A kind of double mode beam direction switchable antenna
Technical field
The invention belongs to electronic technology field, particularly with the beam direction switchable antenna technology of pin diode switch.
Background technology
Along with the fast development of integrated communications system, as the also corresponding increase of quantity of the antenna of information Vomitory, thereby increased the loss of cost and the feeder line of integrated information system.Beam direction can be cut (directional diagram reconstructable) and change antenna and can in real time change and transmit and receive the beam direction of antenna according to the variation of communication environment, thereby effectively avoids noise jamming, improves system gain and fail safe.In addition, the general use of beam direction switchable antenna one or seldom several feed port, can avoid the loss in signal building-up process.Below vehicle-mounted, airborne or antenna, have under the application scenarioss such as other radio circuits, the beam direction of antenna should avoid transmitting to the lower half-space, to reduce the interference for other microwave circuit.
Document " the wide angle scanning phase array of Wide-Angle Scanning Phased Array With Pattern Reconfigurable Elements(based on directional diagram reconstructable aerial) " [J] < < IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION > > VOL.59, NO.11, NOVEMBER2011:4071 – 4076Yan-Ying Bai, Shaoqiu Xiao, Ming-Chun Tang, et al, designed a kind of beam direction switchable antenna with three kinds of emission modes, this antenna comprises: rectangle dielectric substrate and printing metal floor thereunder, in the middle part of dielectric upper surface of base plate, print transmitting oscillator, in the both sides of oscillator, respectively print a parasitic metal patch, every parasitic metal patch forms by three sections, gap between every adjacent two sections connects a diode switch.When two diode switches on parasitic metal patch are all connected, three sections of this parasitism metal patch are linked to be an integral body, and its length is greater than transmitting oscillator, and the transmitting of antenna is played to reflex; When two diode switches on parasitic metal patch all disconnect, three sections of this parasitism metal patch can not be linked to be an integral body, and its length of every section is all less than transmitting oscillator, the transmitting of antenna is played to the effect of guiding into.For fear of antenna, to the lower half-space, launch, this antenna is printed metal floor at the lower surface of dielectric substrate, its length and width size is identical with dielectric substrate, but metal floor has played reflex to transmitting, make this antenna beam direction can not cover the region near place, floor plane.In order to make the wave beam of two kinds of endfire mode, more press close to floor, this antenna is thickeied 8mm by dielectric substrate, but because normally used dielectric substrate is generally no more than 2mm, thickening dielectric-slab must be made very difficult, and thickening dielectric-slab can not address this problem completely, this rectangular flat plate antenna, take that to grow place, limit direction be Y-axis, minor face place direction is X-axis, direction perpendicular to antenna panel is Z axis, set up coordinate system, this antenna can cover-71 °~78 ° in YOZ plane, can not cover full upper half-space.
Summary of the invention
The deficiency improvement that the present invention is directed to background technology has designed a kind of double mode beam direction switchable antenna, these antenna dielectric substrate both sides arrange respectively a Quasi-Yagi antenna that is connected with control circuit, by the break-make of PIN diode in control circuit, carry out the transmit direction of switched antenna wave beam, thereby reach can be in YOZ face cover antenna upper half-space the and lower half-space is not caused to interference, and the object reducing production costs.
Technical scheme of the present invention is to replace transmitting oscillator and the parasitic metal patch in background technology with Quasi-Yagi antenna, thereby increases antenna transmission angle, makes wave beam cover antenna upper half-space.The present invention adopts common dielectric substrate, this dielectric substrate interlude region lower surface arranges metal floor, upper surface center arranges distributing point, distributing point is connected respectively by two control circuits the Quasi-Yagi antenna of being located at dielectric substrate two side areas, two side areas lower surface arranges insulating material, and insulating material lower surface arranges metallic reflection plate.During work, by controlling the break-make of PIN diode, carry out the transmit direction of switched antenna wave beam.Thereby a kind of double mode beam direction switchable antenna of the present invention comprises: dielectric substrate with and the control circuit of upper surface, emitter, metal floor, insulating material, metallic reflection plate, coaxial feeder, key is that this dielectric substrate interlude region lower surface arranges metal floor, upper surface center arranges distributing point, distributing point is connected respectively by two control circuits the emitter of being located at dielectric substrate two side areas, this emitter adopts Quasi-Yagi antenna, two side areas lower surface arranges insulating material, insulating material lower surface arranges metallic reflection plate, coaxial feeder from below to antenna feed, outer conductor connection metal floor, inner wire connects the distributing point of dielectric upper surface of base plate through metal floor.
Described double mode beam direction switchable antenna, wherein control circuit sets gradually capacitance, PIN diode, wire by distributing point to Quasi-Yagi antenna; Capacitance is connected a grounded inductor in contact place altogether with PIN diode, and a branch road that connects successively inductance, resistance is set on wire in addition.
Described double mode beam direction switchable antenna, each Quasi-Yagi antenna is guided paster into by two metal patch oscillators and two metals and is formed, two metal patch oscillators are separately positioned on upper surface and the lower surface of dielectric substrate and are positioned at the both sides of wire, lower surface metal patch oscillator is connected with metal floor by wire, two metals are guided the equidistant upper surface that is evenly arranged on dielectric substrate of paster into, and are positioned at the outside of metal patch oscillator.
Described double mode beam direction switchable antenna, wherein insulating material is foamed material.
The present invention utilizes distributing point both sides to arrange respectively one and controls the Quasi-Yagi antenna of break-make by PIN diode, by controlling the transmit direction of the break-make switched antenna wave beam of PIN diode, thereby have can be in YOZ face cover antenna upper half-space the and lower half-space is not caused the characteristic of interference, the design adopts the material that is easy to processing and fabricating simultaneously, has reduced production cost.
Accompanying drawing explanation
Fig. 1 is the Facad structure schematic diagram of the background technology directional diagram reconstructable aerial with three kinds of emission modes;
Fig. 2 is the Facad structure schematic diagram of a kind of double mode beam direction switchable antenna of the present invention;
Fig. 3 is the side structure schematic diagram of a kind of double mode beam direction switchable antenna of the present invention;
Fig. 4 is the simulate and test return loss schematic diagram of antenna of the present invention;
Fig. 5 is that antenna of the present invention is at the 3D of 5.3GHz emulation directional diagram;
Wherein Fig. 5 (a) is antenna in pattern 3D emulation directional diagram for the moment, and Fig. 5 (b) is the 3D emulation directional diagram of antenna when pattern two.
Fig. 6 is that antenna of the present invention is at the 2D of 5.3GHz emulation directional diagram;
Wherein Fig. 6 (a) is antenna YOZ face directional diagram while being operated in pattern one and pattern two, and Fig. 6 (b) is antenna XOY face directional diagram while being operated in pattern one and pattern two.
Fig. 7 is the simulated gain of antenna of the present invention in working band.
In figure: 1. metal is guided paster into, 2. the metal patch oscillator of dielectric upper surface of base plate, 3. second segment sheet wire, 4. first paragraph sheet wire, 5. inductance, 6.PIN diode, 7. metal throuth hole 8. distributing points, 9. high impedance metal wire, 10. capacitance, 11. resistance, 12. dielectric substrates, the metal patch oscillator of 13. dielectric base lower surfaces, 14. metallic reflection plates, 15. metal floors, 16. coaxial feeders, 17. plastic foams.
Embodiment
Metal patch on metallic reflection plate 14, metal floor 15 and dielectric substrate 12 is the Copper Foil that thickness is 0.07mm, and metallic reflection plate 14 is of a size of 50*15.8mm
2, metal floor 15 is of a size of 50*59.2mm
2; Between dielectric substrate 12 and metallic reflection plate 14, fill and be of a size of 50*15.8*19.4mm
3, the relative dielectric constant plastic foam 17 that is 1.06; Dielectric substrate 12 is the polytetrafluoroethylene of relative dielectric constant 2.65, thickness 0.8mm, and it is of a size of 50*100mm
2; The characteristic impedance of coaxial feeder 16 is 50 Ω; Plated-through hole 7 diameters of dielectric substrate are 0.5mm.
The metal patch of dielectric substrate top as shown in Figure 2.The distributing point 8 of dielectric substrate 12 upper surfaces is of a size of 2*2mm
2; Metal weld tabs between capacitance and PIN diode is 3*3mm
2, the metal weld tabs of other tie points is 2*2mm
2; Capacitance 10 is 10pF, and the length of high impedance line 9 is about 1/4 λ (the work centre frequency that λ is antenna), and it is of a size of 11.5*0.4mm
2; Inductance 5 is 1mH, and the spacing at inductance place is 2mm; First paragraph sheet wire 4 is of a size of 20*3.1mm
2; Second segment sheet wire 3 is of a size of 9.7*1.4mm
2; The resistance of resistance 11 is 2.2k Ω; The metal patch oscillator 2 that is positioned at dielectric upper surface of base plate is of a size of 11*1.8mm with the metal patch oscillator 13 that is positioned at dielectric base lower surface
2; The size that metal is guided paster 1 into is 14*2mm
2; Two metals are guided between paster and metal patch oscillator interval 2mm between two into.
The negative pole in the DC control signal source of 5V is connected on metal floor, positive pole is connected on one end of resistance 11, utilize DC control signal source to control the break-make of PIN diode, when the right PIN diode conducting and the cut-off of left side PIN diode, right-hand member antenna transmission body running is now pattern one (mode1); When the right PIN diode cut-off and during the PIN diode conducting of the left side, the antenna transmission body running of left end, is now pattern two (mode2).Because antenna structure is symmetrical, the return loss under two kinds of mode of operations is identical with gain, and simulation result respectively as shown in Figure 3 and Figure 6; The emulation directional diagram of two kinds of mode of operations as shown in Figure 4 and Figure 5.Simulation result shows, the working frequency range of antenna is 5.00GHz-5.65GHz, the YOZ face main lobe of two kinds of patterns points to respectively θ=± 55 °, 3dB lobe width is 110 °, main lobe in XOY face points to and is respectively φ=± 90 °, 3dB lobe width is 120 °, and in working frequency range, gain is 7.3dBi-7.7dBi.The simulation result of this embodiment can reach the object that covers upper half-space and the lower half-space is not produced transmitting in YOZ plane, and in working frequency range, gain is mild.The in the situation that of other real needs, can and regulate transmitting pattern with the distance of dielectric substrate by the size of accommodation reflex plate, expanded the range of application of this antenna.