초록 ▼

A microstrip antenna configuration employs a metallic patch which is positioned on the top surface of a dielectric substrate. The dielectric substrate has the bottom surface coated with a suitable metal to form a ground plane. A hole is formed through the ground plane, through the dielectric to allo

A microstrip antenna configuration employs a metallic patch which is positioned on the top surface of a dielectric substrate. The dielectric substrate has the bottom surface coated with a suitable metal to form a ground plane. A hole is formed through the ground plane, through the dielectric to allow access to the bottom surface of the patch. A center conductor of a coaxial cable is directly connected to the patch. The center conductor of the coaxial cable is surrounded by a metallic housing within the substrate area. The patch forms a first plate for the capacitance while the diameter of the outer housing of the coaxial cable within the substrate is increased to form another plate on the end of the coaxial cable. The value of capacitance can be adjusted by the area of the metallic housing the relative dielectric constant of the spacing material, and the spacing between the plates. The sum of the probe inductive impedance and microstrip patch antenna input impedance using the direct probe connection is adjusted and centered at a desired design center frequency and many such frequencies can be accommodated.

대표청구항 ▼

What is claimed is: 1. A patch antenna element, comprising: a substrate having a top and bottom surface, a metal patch area positioned on the top surface of said substrate, said patch providing a first capacitor plate, a coaxial cable structure directed through said substrate and having a center co

What is claimed is: 1. A patch antenna element, comprising: a substrate having a top and bottom surface, a metal patch area positioned on the top surface of said substrate, said patch providing a first capacitor plate, a coaxial cable structure directed through said substrate and having a center conductor connected to said metal patch, a conductive housing surrounding said coaxial cable structure within said substrate, with a surface of said housing positioned in proximity to said patch area to form a second capacitor plate, wherein said resultant capacitor formed by said first and second plates is in parallel with the sum of series inductance provided by said coaxial cable structure within said substrate plus input impedance of driven patch. 2. The patch antenna element according to claim 1, wherein said substrate is a foam substrate. 3. The patch antenna element according to claim 1, wherein said coaxial cable structure is selected to be circular or rectangular. 4. The patch antenna element according to claim 1, wherein said substrate has the bottom surface metallized to form a ground plane and wherein said conductive housing is connected to said ground plane. 5. The patch antenna element according to claim 1, wherein said conductive housing is metal. 6. The patch antenna element according to claim 1, wherein said conductive housing is circular. 7. The patch antenna element according to claim 1, wherein said conductive housing is rectangular. 8. The patch antenna element according to claim 1, wherein said conductive housing is elliptical. 9. The patch antenna element according to claim 1, further including a dielectric material surrounding said coaxial cable and located between the inner wall of said conductive housing and the center conductor of said coaxial cable. 10. The patch antenna element according to claim 9, wherein said dielectric is air. 11. A patch antenna comprising: a substrate having a top and a bottom surface, a metal patch positioned on said top surface of said substrate, a coaxial cable structure directed through said substrate with the center conductor of said coaxial cable connected to said patch said coaxial structure center conductor probe having a given inductance, and a housing positioned about said coaxial structure within said substrate to form a parallel capacitance with said patch and with the patch input impedance in series with the inductance of said coaxial cable structure within said substrate to cause a parallel resonance. 12. The patch antenna according to claim 11, wherein said housing surrounds said center conductor of said coaxial cable and is a conductive housing. 13. The patch antenna according to claim 12, wherein the space between said center conductor and said housing is filled with a dielectric material. 14. The patch antenna according to claim 13, wherein said dielectric is air. 15. The patch antenna according to claim 11, wherein said housing is a circular metal housing having a top with an opening to enable said center conductor to pass through and with said housing surface being a capacitor plate, with said patch being the other plate. 16. The patch antenna according to claim 11, wherein said coaxial cable structure is selected from one of the following a square, rectangular, round and elliptical configuration. 17. The patch antenna according to claim 11, wherein said housing is a circular metal housing. 18. The patch antenna according to claim 11, wherein said housing is a rectangular metal housing. 19. The patch antenna according to claim 11, wherein said substrate is a foam substrate. 20. A patch antenna comprising: a substrate having a top and bottom surface, a first metal patch positioned on the top surface of said substrate, a second metal patch positioned within said substrate and below said top surface, a coaxial cable structure directed through said substrate and having a center conductor connected to said second metal patch, a conductive housing surrounding said coaxial cable structure within said substrate, with a surface of said housing positioned in close proximity to said second metal patch to form a capacitor plate with the other plate formed by said first and second patches wherein the resultant capacitor formed is in parallel with the sum of series inductance provided by said coaxial structure within said substrate, and the driven patch input impedance.