Artificial magnetic conductor system and method for manufacturing

Information

  • Patent Grant
  • 6411261
  • Patent Number
    6,411,261
  • Date Filed
    Friday, April 27, 2001
    23 years ago
  • Date Issued
    Tuesday, June 25, 2002
    22 years ago
Abstract
The invention provides an artificial magnetic conductor (AMC) system and method for manufacturing. The AMC has a post plane with posts and slots. The posts are operatively disposed adjacent to conductive shapes on one or more frequency selective surfaces. The posts formably extend from the post plane.
Description




FIELD OF THE INVENTION




This invention generally relates to frequency selective surfaces. More particularly, this invention relates to systems and methods for manufacturing artificial magnetic conductors.




BACKGROUND OF THE INVENTION




An artificial magnetic conductor (AMC) generally is an engineered material having a planar, electrically thin, anisotropic structure that is a high-impedance surface for electromagnetic waves. The electrically thin structure has a typical height in the range of about λ/100 through about λ/50, where λ is a free space wavelength. At microwave frequencies in the range of about 300 MHz through about 3 GHz, the structure also is physically thin. A typical AMC structure is two-layered, periodic, and magnetodielectric, and is engineered to have a specific tensor permittivity and permeability behavior with frequency in each layer. The AMC properties may be limited over a frequency band or bands. Near the resonant frequency of the structure, the reflection amplitude is near unity and the reflection phase at the surface is near zero degrees. When operating as a high impedance surface, an AMC suppresses transverse electric (TE) and transverse magnetic (TM) mode surface waves over one or more frequency bands.




The high impedance surface may be used in antenna and similar applications. The antenna applications include “paste-on” antennas, internal and wireless handset antennas, global positioning satellite (GPS) antennas, and the like. Other applications include suppressing surface waves, mitigating multi-path signals near the horizon, reducing the absorption of radiated power, directing the radiation pattern, and lowering the aperture size and weight.





FIG. 14

is an AMC according to the prior art. The AMC may be made using printed circuit board manufacturing and other methods know in the art to form a “bed of nails” structure—a frequency selective surface (FSS) connected by vias to a backplane. A spacer or dielectric layer is disposed adjacent to the backplane. The spacer layer may be any material suitable for a printed circuit board substrate such as a fiber reinforced polymer, a copper laminate epoxy glass (FR4), and the like. The backplane is made from a metal such as copper. The vias are plated-through holes formed in the spacer layer and are made of a metal such as copper. The vias may be hollow or solid and are connected to the backplane. The FSS has conductive shapes printed on a substrate. The conductive shapes are made of a metal such as copper and are conductively attached to the vias. The substrate typically is much thinner than the spacer layer and may be any material suitable for a printed circuit board substrate such as polyimide.




The vias, multi-layer construction, and dissimilar layers and substrates increase manufacturing costs. The type of dielectric material also may increase the cost of AMC antennas. The dielectric material typically used as the spacer layer is relatively heavy and represents as much as 98 percent of the weight of a finished AMC. This dielectric material also may contribute significantly to the cost of thicker AMC designs. This dielectric material makes the spacer layer more rigid, so that the resulting AMC is rigid and planar. A rigid AMC may not be suitable for some applications such as those requiring a conformable (non-planar) or flexible AMC.




SUMMARY




This invention provides an artificial magnetic conductor (AMC) system and manufacturing method. The AMC has one or more posts or post assemblies formably extending from a post plane adjacent to one or more frequency selective surfaces.




The AMC may comprise a post plane and one or more frequency selective surfaces in one embodiment. The post plane has one or more posts and one or more slots. The one or more posts formably extend from the post plane. The frequency selective surfaces have one or more conductive shapes. The posts are operatively disposed adjacent to the conductive shapes.




The AMC also may comprise one or more frequency selective surfaces and a post plane in another embodiment. The post plane has one or more post assemblies and one or more slots. The one or more post assemblies formably extend from the post plane. Each post assembly has one or more posts and one or more plates. The one or more plates are operatively disposed adjacent to the one or more frequency selective surfaces.




In a method for manufacturing an AMC, one or more posts and one or more slots are formed in a post plane. The one or more posts formably extend from the post plane. The one or more posts are operatively disposed adjacent to one or more frequency selective surfaces.




In another method for manufacturing an AMC, one or more post assemblies and one or more slots are formed in a post plane. Each post assembly has one or more posts and one or more plates. The one or more posts formably extend from the post plane. The one or more plates are operatively disposed adjacent to one or more frequency selective surfaces.




Other systems, methods, features, and advantages of the invention will be or will become apparent to one skilled in the art upon examination of the following figures and detailed description. All such additional systems, methods, features, and advantages are intended to be included within this description, within the scope of the invention, and protected by the accompanying claims.











BRIEF DESCRIPTION OF THE FIGURES




The invention may be better understood with reference to the following figures and detailed description. The components in the figures are not necessarily to scale, emphasis being placed upon illustrating the principles of the invention. Moreover, like reference numerals in the figures designate corresponding parts throughout the different views.





FIG. 1

represents perspective view of an unassembled artificial magnetic conductor (AMC) according to a first embodiment.





FIGS. 2A and 2B

represent assembled views of the AMC in

FIG. 1

, where:

FIG. 2A

represents a top view of the AMC; and

FIG. 2B

represents a side view of the AMC.





FIGS. 3A

,


3


B, and


3


C represent side views of a conductive shape operatively disposed adjacent to a post in an AMC according to alternative embodiments; where

FIG. 3A

is a side view of an AMC having a conductive shape operatively attached to a post according to one aspect;

FIG. 3B

is a side view of an AMC having a conductive shape operatively attached to a post according to another aspect; and where

FIG. 3C

is a side view of an AMC having a space between a conductive shape and a post according to another aspect.





FIGS. 4A and 4B

represent side views of an AMC according to a second embodiment; where

FIG. 4A

represents a side view of the AMC having a space between the frequency selective surface and the posts; and where

FIG. 4B

represents a side view the AMC with no space between the frequency selective surface and the posts.





FIG. 5

represents a perspective view of an unassembled AMC according to a third embodiment.





FIG. 6

represents a perspective view of an unassembled AMC according to a fourth embodiment.





FIG. 7

represents a side view of a post formed by a portion of a post plane for an AMC according to the fourth embodiment.





FIG. 8

represents a perspective view of a post plane for an AMC according to a fifth embodiment.





FIG. 9

represents a side view of a shoulder tab or post formed by a portion of a post plane for an AMC according to the fifth embodiment.





FIG. 10

represents a perspective view of an unassembled AMC according to a sixth embodiment.





FIGS. 11A and 11B

represent one embodiment of a post assembly in a post plane for an AMC; where

FIG. 11A

represents a top view of the post assembly as initially formed in the post plane; and

FIG. 11B

represents a perspective view of the post assembly as configured to position a plate adjacent or connected to a frequency selective surface.





FIGS. 12A and 12B

represent another embodiment of a post assembly in a post plane for an AMC; where

FIG. 12A

represents a top view of the post assembly as initially formed in the post plane; and

FIG. 12B

represents a perspective view of the post assembly as configured to position a plate adjacent or connected to a frequency selective surface.





FIG. 13

represents a flowchart of a method for manufacturing an AMC.





FIG. 14

is an AMC according to the prior art.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS





FIGS. 1-2

represent an artificial magnetic conductor (AMC)


100


according to a first embodiment.

FIG. 1

represents a perspective view of an unassembled AMC


100


.

FIG. 2A

represents a top view of the AMC


100


as assembled.

FIG. 2A

represents a side view of the AMC


100


as assembled. The AMC


100


may be an antenna or similar device and may be part of or connected to an electronic device (not shown) such as a wireless communication device (cellular telephone, radio, etc.), a GPS device, and the like. While components are shown in a particular configuration, other or additional components and different configurations may be used.




The AMC


100


comprises a frequency selective surface (FSS)


102


operatively disposed adjacent to one or more tabs or posts


106


, which formably extend from a post plane


104


. In one aspect, the FSS


102


may be connected to the posts


106


when assembled. In another aspect, there may be a space between the FSS


102


and the posts


106


as discussed below. The FSS


102


includes one or more conductive shapes


110


printed or plated onto a substrate


112


. The conductive shapes


110


may be in one or more layers. The substrate


112


may be thinner than the height, h, of the posts


106


and may be any material suitable for a printed circuit board substrate such as polyimide. The conductive shapes


110


may be any shapes or combination of shapes suitable for operation of the AMC


100


, including rectangles, hexagons, or loops. The conductive shapes


110


are arranged periodically on the substrate


112


and separated by a gap, g. In one aspect, the conductive shapes


110


have a square configuration with a side, b. The conductive shapes


110


may be made of one or more electrically conductive materials and may be conductively attached to the posts


106


. Conductively attached includes physical and non-physical connections between the posts


106


and the conductive shapes


110


suitable for operation of the AMC


100


. Electrically conductive materials include metals such as copper in elemental or near elemental form, alloys, composites, and other materials having suitable electrical properties for operation of the AMC


100


.




The posts


106


formably extend from the post plane


104


. A portion of the post plane


104


forms each post


106


, leaving a slot or voided area


108


in post plane


104


. The slots


108


essentially reduce the surface area of the post plane


104


, which may reduce the weight of the AMC


100


. The post plane


104


may be made from one or more materials having suitable electrical conductive and plastic deformation properties. In one aspect, the post plane


104


comprises copper or a copper alloy. In another aspect, the post plane


104


comprises aluminum or an aluminum alloy.




Stamping, vacuum forming, chemical milling, casting, die-casting, other processes, or a combination of such processes may form the tabs or posts


106


in the post plane


104


. In one aspect, a sheet of metal or the post plane


104


is stamped, chemically milled, or otherwise machined to create tabs or the posts


106


, which are connected to the sheet at one end. Each post


106


is cut and bent out of the plane of the sheet, leaving a slot


108


in the sheet or post plane


104


and creating a post


106


formably extending toward the FSS


102


. All or some of the posts


106


may be essentially parallel to each other. The posts


106


may be at about a right angle or other selected angle to the post plane


104


. The posts


106


may be slanted at an angle within the range of about 60 through about 90 degrees relative to the post plane


104


. The posts


106


may be slanted at a common angle. The tabs or posts


106


may be formed at the same time or sequentially. In one aspect, the height of the tabs above the post plane is in the range of about 0.060 inches through about 0.250 inches. In another aspect, the height of the tabs above the post plane is in the range of about 0.005λ through about 0.05λ, where λ is the wavelength. The period and lattice arrangement of the posts


106


may match the periodic features of the FSS


102


. The period may be as small as about 0.2 inches for a square lattice. In one aspect, the period may be as small as about 0.2 inches for a square lattice. In another aspect, the period may be as small as about 0.02λ for a square lattice. In a further aspect, the period of the posts may be much smaller than the period of the FSS such that one unit cell of the AMC contains multiple posts.




The posts


106


are operatively disposed adjacent and may be attached to the FSS


102


. Operatively disposed includes non-conductive attachment and conductive attachment. Non-conductive attachment may be done using an adhesive. Conductive attachment may be done by soldering or conductive adhesive.





FIGS. 3A

,


3


B, and


3


C are side views of a conductive shape


310


operatively disposed adjacent to a post


306


in an AMC according to alternative embodiments. Other arrangements may be used where the conductive shape


310


is operatively disposed adjacent to the post


306


. In

FIG. 3A

, the post


306


formably extends from a post plane


304


. The post


306


has a pin


322


extending from a shoulder


324


. The pin


322


protrudes partially or completely through an aperture


326


formed in the conductive shape


310


. The shoulder


324


may establish the spacing between the post plane


304


and the conductive shape


310


. The post


306


and the pin


322


may not have a physical connection with the conductive shape


310


. An adhesive, solder, or other material (not shown) may be disposed in the aperture


326


, essentially surrounding the pin


322


. In

FIG. 3B

, the post


306


formably extends from a post plane


304


. The post


306


may have a physical connection with the conductive shape


310


by soldering, adhesive, and the like. In

FIG. 3C

, the post


306


formably extends from a post plane


304


. The post


306


has a pin


322


extending from a shoulder


324


. Alternatively, the post


306


may not have a pin extending from a shoulder. The conductive shape


310


is disposed in a space S from the post


306


. In one aspect, the space S comprises the volume between the conductive shape


310


and the shoulder


324


. The space S may comprise other volumes such as the volume between the pin


322


and the conductive shape


310


. The period of the posts


306


in the AMC may be selected to reduce or eliminate the electrical or conductive contact between the post


306


and the conductive shape


310


. In one aspect, if the period of the posts in the AMC is less than the height h of the posts (see FIG.


1


), then the posts


306


do not have to be in electrical or conductive contact with the conductive shape


310


. In another aspect, if the period of the posts in the AMC is less than or equal to about one-half of the height h of the posts, then the posts


306


do not have to be in electrical or conductive contact with the conductive shape


310


.





FIGS. 4A and 4B

represent side views of an artificial magnetic conductor (AMC)


400


according to a second embodiment. The AMC has a curvilinear configuration. Curvilinear includes any non-linear configuration including an arcs and combinations of non-linear configurations. A curvilinear configuration may include any non-planar configuration and may have different curved, arc, and planar shapes along different axes. The AMC comprises a frequency selective surface (FSS)


402


operatively disposed adjacent to one or more posts


406


, which formably extend from a post plane


404


. In one aspect, the FSS


402


may be connected to the posts


406


when assembled. In another aspect, there may be a space between the FSS


402


and the posts


406


as previously discussed.

FIG. 4A

represents a side view of the AMC


400


having a space between the FSS


402


and the posts


406


.

FIG. 4B

represents a side view of the AMC


400


with no space S between the FSS


402


and the posts


406


. A portion of the post plane


404


forms each post


406


, which formably extend from the post plane


404


. As discussed below, a dielectric layer (not shown) may be disposed between the FSS


402


and the post plane


404


and a backing film


416


(not shown) may be disposed adjacent to the post plane.

FIG. 5

represents a perspective view of an unassembled artificial magnetic conductor (AMC)


500


according to a third embodiment. The AMC


500


comprises a frequency selective surface (FSS)


502


operatively disposed adjacent to one or more posts


506


, which formably extend from a post plane


504


. In one aspect, the FSS


502


may be connected to the posts


506


when assembled. In another aspect, there may be a space between the FSS


502


and the posts


506


as previously discussed. A portion of the post plane


504


forms each post


506


, leaving a slot or voided area


508


in the post plane


504


. The posts


506


formably extend from the post plane


504


and operatively connect to the FSS


502


in one aspect. A dielectric layer


514


is disposed between the FSS


502


and the post plane


504


. A backing film


516


is disposed adjacent to the post plane. While components are shown in a particular configuration, other or additional components and different configurations may be used.




The dielectric layer


514


is disposed between the FSS


502


and the post plane


504


. The dielectric layer


514


may be any material suitable for a printed circuit board substrate such as a fiber reinforced polymer, a copper laminate epoxy glass (FR4), and the like. The dielectric layer


514


may be air or another suitable gas or liquid or solid material. The posts


506


extend through the dielectric layer


514


. In one aspect, holes or suitable openings are drilled or punched in the dielectric layer


514


to receive the posts


506


. In another aspect, the dielectric layer


514


is cast in a liquid form around the posts


506


. The liquid form subsequently dries or cures into a solid.




The backing film


516


is conductive and may electrically short the slots


508


in the post plane


504


. Without the backing film, the slots


508


may provide anisotropic impedance to the flow of electric currents on the post plane


504


. The anisotropic impedance may be a problem for some applications. The backing film


516


may be made from one or more electrically conductive materials such as copper or aluminum tape.





FIG. 6

represents a perspective view of an unassembled artificial magnetic conductor (AMC)


600


according to a fourth embodiment. The AMC


600


comprises a frequency selective surface (FSS)


602


operatively disposed adjacent to one or more tabs or posts


106


, which formably extend from a post plane


104


. In one aspect, the FSS


602


may be connected to the posts


106


when assembled. In another aspect, there may be a space between the FSS


602


and the posts


606


as previously discussed. A portion of the post plane


604


forms each post


606


. The posts


606


formably extend from the post plane


604


and operatively connect to the FSS


602


in one aspect. While posts are shown in a square lattice configuration, other lattice configurations may be used, such as triangular or hexagonal.





FIG. 7

shows a side view of a projection or post


606


formed by a portion of the post plane


604


for the AMC


600


. In one aspect, a sheet of metal or the post plane


604


is drawn, pressed, vacuum formed, or otherwise deformed to create an inverted, cone-shaped post


606


. The post


606


may have an essentially flat top surface to operatively attach to the FSS. The post


606


also may form a shoulder (not shown) and a pin (not shown) to operatively attach to the FSS. The post


606


creates a slot or voided area


608


in the post plane


604


, where the slot


608


is essentially covered or surrounded by the post


606


. This configuration may reduce or eliminate the potential leakage of electromagnetic energy through the post plane


604


without the use of a backing film.





FIGS. 8 and 9

represent an artificial magnetic conductor (AMC)


800


according to a fifth embodiment.

FIG. 8

is a perspective view of a post plane


804


for the AMC


800


.

FIG. 9

is a side view of a shoulder tab or post


806


formed by a portion of the post plane


804


for the AMC


800


. The AMC


800


comprises a first frequency selective surface (FSS) layer


818


and a second frequency selective surface (FSS) layer


820


connected by one or more posts


806


to a post plane


804


. A portion of the post plane


804


forms each post


806


. The posts


806


formably extend from the post plane


804


and operatively connect to the first and second FSS layers


818


and


820


. In one aspect, a sheet of metal or the post plane


804


is mechanically stamped to form the shoulder tabs or posts


806


. The shoulder tabs


806


may have two shoulders of different sizes to support the first and second FSS layers


818


and


820


. This embodiment may be used to provide a dual-band AMC. While components are shown in a particular configuration, other or additional components of a different configuration may be used such as an extrusion similar to FIG.


7


.





FIG. 10

represents a perspective view of an unassembled artificial magnetic conductor (AMC)


1000


according to a sixth embodiment. The AMC


1000


comprises a frequency selective surface (FSS)


1002


operatively disposed adjacent to a post plane


1004


. Operatively disposed includes capacitive coupling, conductively attached, and other arrangements suitable for operation of the AMC


1000


. Conductively attached includes physical and non-physical connections. The AMC


1000


may have a dielectric layer (not shown) disposed between the FSS


1002


and the post plane


1004


. The AMC


1000


also may have a backing film (not shown). The FSS


1002


and post plane


1004


may have flat, curvilinear, or other configurations. The post assemblies


1036


formably extend from the post plane


1002


. Each post assembly


1036


comprises a post


1006


and a plate


1034


, which may be formed to be parallel to the FSS


1002


. The plate


1034


may be capacitively coupled to the FSS through an air or dielectric layer. While components are shown in a particular configuration, other or additional components and different configurations may be used. The FSS


1002


has one or more conductive shapes


1010


arranged on a substrate


1012


. In one aspect, the conductive shapes


1010


have rectangular configurations and are arranged in a periodic formation. The conductive shapes


1010


may have a hexagonal, loop, or other configurations and may be arranged in another periodic or suitable formation. The conductive shapes


1010


may be arranged in one or more layers, forming a single or double-sided FSS or another configuration. If the conductive shapes


1010


are arranged in layers, the conductive shapes in one layer maybe offset to the conductive shapes in another layer. The substrate


1012


may be a dielectric or other suitable material.




The post plane


1004


has one or more post assemblies


1036


. A portion of the post plane


1004


forms each post assembly


1036


, leaving a slot or voided area


1008


in the post plane


1004


. The post assemblies


1036


may be arranged in a periodic or other suitable configuration and may be arranged to increase the number of post assemblies


1036


obtained from the post plane


1004


. The post assemblies


1036


may have the same or different configurations and may have the same or variable orientations. The post assemblies


1036


may have an alternating orientations, where adjacent post assemblies


1036


are arranged in different or opposite directions.




The post


1006


and the plate


1034


are configured along one or more hinge or bend portions


1030


to form the post assembly


1036


. When assembled, the plate


1034


may be operatively disposed adjacent or may be connected to the FSS


1002


. The post assembly


1034


may provide a RF connection between the posts


1006


and the FSS


1002


, without using solder or other connection techniques. Each post assembly


1036


may have multiple posts (not shown) and multiple plates (not shown). The post


1006


and plate


1034


may have essentially straight and flat shapes and may have other shapes including curvilinear and other configurations. The post


1006


and plate


1034


may form a single curvilinear shape having one hinge or bend portion


1030


for connection to the post plane


1004


. Some or all of the posts


1006


may be essentially parallel to each other and slanted at a common angle relative to the post plane


1004


. The posts


1006


may be at a right angle or other selected angle relative to the post plane


1004


. The posts


1006


may form an angle in the range of about 60 through about 90 degrees relative to the post plane


1004


. The plates


1034


are essentially parallel to at least one of the FSS


1002


and the post plane


1004


. The plates


1034


may have flat, curvilinear, or other suitable configurations, which may be the same as the FSS


1002


and the post plane


1004


.




The plates


1034


may be operatively disposed adjacent to the conductive shapes


1010


in the FSS


1002


. In one aspect, the plates


1034


are disposed to form a space between the plates


1034


and the FSS


1002


. A dielectric film (not shown) may form or essentially fill the space. The dielectric film may be part or an extension of the dielectric layer between the FSS and the post plane as previously discussed. In another aspect, the plates


1034


are connected to one or more of the conductive shapes


1010


in one or more layers of the FSS


1002


. The plates


1034


may be connected to the conductive shapes using an adhesive, solder, or another suitable connection medium. In a further aspect, the plates


1034


form one or more of the conductive shapes


1010


in a single layer or single-sided FSS. In yet another aspect, the plates


1034


form one or more of the conductive shapes


1010


in a multiple layer FSS. The plates


1034


may form part or all of the bottom layer of conductive shapes


1010


in a double layer or double-sided FSS.





FIGS. 11A and 11B

represent one embodiment of a post assembly


1136


in a post plane


1104


for an artificial magnetic conductor (AMC). The post assembly


1136


comprises a post


1106


and a plate


1134


configured at hinge or bend portions


1130


. The post assembly


1136


forms a slot


1108


in the post plane


1104


.

FIG. 11A

represents a top view of the post assembly


1136


as initially formed in the post plane


1104


.

FIG. 11B

represents a perspective view of the post assembly


1136


as configured in one aspect to position the plate


1134


adjacent or connected to a frequency selective surface.





FIGS. 12A and 12B

represent another embodiment of a post assembly


1236


in a post plane


1204


for an artificial magnetic conductor (AMC). The post assembly


1236


forms a slot


1208


in the post plane


1204


and comprises a post


1206


and a plate


1234


configured at hinge or bend portions


1230


. The plate


1234


has open sections


1232


, which form the plate


1234


into a “rectangular-cloverleaf” configuration. Other configurations may be used including those with more or less open sections and those forming curvilinear and other shapes.

FIG. 12A

represents a top view of the post assembly


1236


as initially formed in the post plane


1204


.

FIG. 12B

represents a perspective view of the post assembly


1236


as configured in one aspect to position the plate


1234


adjacent or connected to a frequency selective surface.





FIG. 13

represents a flowchart of a method for manufacturing an artificial magnetic conductor (AMC). In


1302


, one or more posts or post assemblies are formed in a post plane. The formation of the posts or post assemblies creates one or more voided areas or slots. As previously discussed, the posts may be tabs or projections and the post assemblies may comprise a post and a plate. Stamping, vacuum forming, chemical etching, casting, die-casting, other processes, and a combination of these processes may be used to form the posts or the post assemblies. In


1304


, the posts or post assemblies are operatively disposed adjacent to some or all of the conductive shapes in a frequency selective surface (FSS). In one aspect, the posts or post assemblies are bent or otherwise fashioned to formably extend from the post plane toward the FSS. In the post assemblies, the plates are bent or otherwise fashioned into position adjacent or connected to the FSS. As previously discussed, the posts may be conductively or non-conductively attached to the conductive shapes. The posts may have double shoulders for connection to first and second FSS layers. The plates in the post assemblies may form and may be connected to one or more of the conductive shapes on the FSS. In


1306


, a dielectric layer may be disposed between the post plane and the FSS. A dielectric film may be disposed between the plates and the FSS. As previously discussed, the dielectric film may be part or an extension of the dielectric layer. The dielectric layer and dielectric film may be air and any suitable dielectric material as previously discussed. In


1308


, a backing film may be disposed adjacent to the post plane.




Various embodiments of the invention have been described and illustrated. However, the description and illustrations are by way of example only. Other embodiments and implementations are possible within the scope of this invention and will be apparent to those of ordinary skill in the art. Therefore, the invention is not limited to the specific details, representative embodiments, and illustrated examples in this description. Accordingly, the invention is not to be restricted except in light as necessitated by the accompanying claims and their equivalents.



Claims
  • 1. An artificial magnetic conductor (AMC), comprising:a post plane having at least one post and at least one slot, where the at least one post formably extends from the post plane; and at least one frequency selective surface having at least one conductive shape, where the at least one post is operatively disposed adjacent to the at least one conductive shape.
  • 2. The AMC according to claim 1, where the at least one post comprises a tab.
  • 3. The AMC according to claim 2, where the tab comprises at least one shoulder.
  • 4. The AMC according to claim 3, where:the tab further comprises a pin; the at least one conductive shape forms a hole; and the pin is disposed in the hole.
  • 5. The AMC according to claim 3, where:the at least one frequency selective surface comprises a first FSS layer and a second FSS layer; and the at least one shoulder comprises two shoulders operatively connected to the first and second FSS layers.
  • 6. The AMC according to claim 1, where:the at least one post comprises at least one projection; the at least one voided area comprises at least one slot; and the at least one projection essentially covers the at least one slot.
  • 7. The AMC according to claim 1, where the at least one conductive shape has an essentially rectangular configuration.
  • 8. The AMC according to claim 1, where the at least one conductive shape and the at least one post have essentially the same periodic arrangement.
  • 9. The AMC according to claim 1, where the at least one frequency selective surface further comprises a substrate.
  • 10. The AMC according to claim 1, further comprising a dielectric layer disposed between the post plane and the at least one frequency selective surface.
  • 11. The AMC according to claim 10, where the dielectric layer comprises at least one of a fiber reinforced polymer and a copper laminate epoxy glass.
  • 12. The AMC according to claim 10, where the dielectric layer comprises air.
  • 13. The AMC according to claim 1, further comprising a backing film disposed adjacent to the post plane.
  • 14. The AMC according to claim 1, where the at least one frequency selective surface forms a space between the frequency selective surface and the at least one post.
  • 15. The AMC according to claim 1, where the at least one post comprises a plurality of posts having a period less than the height of the posts.
  • 16. The AMC according to claim 15, where the period is less than or equal to about one-half the height of the posts.
  • 17. The AMC according to claim 1, where the frequency selective surface and the post plane have a curvilinear configuration.
  • 18. The AMC according to claim 1, where the at least one post comprises a plurality of posts having an essentially common angle relative to the post plane.
  • 19. The AMC according to claim 1, where the at least one post forms an angle in the range of about 60 degrees through about 90 degrees relative to the post plane.
  • 20. An artificial magnetic conductor (AMC), comprising:at least one frequency selective surface; and a post plane having at least one post assembly and at least one slot, where each post assembly comprises at least one post and at least one plate, where the at least one post assembly formably extends from the post plane, and where the at least one plate is operatively disposed adjacent to the at least one frequency selective surface.
  • 21. The AMC according to claim 20, where the at least one plate forms a space between the at least one plate and the at least one frequency selective surface.
  • 22. The AMC according to claim 21, where a dielectric film essentially fills the space.
  • 23. The AMC according to claim 20, where the at least one plate is connected to at least one conductive shape on the at least one frequency selective surface.
  • 24. The AMC according to claim 20, where the at least one plate forms at least one conductive shape on the at least one frequency selective surface.
  • 25. The AMC according to claim 20, where the at least one frequency selective surface (FSS) comprises a double-sided FSS having conductive shapes arranged on a bottom layer and a top layer.
  • 26. The AMC according to claim 25, where the at least one plate forms at least one of the conductive shapes on the bottom layer of the double-sided FSS.
  • 27. The AMC according to claim 20, where the at least one plate has an essentially rectangular configuration.
  • 28. The AMC according to claim 20, where the at least one conductive shape and the at least one post assembly have essentially the same periodic arrangement.
  • 29. The AMC according to claim 20, further comprising a dielectric layer disposed between the post plane and the at least one frequency selective surface.
  • 30. The AMC according to claim 20, further comprising a backing film disposed adjacent to the post plane.
  • 31. The AMC according to claim 20, where the at least one frequency selective surface and the post plane have a curvilinear configuration.
  • 32. The AMC according to claim 20, where the at least one post assembly further comprises at least one hinge portion.
  • 33. The AMC according to claim 20, where the at least one plate further comprises at least one open section.
  • 34. The AMC according to claim 33, where the at least one open section comprises three open sections, and where the at least one plate forms a rectangular cloverleaf configuration.
  • 35. The AMC according to claim 20, where the at least one post assembly comprises a plurality of post assemblies having an essentially common angle relative to the post plane.
  • 36. The AMC according to claim 20, where the at least one post assembly forms an angle in the range of about 60 degrees through about 90 degrees relative to the post plane.
  • 37. A method for manufacturing an artificial magnetic conductor (AMC), comprising:forming at least one post and at least one slot in a post plane, where the at least one post formably extends from the post plane; and operatively disposing the at least one post adjacent to at least one frequency selective surface.
  • 38. The method for manufacturing an AMC according to claim 37, further comprising disposing a dielectric layer between the post plane and the frequency selective surface.
  • 39. The method for manufacturing an AMC according t o claim 37, further comprising disposing a backing film adjacent to the post plane.
  • 40. The method for manufacturing an AMC according to claim 37, where forming at least one post further comprises forming a tab.
  • 41. The method for manufacturing an AMC according to claim 40, where forming the tab comprises forming at least one shoulder on the tab.
  • 42. The method for manufacturing an AMC according to claim 41, where forming the tab further comprises forming a pin on the tab.
  • 43. The method for manufacturing an AMC according to claim 42, further comprising disposing the pin in a hole formed by a conductive shape on the at least one frequency selective surface.
  • 44. The method for manufacturing an AMC according to claim 37, where forming at least one post comprises forming a projection and a slot.
  • 45. The method for manufacturing an AMC according to claim 43, where the projection essentially covers the slot on the post plane.
  • 46. The method for manufacturing an AMC according to claim 37, further comprising forming a space between the frequency selective surface and the at least one post.
  • 47. The method for manufacturing an AMC according to claim 37, where forming at least one post comprises forming a plurality of posts having a period less than the height of the posts.
  • 48. The method for manufacturing an AMC according to claim 47, where the period is less than or equal to about one-half the height of the posts.
  • 49. The method for manufacturing an AMC according to claim 37, further comprising forming the frequency selective surface and the post plane into a curvilinear configuration.
  • 50. The method for manufacturing an AMC according to claim 37, further comprising forming the at least one post at an angle in the range of about 60 degrees through about 90 degrees in relation to the post plane.
  • 51. A method for manufacturing an artificial magnetic conductor (AMC), comprising:forming at least one post assembly and at least one slot in a post plane, where each post assembly comprises at least one post and at least one plate, where the at least one post assembly formably extends from the post plane; and operatively disposing the at least one plate adjacent to at least one frequency selective surface.
  • 52. The method for manufacturing an AMC according to claim 51, further comprising forming a space between the at least one frequency selective surface and the at least one plate.
  • 53. The method for manufacturing an AMC according to claim 52, further comprising disposing a dielectric film in the space.
  • 54. The method for manufacturing an AMC according to claim 51, further comprising forming the at least one frequency selective surface and the post plane into a curvilinear configuration.
  • 55. The AMC according to claim 51, further comprising connecting the at least one plate to at least one conductive shape on the at least one frequency selective surface.
  • 56. The AMC according to claim 51, further comprising forming the at least one plate into at least one conductive shape on the at least one frequency selective surface.
  • 57. The AMC according to claim 56, wherethe at least one frequency selective surface (FSS) comprises a double-sided FSS having conductive shapes arranged on a bottom layer and a top layer, and the at least one plate forms at least one of the conductive shapes on the bottom layer of the double-sided FSS.
  • 58. The AMC according to claim 51, where forming the at least one post assembly further comprises forming the at least one plate with at least one open section.
  • 59. The AMC according to claim 20, forming the at least one post assembly at an angle in the range of about 60 degrees through about 90 degrees relative to the post plane.
Parent Case Info

This application is based on Provisional Application Ser. No. 60/271,635, entitled “Artificial Magnetic Conductor System and Method for Manufacturing” and filed on Feb. 26, 2001. The benefit of the filing date of the Provisional Application is claimed for this application.

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Number Date Country
WO 9950929 Oct 1999 WO
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Provisional Applications (1)
Number Date Country
60/271635 Feb 2001 US