Summary of the invention
Technical problem to be solved by this invention is, for the defect that existing microwave antenna processing is difficult for, cost is high, to provide a kind of super material microwave antenna simple, low cost of manufacture of processing.
The technical solution adopted for the present invention to solve the technical problems is:
A super material microwave antenna, comprises super material panel, feed, first order subreflector and second level subreflector, and the center of described super material panel is provided with the first centre bore, and the center of described second level subreflector is provided with the second centre bore; Described first order subreflector is embedded on the first centre bore of described super material panel, and described feed is embedded on the second centre bore of described second level subreflector;
Described first order subreflector is the hyperboloid of revolution, and described second level subreflector is ellipse of revolution face;
Described super material panel comprises core layer, and described core layer comprises at least one core layer lamella, and described core layer lamella comprises the base material of sheet and is arranged on a plurality of artificial micro-structural on base material;
Described core layer lamella according to refraction index profile can be divided into be distributed in described the first centre bore around and with a plurality of annular regions of the concyclic heart of described the first centre bore, in described annular region, the refractive index at same radius place is identical, and the increase refractive index along with radius in annular region region separately reduces gradually, the minimum value of the refractive index of the annular region in inner side in adjacent two annular regions is less than the maximum of the refractive index of the annular region in outside.
Further, described first order subreflector and the confocal axle of second level subreflector.
Further, described first order subreflector and the focal axis of second level subreflector and the symmetry axis of described super material panel overlap.
Further, the phase center of described feed is placed in the outside focus of described first order subreflector, and the far-end focus of described second level subreflector is placed in the inner side focus of first order subreflector.
Further, described core layer comprises the core layer lamella that a plurality of refraction index profile are identical and be parallel to each other.
Further, described first order subreflector and second level subreflector are metal mirror.
Further, each annular region in described core layer lamella all has identical variations in refractive index scope.
Further, described super material panel also comprises the matching layer that is arranged on core layer both sides, to realize the impedance matching from air to core layer.
Further, a plurality of artificial micro-structural shape of each core layer lamella of described core layer is identical, in described annular region, a plurality of artificial micro-structural at same radius place has identical physical dimension, and the physical dimension along with the artificial micro-structural of increase of radius in annular region region separately reduces gradually, adjacent two annular regions, in the annular region in inner side, the physical dimension of the artificial micro-structural of physical dimension minimum is less than the physical dimension of the artificial micro-structural of physical dimension maximum in the annular region in outside.
Further, described artificial micro-structural is the alabastrine metal micro structure of plane.
The beneficial effect of the super material microwave antenna of the present invention: the present invention utilize super material can converge electromagnetic character and utilize the hyperboloid of revolution and ellipse of revolution face as first order subreflector and second level subreflector, can make the structure of antenna compacter, and in effect, be equivalent to the microwave antenna with long-focus, regulate the Energy distribution on bore face simultaneously, thereby improve the aperture efficiency of antenna, obtained good far-field radiation field response; In addition, its difficulty of processing is little, and cost is low.
Embodiment
As shown in Figure 1, according to super material microwave antenna of the present invention, comprise feed 10, first order subreflector 20, second level subreflector 30 and super material panel 40.Described super material panel 40 is provided with the first circular centre bore that is positioned at its center, described second level subreflector 30 is provided with the second centre bore that is positioned at its center, described super material panel 40 comprises core layer 401 and is arranged on the matching layer 402 of core layer 401 both side surface, described core layer 401 comprises at least one core layer lamella, described core layer lamella comprises the base material of sheet and is arranged on a plurality of artificial micro-structural on base material, described core layer lamella according to refraction index profile can be divided into be distributed in the first centre bore around and with a plurality of annular regions of the concyclic heart of described the first centre bore.In adjacent two annular regions, the minimum value of the refractive index of the annular region in inner side is less than the maximum of the refractive index of the annular region in outside.It is in order better to describe the present invention that core layer lamella is divided into a plurality of annular regions according to refractive index, and does not mean that core layer lamella of the present invention has this kind of practical structures.
In the present invention, the longitudinal cross-section of described super material panel 40 can be the rectangle with center hole, also can be annular, it can also be the figure that other those skilled in the art can expect, as shown in Figure 2, described super material panel 40 is annular, the annular matching layer that the super material panel of this annular comprises toroid core layer and is positioned at these toroid core layer both sides, and matching layer is used for electromagnetic wave and is transferred to from air the impedance matching that toroid core layer or toroid core layer are transferred to air.Wherein, toroid core layer comprises that at least one toroid core synusia layer forms.Each toroid core synusia layer can be divided into a plurality of annular regions according to the refractive index rule of arranging, for example, as shown in Figure 2, this toroid core synusia layer is divided into H1, H2, tri-regions of H3 according to the rule of arranging of refractive index, wherein in H1, H2, H3 region separately, the increase refractive index along with radius reduces gradually, and the refractive index of same radius is identical; In H1, H2, tri-regions of H3, all there is identical variations in refractive index scope, for example, the minimum value of the refractive index of the annular region in inner side is less than the maximum of the refractive index of the annular region in outside: the refractive index in three regions is 5,4,3,2,1, and in adjacent two annular regions.At the intersection in H1 and H2 region, the refractive index that is positioned at the region of H1 is 1, and the refractive index that is still positioned at H2 region is that the intersection between 5, H2 and H3 region is also like this exactly.
In the present invention, described first order subreflector 20 is arranged on the first centre bore of super material panel 40, and is positioned on the axis of described super material panel 40, and feed 10 overlaps with the axis of super material panel 40 with the line at the center of core layer lamella.As shown in Figure 1, feed 10 is embedded on second centre bore at subreflector 30 center, the second level; First order subreflector 20 is embedded in the inner circle of the super material panel 40 of annular; The phase center of feed 10 (needing to measure) is placed on the outside focus A of first order subreflector 20, and the far-end focus of second level subreflector 30 is placed on the inner side focus B of first order subreflector 20, and the near-end focus of second level subreflector 30 is designated as C;
Described first order subreflector 20 is the hyperboloid of revolution, second level subreflector 30 is ellipse of revolution face, the hyperboloid of revolution in this enforcement and ellipse of revolution face are respectively metal rotation hyperboloid and metal rotation ellipsoid, the preferably copper hyperboloid of revolution and copper ellipse of revolution face.The above-mentioned hyperboloid of revolution and the confocal axle of ellipse of revolution face, and the two focal axis overlaps with the symmetry axis of super material panel 40; Described feed 10 all has stent support with super material panel 40, and in figure and not shown support, it is not core of the present invention, adopts traditional supporting way.Feed 10 is preferably horn antenna in addition.
Described core layer 401 comprises the core layer lamella that a plurality of refraction index profile are identical and be parallel to each other.A plurality of core layer lamellas fit tightly, each other can be bonding by double faced adhesive tape, or be fixedly connected with by bolt etc.
Artificial micro-structural of the present invention is preferably metal micro structure, and described metal micro structure is comprised of one or more metal wire.Metal wire itself has certain width and thickness.Metal micro structure of the present invention is preferably the metal micro structure with isotropic electromagnetic parameter, and described metal micro structure is the alabastrine metal micro structure of plane.
For the artificial micro-structural with planar structure, isotropism, refer to on this two dimensional surface with arbitrary electromagnetic wave of unspecified angle incident, electric field response and the magnetic responsiveness of above-mentioned artificial micro-structural in this plane is all identical, is also that dielectric constant is identical with magnetic permeability; For the artificial micro-structural with three-dimensional structure, isotropism refers to the electromagnetic wave for incident in three-dimensional either direction, and electric field response and the magnetic responsiveness of each above-mentioned artificial micro-structural on three dimensions is all identical.When artificial micro-structural is 90 degree rotational symmetry structure, artificial micro-structural has isotropic feature.
For two-dimension plane structure, 90 degree Rotational Symmetries refer to that it overlaps with original structure after any 90-degree rotation of rotating shaft perpendicular to this plane and its symmetrical centre of mistake around one in this plane; For three-dimensional structure, if there are 3 rotating shafts of vertical and common intersection point (intersection point is pivot) between two, this structure is all overlapped after arbitrary rotating shaft 90-degree rotation or symmetrical with an interface with original structure with original structure, this structure is 90 degree rotational symmetry structures.
Known refractive index
wherein μ is relative permeability, and ε is relative dielectric constant, and μ and ε are collectively referred to as electromagnetic parameter.Experiment showed, when electromagnetic wave passes through refractive index dielectric material heterogeneous, can be to the large direction deviation of refractive index (to the large super material cell deviation of refractive index).Therefore, core layer of the present invention has to electromagnetic wave the effect of converging, the electromagnetic wave that send satellite or base station etc. is first by
feed 10 emitting electromagnetic waves, successively after
secondary reflection 30 reflections of
first order subreflector 20 and the second level, again by the effect of converging of
super material panel 40, therefore, the refraction index profile of appropriate
design core layer 401, can so that the electromagnetic wave that send satellite or base station etc. successively through first reflection, for the second time reflection after, through super material panel, converge again, can be by electromagenetic wave radiation in free space, and the gain that can improve antenna.If in the situation that the material of base material is selected, can be by the shape of the artificial micro-structural of design, the electromagnetic parameter that physical dimension and/or artificial micro-structural arranging on base material obtains super material internal distributes, in the present invention, a plurality of artificial micro-structural shape of each core layer lamella of described
core layer 401 is identical, in described annular region, a plurality of artificial micro-structural at same radius place has identical physical dimension, and the physical dimension along with the artificial micro-structural of increase of radius in annular region region separately reduces gradually, adjacent two annular regions, in annular region in inner side, the physical dimension of the artificial micro-structural of physical dimension minimum is less than the physical dimension of the artificial micro-structural of physical dimension maximum in the annular region in outside, thereby design the refraction index profile of each core layer lamella.First from the needed effect of super material, calculate the electromagnetic parameter spatial distribution of excess of export material internal, according to the spatial distribution of electromagnetic parameter, select the shape of artificial micro-structural, physical dimension (having deposited in advance multiple artificial micro-structural data in computer), to the design of artificial micro-structural, can use the method for exhaustion, for example first select an artificial micro-structural with given shape, calculate electromagnetic parameter, the contrast that the result obtaining and we are wanted, circulation repeatedly, till the electromagnetic parameter that finds us to want, if found, the design parameter that has completed artificial micro-structural is selected, if do not find, change a kind of artificial micro-structural of shape, repeat circulation above, till the electromagnetic parameter that finds us to want.If still do not found, said process can not stop yet.The artificial micro-structural that is to say the electromagnetic parameter that has only found our needs, program just can stop.Because this process is all completed by computer, therefore, seem complicated, in fact can complete soon.
In the present invention, the base material of described core layer 401 is made by ceramic material, macromolecular material, ferroelectric material, ferrite material or ferromagnetic material etc.Macromolecular material is available polytetrafluoroethylene, epoxy resin, F4B composite material, FR-4 composite material etc.For example, the electrical insulating property of polytetrafluoroethylene is very good, therefore can electromagnetic electric field not produced and be disturbed, and have good chemical stability, corrosion resistance, long service life.
In the present invention, described metal micro structure is the metal wires such as copper cash or silver-colored line.Above-mentioned metal wire can be attached on base material by etching, plating, brill quarter, photoetching, electronics is carved or ion is carved method.Certainly, also can adopt three-dimensional laser processing technology.
As shown in Figure 1, be the structural representation of the super material panel of first embodiment of the invention, in the present embodiment, described super material panel also comprises the
matching layer 402 that is arranged on core layer both sides, to realize from air to
core layer 401 impedance matching.We know, the refractive index between medium differs larger, when electromagnetic wave incides another medium from a medium, reflect greatlyr, and reflection is large, means the loss of energy, at this time just needs the coupling of refractive index, known refractive index
wherein μ is relative permeability, and ε is relative dielectric constant, and μ and ε are collectively referred to as electromagnetic parameter.We know that the refractive index of air is 1, therefore, design like this matching layer, and refractive index and the air of a side of close air are basic identical, and the core layer lamella refractive index that the refractive index of a side of close core layer is joined with it is basic identical.Like this, just realized the index matching from air to core layer, reduced reflection, energy loss can reduce greatly, and what electromagnetic wave can transmit like this is farther.
In sum, the present invention utilizes super material can converge electromagnetic character and utilize the hyperboloid of revolution as subreflector, can make the structure of antenna compacter, and in effect, be equivalent to the microwave antenna with long-focus, regulate the Energy distribution on bore face simultaneously, thereby improve the aperture efficiency of antenna, obtained good far-field radiation field response; In addition, its difficulty of processing is little, and cost is low.
By reference to the accompanying drawings embodiments of the invention are described above; but the present invention is not limited to above-mentioned embodiment; above-mentioned embodiment is only schematic; rather than restrictive; those of ordinary skill in the art is under enlightenment of the present invention; not departing from the scope situation that aim of the present invention and claim protect, also can make a lot of forms, within these all belong to protection of the present invention.