TUNABLE HIGH IMPEDANCE SURFACE DEVICE

• US 20080150657A1
• Filed: 12/26/2006
• Published: 06/26/2008
• Est. Priority Date: 12/26/2006
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Dunn, Gregory J., Savic, Jovica, Svigelj, John A.
• Granted Patent: US 7,518,465 B2
• Time in Patent Office: Days
• US Class Current: 333/262
• CPC Class Codes: H01G 5/18 due to change in inclination, e.g. by flexing, by spiral wrapping
• CPC Class Codes: H01Q 15/0066 said selective devices being reconfigurable, tunable or controllable, e.g. using switches
• CPC Class Codes: H01Q 15/147 provided with means for controlling or monitoring the shape of the reflecting surface for scanning H01Q3/01; aerials or aerial systems providing multiple beamwidths H01Q25/002
• CPC Class Codes: H05K 1/116 Lands, clearance holes or other lay-out details concerning the surrounding of a via
• CPC Class Codes: H05K 1/162 incorporating printed capacitors
• CPC Class Codes: H05K 2201/0195 Dielectric or adhesive layers comprising a plurality of layers, e.g. in a multilayer structure
• CPC Class Codes: H05K 2201/09109 Locally detached layers, e.g. in multilayer
• CPC Class Codes: H05K 2201/09436 Pads or lands on permanent coating which covers the other conductors
• CPC Class Codes: H05K 2201/096 Vertically aligned vias, holes or stacked vias
• CPC Class Codes: H05K 3/0023 by exposure and development of a photosensitive insulating layer
• CPC Class Codes: H05K 3/4652 Adding a circuit layer by laminating a metal foil or a preformed metal foil pattern H05K3/4647 takes precedence
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

A tunable high impedance surface device (100) includes a conductive ground plane (105) and a plurality of conductive elements (110-114) electrically connected to the conductive ground plane (105). The device (100) also includes a plurality of capacitive elements (120-124) operable to vary a predetermined electromagnetic characteristic of the apparatus and standoffs (130, 132) between the plurality of capacitive elements (120-124) and the plurality of conductive elements (110-114). In one form, laser-drilled and electrically conductive micro-vias (136, 138) extend through the standoffs (130, 132) thereby electrically connecting the plurality of capacitive elements (120-124) to a data bus (140). The capacitive elements (120-124) may be integral with a circuit board (144) that supports the plurality conductive elements (110-114). Either the capacitive elements (120-124) or the conductive elements (110-114) are mechanically flexible and selectively movable to controllably adjust the distance (142) between the capacitive and conductive elements.

Claims

1. An tunable high impedance apparatus comprising:

a conductive ground plane;

a plurality of conductive elements electrically connected to the conductive ground plane;

a plurality of capacitive elements disposed at a predetermined position relative to the conductive elements to allow for a predetermined electromagnetic characteristic to be controllably varied;

standoffs between the plurality of capacitive elements and the plurality of conductive elements; and

electrically conductive micro-vias extending through the standoffs electrically connecting the plurality of capacitive elements to a data bus.

2. The apparatus of claim 1 wherein the capacitive elements are spaced by a distance from the conductive elements, and at least one of a group comprising the plurality of conductive elements and the plurality of capacitive elements are mechanically flexible and selectively movable to adjust the distance between the plurality of capacitive elements and the plurality of conductive elements to controllably vary the predetermined electromagnetic characteristic.

3. The apparatus of claim 1 including a primary circuit board having the conductive ground plane and the plurality of conductive elements disposed on opposite sides thereof.

4. The apparatus of claim 3 further comprising at least two mounts affixed to the primary circuit board with at least one of the mounts being movable.

5. The apparatus of claim 4 wherein the at least one movable mount comprises a piston movable relative to the primary circuit board to controllably deform the primary circuit board.

6. The apparatus of claim 3 wherein the plurality of capacitive elements are disposed on secondary circuit boards.

7. The apparatus of claim 6 wherein the secondary circuit boards are secured to the primary circuit board through the standoffs.

8. The apparatus of claim 6 wherein the secondary circuit board comprises a laser-scribed polyimide flex material.

9. The apparatus of claim 1 wherein the standoffs comprise cured photodielectric material disposed between the primary circuit board and a portion of one of the plurality of capacitive elements.

10. The apparatus of claim 3 further comprising a plurality of conductive vias extending through the primary circuit board for connecting the plurality of capacitive elements to the data bus.

11. The apparatus of claim 1 wherein each of the plurality of capacitive elements is spaced from an underlying one of the conductive elements by a predetermined distance and shaped to substantially match at least a portion of an outer edge of the underlying conductive element.

12. The apparatus of claim 2 wherein the distance is selectively adjustable to be between approximately zero thousandths of an inch and approximately twelve thousandths of an inch.

13. The apparatus of claim 2 wherein the data bus can selectively apply an electrical charge to at least some of the plurality of capacitive elements to create a potential difference between the at least some of plurality of capacitive elements and the conductive elements disposed relative to the at least some of plurality of capacitive elements such that the distance between the plurality of conductive elements and the plurality of capacitive elements is selectively adjusted.

14. A method of making a tunable high impedance apparatus comprising a ground plane on a first side of a primary circuit board electrically connected to a plurality of conductive elements on a second side of the primary circuit board, the method comprising:

applying a photodielectric layer to the second side of the primary circuit board;

exposing the photodielectric layer to render a first region soluble and a second region insoluble;

affixing a secondary circuit board to the photodielectric layer;

drilling through the secondary circuit board and photodielectric layer forming a conductive micro-via therethrough;

etching the secondary circuit board to shape conductive layer portions spaced above at least one of the plurality of conductive elements;

developing the photodielectric layer to remove at least a substantial portion of the first region of the photodielectric layer.

15. The method of claim 14 wherein the secondary circuit board and photodielectric layer are drilled by directing a laser to drill through the secondary circuit board and photodielectric layer and curing at least a portion of the second region of the photodielectric layer adjacent to the conductive micro-via with the laser during said drilling therethrough.

16. The method of claim 14 wherein developing the photodielectric layer to remove at least a substantial portion of the first region of the photodielectric layer further comprises removing at least a portion of the photodielectric layer between the primary circuit board and at least one of the conductive layer portions.

17. The method of claim 14 further comprising mounting the primary circuit board to a plurality of mounts wherein at least one of the plurality of mounts is selectively movable to controllably deform the primary circuit board.

18. An apparatus comprising:

a conductive ground plane disposed on a first side of a circuit board;

a plurality of conductive elements disposed on a second side of the circuit board and electrically connected to the conductive ground plane;

a second plurality of conductive elements that are spaced relative to the second side of the circuit board and adjacent to at least two of the plurality of conductive elements thereon;

integral standoffs disposed on the second side of the circuit board and affixed to the second plurality of conductive elements for supporting and integrating the second plurality of conductive elements to the circuit board.

19. The apparatus of claim 18 wherein at least one of a group comprising the plurality of conductive elements and the second plurality of conductive elements is mechanically flexible and selectively movable to adjust a distance between the plurality of conductive elements and the second plurality of conductive elements.

20. The apparatus of claim 18 further comprising laser-drilled and electrically conductive micro-vias electrically connecting the second plurality of conductive elements through the integral standoffs to a second plurality of conductive vias in the circuit board connected to a data bus.