation and control range and element loading of the AFSS in the prior art can be solved.

A reconfigurable metasurface sub reflector comprises an array of cell units. Each sub unit is formed of two sub-unit cells formed with at least two conducting layers separated by a dielectric substrate. One conducting layer has, in each of the sub-unit cells, two parallel strips connected by a varactor and the other conducting layer serves as a ground layer. Setting the reverse biasing for each of the varactors controls the azimuth and elevation of reflection from the reconfigurable metasurface sub reflector.

The invention discloses a broadband circularly polarized scattering reconfigurable array antenna based on variable capacitance diode loading, and the broadband circularly polarized scattering reconfigurable array antenna is composed of a plurality of scattering reconfigurable antenna units. The scattering reconfigurable antenna unit comprises a resonance structure used for radiating or receiving signals and a feed and phase shift structure arranged on the lower surface of the resonance structure. The feed and phase shift structure comprises a broadband directional coupler and a reflection type broadband phase shifter. When the scattering reconfigurable antenna unit is in a radiation working state, the broadband directional coupler radiates energy to the resonant structure; when the scattering reconfigurable antenna unit is in a scattering working state, the broadband directional coupler transmits energy to the reflection type broadband phase shifter, and the reflection type broadband phase shifter regulates energy of secondary radiation of the reflection type broadband phase shifter according to bias voltage applied to an internal variable capacitance diode. The array antenna provided by the invention is wide in working frequency band, and the radiation performance can be ensured while the scattering characteristic is reconfigurable.

A radio frequency communication filter based on voltage tuning comprises an LC low-pass filter composed of a first set of parallel variable capacitance diode units, a second set of parallel variable capacitance diode units and an inductor L2, and an RC high-pass filter which is adjusted along with a tuning voltage control end VT and composed of a capacitor C2, a variable capacitance diode V17, a variable capacitance diode V18, a capacitor C4 and a resistor R2. A third group of parallel variable capacitance diode units, a fourth group of parallel variable capacitance diode units and an inductor L3 form an LC low-pass filter, and a capacitor C3, a variable capacitance diode V20, a variable capacitance diode V19, a capacitor C5 and a resistor R2 form another RC high-pass filter which is adjusted along with a tuning voltage control end VT. And the two band-pass filters are connected to form a high-selectivity and low-insertion-loss adjustable band-pass filter driven by the same controllable tuning voltage control end.

A phase shifter including a 90 degree hybrid circuit having two reflection ends, a varactor having a variable capacitance layer made of vanadium dioxide and disposed at the reflection end of the 90 degree hybrid circuit, and a stub connected to the reflection end of the 90 degree hybrid circuit via the varactor.

A nonlinear transmission line (NLTL) comprises a plurality of interconnected transmission line cells, each including a shunt path and a transmission line length wherein the shunt path includes a varactor diode and an inductor coupled in series with the varactor diode. A shunt path transmission line may be coupled in the shunt path and one or more filters may be coupled to an input and / or an output of the NLTL.

The invention provides a wave-transparent band frequency-adjustable frequency selection surface, which comprises a loss layer, a frequency selection layer and a bias network, the loss layer and the frequency selection layer are periodically arranged, the loss layer comprises a first resonant structure and a second resonant structure, and the frequency selection layer comprises a third resonant structure. The upper bias network and the lower bias network are respectively connected with direct-current voltages with different polarities, so that the variable capacitance diodes in the first resonant structure and the third resonant structure work under different voltages to generate different capacitance values, the resonant frequency point of the loss layer and the resonant frequency point of the frequency selection layer in the structures generate frequency shift at the same time, and finally continuous adjustability in the wave-transparent frequency band of 5.51 GHz to 6.31 GHz is achieved. Under the action of the second resonant structure and other lumped resistors of the loss layer, wave absorption within the frequency band range of 4.31 GHz to 5.15 GHz and the frequency band range of 6.31 GHz to 13.81 GHz is achieved. The device has the characteristics of continuous frequency modulation and out-of-band wave absorption, can effectively suppress interference of outside electromagnetic waves in other frequency bands or electromagnetic waves in a frequency band close to a communication frequency band on communication, can reduce the radar cross section of a target, and is beneficial to target stealth.

The invention provides a metamaterial reconfigurable dual-polarized antenna array and a dynamic beam forming method thereof. The dual-polarized antenna array is composed of a metamaterial resonance unit array, a reconfigurable polarization network, an intelligent control unit and an adaptive beam forming algorithm. The metamaterial unit structure with the dual-polarization characteristic is designed, and continuous adjustment of the polarization state and the radiation characteristic is achieved by integrating the liquid metal microchannel and the variable capacitance diode. A hierarchical control framework and a deep reinforcement learning algorithm are adopted, self-adaptive optimization control over an antenna array is achieved, and the characteristics of high-precision beam forming, quick response and high energy efficiency are provided while low system complexity is kept. Flexible regulation and control of the polarization state, high-precision beam forming, low system complexity, quick response, high energy efficiency and wide dynamic range can be realized at the same time, so that the requirement of a future communication system on a high-performance antenna is met.

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

The utility model discloses an intelligent metasurface wireless communication system based on radar assistance. The intelligent metasurface wireless communication system comprises a radar, a controller, a voltage control module and an intelligent metasurface structure which are connected in sequence. The controller is used for receiving position information detected by the radar and converting the position information into a bias voltage coding sequence; the voltage control module is used for outputting bias voltage to the intelligent metasurface according to the bias voltage coding sequence; the intelligent metasurface comprises a plurality of metasurface units arranged in an array, each metasurface unit comprises a variable capacitance diode, and the variable capacitance diodes are driven by the bias voltage to realize dynamic beam tracking. The wireless communication system provided by the utility model not only can improve the capability and stability of wireless communication between the base station and the target and enlarge the wireless coverage range of the base station, but also can be used in various illumination conditions such as heavy fog, night and the like and various wireless communication scenes such as urban traffic scenes, indoor scenes and the like.

This application discloses an intelligent reflective surface and a covert communication system, belonging to the field of wireless communication technology. The intelligent reflective surface includes multiple intelligent reflective surface units arranged in an array; each intelligent reflective surface unit includes: a first substrate, a second substrate, and a third substrate; a metal patch and a varactor diode, located on the side of the third substrate opposite to the second substrate; the metal patch includes a first patch and a second patch, and the varactor diode is located between the first patch and the second patch, with its negative and positive terminals electrically connected to the first patch and the second patch, respectively; a metal ground plane, located between the first substrate and the second substrate; a first bias line and a second bias line, located on the side of the first substrate opposite to the second substrate; the first bias line is electrically connected to the metal ground plane and the first patch, respectively, and the second bias line is electrically connected to the second patch. This application can achieve precise control of electromagnetic waves, reduce electromagnetic energy loss, improve energy transmission efficiency, suppress electromagnetic wave leakage, and improve communication covertness.

The application discloses a variable-beam control method of a variable capacitance diode-based element grating leaky-wave antenna, and comprises the following steps: S1, researching and analyzing an ultra-grating beam conversion mechanism; researching the mechanism of a planar ultra-grating under anisotropic, uniform and continuous periodic boundary conditions; S2, according to the ultra-grating, researching a transmission mode and optimization design of a Floquet-Bloch theorem; researching an FB mode, and eliminating the bad FB mode by designing a tool for ultra-grating parameters; S3, analyzing and designing the ultra-grating leaky-wave antenna; researching the analytical field and current of the synthesized ultra-grating in the framework of the leaky-wave antenna, so as to customize the performance of phase, beam shape and polarization; S4, designing and analyzing an electrically-tuned beam control ultra-grating leaky-wave antenna; the application adopts the variable-beam control method of the variable capacitance diode-based element grating leaky-wave antenna, adopts a simple structure of a tunable material to tune an efficient structure platform, and lays a road for a new generation of efficient special gratings.

The invention provides a layout pattern of a semiconductor varactor, which comprises a plurality of varactor units arranged on a substrate, wherein each varactor unit comprises a plurality of fin structures arranged in parallel with each other, a plurality of gate structures arranged in parallel with each other, located on the substrate and spanning the fin structures, and a gate metal layer electrically connected with the plurality of gate structures.

The application discloses an implementation device and method of a controllable nonreciprocal circuit, and the device comprises a vector network analyzer, a left coupling capacitor, a right coupling capacitor and a nonlinear LC resonant cavity, wherein the resonant frequency of the nonlinear LC resonant cavity is jointly regulated by a direct current bias voltage loaded on a varactor diode and a microwave signal. The application utilizes the difference in coupling efficiency of microwave energy coupled into the nonlinear LC resonant cavity when the microwave signal is transmitted forward and reversely, and utilizes the regulation of the direct current bias voltage on the nonlinear interaction between the microwave signal and the LC resonant cavity mode in the nonlinear LC resonant cavity, so that the nonlinear LC resonant cavity can be in different bistable states when the microwave signal is transmitted forward and reversely, and thus the controllable nonreciprocal transmission with high contrast can be realized for the microwave signal in a larger working bandwidth.

The application discloses a SAR two-dimensional multi-phase segmented modulation interference method based on time modulation metasurface, and relates to the technical field of signal processing. In the application, each metasurface unit is combined with two open reverse and symmetrical metal square rings and varactor diodes, so that the phase, amplitude and polarization state of the incident electromagnetic wave are flexibly regulated and controlled. The dynamic regulation and control capability enables the metasurface to adjust the response to the electromagnetic wave in real time according to the requirements of different application scenarios, so that the electromagnetic environment is accurately controlled. The structure of the application only uses two open reverse and symmetrical metal square rings and varactor diodes, so that the phase, amplitude and polarization state of the incident electromagnetic wave are flexibly regulated and controlled, and the electromagnetic environment is accurately controlled. Compared with the traditional complex time modulation metasurface, the modulation performance of the time modulation metasurface is greatly improved, and high-precision SAR radar interference is realized.

The present invention discloses a non-magnetic simultaneous transmit and receive (STAR) duplexer for terahertz communication and sensing integration, which includes a dielectric substrate, a microstrip stepped impedance filter, varactor diodes, terahertz signal input / output ports, modulation signal input ports, ground ports, and a Y-shaped microstrip transmission line connection. Through the design of distributed parameter circuits, the present invention overcomes the problem of mismatch of the non-magnetic STAR duplexer with lumped parameter circuits at high frequencies. The main structure of the present invention is composed of a microstrip circuit. The ports connecting the external modulation signal and the ground port include lumped element filters. The overall structure is simple and easy to process and integrate.

The application discloses a multi-mode absorbing frequency selective surface with adjustable wave absorbing capacity, which comprises a metal pattern layer, a first dielectric substrate, a metal back plate, a second dielectric substrate and a metal feed line layer arranged in sequence from top to bottom, wherein the metal pattern layer comprises a plurality of metal unit structures arranged in an array, each metal unit structure comprises a polygonal metal sheet located at the center of the unit, metal bands extending from the periphery of the polygonal metal sheet, and metal arms extending from the four corners of the unit, the metal arms comprise two independent metal structures, the polygonal metal sheet and the metal bands are connected to each other through a first varactor diode, the two independent metal structures are connected to each other through a second varactor diode, and the metal arms in adjacent metal unit structures jointly form a new rotating cross structure. The independent feed line network is built through the metal through hole, so that the structure is divided into two independently regulated parts, and the whole has single and double adjustable wave absorbing modes.

This invention relates to a pattern-reconfigurable antenna based on artificial surface plasmon polaritons (SSPPs), belonging to the field of antenna technology. The antenna includes a coplanar waveguide feed line, a transition structure, a reconfigurable SSPP waveguide, and periodic radiating elements. The reconfigurable SSPP waveguide modifies the dispersion characteristics by adding a varactor diode to a traditional SSPP element and adjusting the capacitance value using a bias circuit. The periodic radiating elements are elliptical patches with rectangular slots, coupled to the reconfigurable SSPP waveguide to radiate electromagnetic waves. This invention solves the problems of single radiation direction in traditional antennas and low gain in existing reconfigurable antennas. It achieves fixed-frequency beam scanning (maximum 23°) and frequency beam scanning (maximum 90°) in the 11.5GHz-15GHz frequency band, with gains greater than 9dBi (maximum 11.1dBi), expanding the detection range and increasing the detection distance, making it suitable for fields such as UAV detection.

The invention belongs to the technical field of filters, and particularly relates to a reconfigurable electric tuning frequency hopping filter and a multi-target optimization control method thereof.The filter comprises an MCU module, a resonance circuit module, a pre-distortion module and a signal receiving and transmitting module, the MCU module is provided with two main control CPUs and used for radio frequency signal processing, parameter control and communication coordination, address codes are calculated through the main control CPUs, and the signal receiving and transmitting module is used for receiving and transmitting signals. Radio frequency signal processing is set to be straight-through processing or filtering processing, a C-V curve and tuning voltage-frequency response of a variable capacitance diode are measured, a nonlinear model is established, and the non-linear model is used for radio frequency signal preprocessing of the MCU module, sending the radio frequency signal to the pre-distortion module or outputting the radio frequency signal after straight-through processing through parameter control of the MCU module. According to the invention, non-linear compensation can be carried out on signals with different frequencies in advance, and then the signals are distributed to corresponding resonance circuits through a digital chip in an address code calculation mode, so that the out-of-band rejection performance is improved, and distortion is reduced.

A varactor-tunable radio frequency (RF) resonant circuit is disclosed. The circuit includes a planar impedance-controlled transmission line disposed on a dielectric substrate, and a voltage-controlled varactor diode, or an arrangement of parallel varactor diodes, electrically connecting a resonator of the planar transmission line to a reference node. The resonator can have a stepped impedance. A frequency of the resonator is tunable by configuration of a reverse bias voltage applied to the first plurality of voltage-controlled varactor diodes.

The application discloses a double-passband low-frequency passband independently tunable frequency selective surface, metal columns pass through cross structure metal layers to connect upper and lower double-passband metal layers, form a multilayer cascade structure to expand bandwidth and adjust characteristics in the passband, the upper and lower double-passband metal layers include an outer metal frame and four branches in the outer metal frame, a variable capacitance diode is arranged on each branch, the side of the branch extends to the outer metal frame and / or the outer metal frame extends to the side of the branch to form a first gap; when direct current is fed through the metal columns, the variable capacitance diode provides a first capacitance, the first gap provides a second capacitance, the first capacitance is greater than the second capacitance, the first capacitance is used for controlling a low-frequency passband, and the second capacitance is used for controlling a high-frequency passband; when different direct currents are applied to the two ends of the variable capacitance diode, the low-frequency passband is moved, the high-frequency passband remains unchanged, and independent tuning of the low-frequency passband is realized.

Embodiments herein disclose an inductor-capacitor voltage controlled oscillator (LC-VCO) circuit. The LC-VCO circuit includes: an LC tank circuit including a center tap inductor connected in parallel with a capacitor bank without a varactor, where the LC tank circuit resonates to generate an oscillation voltage; and a control circuit connected to a varistor capacitance circuit, where the varistor capacitance circuit includes a varistor based on a voltage controlled transistor in series with at least one capacitor, the varistor capacitance circuit is connected in parallel with the LC tank circuit and connected to a negative transconductance circuit. The control circuit includes an error amplifier and a conversion circuit, and is configured to generate an output control voltage based on an input phase-locked loop (PLL) control voltage that controls a capacitance value of the varistor capacitance circuit through the variable resistor.

Described herein are switches with asymmetrical anti-series varactor pairs to improve switching performance. The disclosed switches can include asymmetrical varactor pairs to reduce distortions. The asymmetry in the varactor pairs can be associated with geometry of each varactor in the pair. The disclosed switches can stack both symmetrical and asymmetrical varactor pairs. The disclosed switches with asymmetrical anti-series varactor pairs can be configured to improve both H2 and H3 simultaneously.

The invention discloses a frequency reconfigurable conformal array antenna and a preparation method thereof, an antenna metal radiation layer comprises a power distribution network and a reconfigurable antenna unit, a main radiation patch of the reconfigurable antenna unit is a rectangular metal patch, feed is carried out in a side feed mode, and the main radiation patch is a rectangular metal patch. The variable capacitance diode is arranged in the middle of the U-shaped groove between the main radiation patch and the parasitic patch; the 4 * 4 equidistantly arranged reconfigurable antenna units are connected with the T-junction power divider, and the input port of the power divider is connected with an external direct current bias device. By controlling the external bias voltage, the junction capacitance of the variable capacitance diode can be changed, and the reconstruction of the current on the surface of the patch is realized, so that the reconfigurable frequency is realized. The invention also discloses a processing method of the antenna. The antenna disclosed by the invention has the characteristics of low profile, simple structure, low cost, continuously reconfigurable frequency and the like, and the conformal preparation of the antenna can be realized according to the preparation scheme, so that the antenna has a conformal characteristic, and the influence of the antenna on the aerodynamic configuration of a carrier is reduced.

Design and control techniques for passive multiple-input multiple-output (pMIMO) surfaces are provided. An example reconfigurable reflective element array includes a plurality of unit cells each including a cross-slot radiating element, a first varactor disposed across a first end of the cross-slot radiating element and configured to control polarization in a first plane, and a second varactor disposed across a second end of the cross-slot radiating element and configured to control polarization in a second plane. And a second varactor disposed across a second end of the cross-slot radiating element and configured to control polarization in a second plane; and a controller coupled to the first varactor and the second varactor and configured to provide a control signal to the first varactor and the second varactor to change a direction of the reflected signal.

The invention discloses an adjustable low-pass filter circuit which comprises two first defected ground structures, two second defected ground structures, two first additional defected ground structures and two second additional defected ground structures which are symmetrically distributed relative to an X axis and are sequentially etched along the Y axis at the position, under a micro-strip transmission line, on a ground plane, and the two first defected ground structures, the two second defected ground structures, the two first additional defected ground structures and the two second additional defected ground structures are symmetrically distributed relative to the X axis. The first defected ground structure is connected with the first direct current bias circuit, and the second defected ground structure is connected with the second direct current bias circuit; variable capacitance diodes are inserted into the first defected ground structure and the second defected ground structure, the sizes of introduced equivalent capacitance and equivalent inductance are changed by changing the sizes of the defected ground structures and the additional defected ground structures, the transmission characteristics of the microstrip transmission line are changed, and the transmission characteristics of the microstrip transmission line are changed by changing the bias voltage of the direct-current bias circuit. The equivalent capacitance of the variable capacitance diode is changed, and the cut-off frequency of the low-pass filter circuit is tuned; the filter has the advantages that high selectivity of the filter is guaranteed, and meanwhile high stopband suppression is taken into consideration.