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CN-121983794-A - Notch reconfigurable ultra-wideband antenna for cognitive radio

CN121983794ACN 121983794 ACN121983794 ACN 121983794ACN-121983794-A

Abstract

The invention discloses a notch reconfigurable ultra-wideband antenna for cognitive radio, and belongs to the technical field of wireless communication and antenna design. The antenna comprises a dielectric substrate, wherein a main radiation patch, a microstrip feeder line and a notch structure patch are arranged on the front surface of the substrate, a floor with a defective ground structure is arranged on the back surface of the substrate, a miniature stepping motor system is further arranged, copper columns are embedded into longitudinal through grooves of the notch structure patch in a clearance fit mode, the motor drives the copper columns to linearly slide, inductance and capacitance parameters of a resonant circuit are changed, a tunable vibration circuit is constructed, the main radiation patch optimizes ultra-wideband impedance matching, the defective ground structure expands high-frequency bandwidth, continuous reconstruction of the notch center frequency of 4.2-7.45GHz can be achieved, and relevant electromagnetic interference is accurately restrained. The invention realizes zero static power consumption through physical displacement tuning, has high linearity and strong robustness, and has higher practical value in the fields of cognitive radio, short-distance communication and the like.

Inventors

  • LIN HAN
  • Tu Rongjiaxu
  • WANG ZHONGGEN

Assignees

  • 安徽理工大学

Dates

Publication Date
20260505
Application Date
20260311

Claims (9)

  1. 1. The notch reconfigurable ultra-wideband antenna for the cognitive radio comprises a rectangular dielectric substrate (1) and is characterized in that a main radiation patch (2), a microstrip feeder (8) and a notch structure patch (3) are arranged on the front side of the dielectric substrate (1), the microstrip feeder (8) is arranged at the side edge of the front side of the dielectric substrate (1), is connected with the main radiation patch (2) and feeds the main radiation patch (2), a floor (4) with a defected ground structure is arranged on the back side of the dielectric substrate (1), the antenna further comprises a micro stepping motor system (5), a longitudinal through groove is formed in the notch structure patch (3), copper columns (11) are adaptively embedded in the longitudinal through groove and can linearly slide along the through groove, and the micro stepping motor system (5) drives the copper columns (11) to generate physical displacement in the longitudinal through groove so as to realize dynamic tuning of a notch frequency.
  2. 2. The cognitive radio-oriented notch reconfigurable ultra-wideband antenna of claim 1, wherein the notch structure patches (3) are symmetrically distributed on two sides of a microstrip feeder (8), the notch structure patches (3) are formed by combining rectangular slotted U-shaped patches (9) and L-shaped patches (10), and edges of the L-shaped patches (10) are electrically connected with a floor (4) through vertical rectangular metal strips arranged on the side walls of a dielectric substrate (1) so as to inhibit unexpected resonance.
  3. 3. The cognitive radio-oriented notch reconfigurable ultra-wideband antenna of claim 2, wherein the dielectric substrate (1) is made of F4B220, the relative dielectric constant is 2.2, the loss tangent is 0.009, the overall size of the dielectric substrate (1) is 30mm x 25mm x 1.6mm, the main radiation patch (2) is composed of a rectangular ring patch (6) and a central special-shaped branch, the special-shaped branch is a combination of a rectangular strip and a circular patch (7), and the main radiation patch (2) and a microstrip feeder (8) are integrally etched on the front surface of the dielectric substrate (1) and used for optimizing impedance matching in a 3.1-11GHz frequency band.
  4. 4. The cognitive radio-oriented notch reconfigurable ultra-wideband antenna of claim 3, wherein the micro stepping motor system (5) comprises a motor main body (14), a sliding rail (15), a non-metal transmission connecting rod (16) and a movable ring (17), the longitudinal through groove penetrates through a dielectric substrate (1) and a metal layer of the U-shaped patch (9), the motor main body (14) is fixedly connected with a copper column (11) through the non-metal transmission connecting rod (16) and the movable ring (17), the inductance-capacitance parameter of a resonant circuit is changed by controlling the translation position of the copper column (11) in the longitudinal through groove, and the copper column (11) penetrates through the dielectric substrate (1) and is kept in electrical contact with a main radiation patch (2) and a floor (4) to construct the resonant circuit with an adjustable physical position.
  5. 5. The cognitive radio-oriented notch reconfigurable ultra-wideband antenna of claim 4, wherein the copper pillar (11) is in clearance fit with the inner wall of the longitudinal through groove, so that the linear sliding precision of the copper pillar (11) is ensured.
  6. 6. The cognitive radio-oriented notch reconfigurable ultra-wideband antenna of claim 5, wherein the sliding rail (15) supports the linear travel range of the copper pillar (11) to be 0.2mm to 4.7mm, and continuous reconfiguration of the notch center frequency in the range of 4.2-7.45GHz is realized by precisely controlling the displacement of the copper pillar (11) so as to inhibit electromagnetic interference of WiMAX, WLAN and C wave bands.
  7. 7. The notch reconfigurable ultra-wideband antenna for cognitive radio according to claim 6, characterized in that the defected ground structure of the floor (4) consists of a rectangular defected ground structure (12) and a 1/4 circular structure (13) symmetrically cut off at the edge of the floor (4), the radius of the 1/4 circular structure (13) is 5.6mm, and the defected ground structure is used for optimizing impedance matching and exciting a new resonant mode, and expanding the antenna high frequency bandwidth to 11GHz.
  8. 8. The cognitive radio-oriented notch reconfigurable ultra-wideband antenna of claim 7, wherein the micro stepper motor system (5) is installed in a non-radiation hot spot area of the dielectric substrate (1), and the non-metal transmission connecting rod (16) is made of polyvinyl chloride.
  9. 9. The cognitive radio-oriented notch reconfigurable ultra-wideband antenna of claim 8, wherein the main radiating patch (2), the notch structure patch (3) and the floor (4) are all made of copper, and the thickness of the copper layer of the metal component is 0.035mm.

Description

Notch reconfigurable ultra-wideband antenna for cognitive radio Technical Field The invention relates to the technical field of wireless communication and antenna design, in particular to a notch reconfigurable ultra-wideband antenna for cognitive radio. Background In the fields of wireless communication, cognitive radio and complex electromagnetic environment detection, although the traditional ultra-wideband antenna has extremely wide working frequency band, technical limitations which are difficult to avoid are gradually exposed in practical application. For example, in the field of cognitive radio, a system needs to sense an environmental spectrum in real time and dynamically adjust a working state to realize accurate avoidance of interference of an authorized frequency band, and in the field of short-distance communication and radar imaging, UWB equipment needs to work in a wide frequency band of 3.1-10.6GHz so as to ensure high transmission rate and positioning accuracy. However, due to the extremely wide UWB band, spectrum overlap is inevitably generated with narrowband systems such as WiMAX, WLAN, and C-band, resulting in serious electromagnetic interference. Current notch antenna designs have evolved from a single fixed notch to multiple bands, reconfigurable directions. While the conventional fixed notch scheme can suppress interference, as the number of notches increases, the effective bandwidth available to the system is greatly reduced, resulting in a significant drop in spectrum utilization. In order to balance interference suppression and spectral efficiency, a reconfigurable antenna with notch band dynamic tuning capability is the focus of research. The current notch antenna design with reconstruction characteristics cannot meet the cooperative requirements of continuous tuning, high linearity and physical robustness. The method is characterized in that a scheme of a PIN diode or a switching circuit is adopted to realize limited discrete state switching, continuous direct current power consumption can be generated by a complex bias network, the scheme of a varactor diode or a field effect transistor is utilized to improve the adjustment precision, but the scheme often faces the nonlinear effects of limited tuning range, high insertion loss and serious, and the novel reconstruction technology based on liquid metal is limited by a fluid control structure with easily oxidized material, poor long-term stability and complexity. Disclosure of Invention The invention aims to provide a notch reconfigurable ultra-wideband antenna for cognitive radio, which solves the problems of nonlinearity of an active device, discrete state switching and easy oxidization of liquid metal in the prior art, and realizes continuous dynamic tuning of notch center frequency within the range of 4.2-7.45GHz by a mechanism of driving copper columns by a micro stepping motor, thereby providing a radio frequency solution with strong suitability and excellent performance for anti-interference communication under the cognitive radio and complex environment while achieving zero static power consumption, high linearity and strong physical robustness. The invention provides a notch reconfigurable ultra-wideband antenna for cognitive radio, which comprises a rectangular dielectric substrate, wherein a main radiation patch, a microstrip feeder and a notch structure patch are arranged on the front side of the dielectric substrate, the microstrip feeder is arranged on the side edge of the front side of the dielectric substrate, is connected with the main radiation patch and feeds the main radiation patch, a floor with a defected ground structure is arranged on the back side of the dielectric substrate, the antenna further comprises a micro stepping motor system, a longitudinal through groove is formed in the notch structure patch, copper columns are adaptively embedded in the longitudinal through groove and can linearly slide along the through groove, and the micro stepping motor system drives the copper columns to generate physical displacement in the longitudinal through groove so as to realize dynamic tuning of notch frequency. Preferably, the notch structure patches are symmetrically distributed on two sides of the microstrip feeder, the notch structure patches are formed by combining rectangular grooved U-shaped patches and L-shaped patches, and edges of the L-shaped patches are electrically connected with a floor through vertical rectangular metal strips arranged on the side walls of the dielectric substrate and used for inhibiting unexpected resonance. Preferably, the dielectric substrate is made of F4B220, the relative dielectric constant is 2.2, the loss tangent is 0.009, the overall size of the dielectric substrate is 30mm multiplied by 25mm multiplied by 1.6mm, the main radiation patch consists of a rectangular ring patch and a central special-shaped branch, the special-shaped branch is a combination of a rectangular strip