Directional stripline structure and manufacture

Claim 1

A method for fabricating directional couplers comprising a pair of spaced striplines, comprising the steps of: forming first and second metallic striplines on opposite sides of an interior insulative substrate, each said stripline having a first and a second port disposed substantially adjacent to a selected edge of said substrate; forming first and second external substrates each comprising an insulative board with one side thereof metallically coated; laminating said external substrates to respective sides of said interior substrate, with the location of said ports being in a known and predetermined planar coordinate relationship with respect to access points on the metallic surfaces of said external substrates; forming holes through said laminated assembly at said access points; metallically plating through said holes, thereby to effect electrical connection between said respective ones of said plated holes and the corresponding one of said ports of said interior substrate; and etching a region around the plated through-hole entrance at each access point to form a metal pad extending from said entrance to said edge of said substrate to electrically isolate said hole entrance from the surrounding metallic coating.

Claim 2

A method for fabricating directional couplers comprising a pair of spaced striplines, comprising the steps of: forming first and second metallic striplines on opposite sides of an interior insulative substrate, each said stripline having a first and a second port disposed substantially adjacent to a selected edge of said substrate; forming first and second external substrates each comprising an insulative board with one side thereof metallically coated; laminating said external substrates to respective sides of said interior substrate, with the location of said ports being in a known and predetermined planar coordinate relationship with respect to access points on the metallic surfaces of said external substrates; forming holes through said laminated assembly at said access points; metallically plating through said holes, thereby to effect electrical connection between said respective ones of said plated holes and the corresponding one of said ports of said interior substrate; and etching a region around the plated through-hole entrance at each access point to form a metal pad extending from said entrance to said edge of said substrate to electrically isolate said hole entrance from the surrounding metallic coating.

Claim 9

The method according to claims 1,3, or 5, comprising the further steps of placing a sheet of heat-actuated adherent material between the internal substrate and each of said two external substrates, bringing all said substrates together, and applying heat.

Claim 10

A method for manufacturing a circuit board comprising one or more directional couplers, comprising the steps of: forming first and second metallic striplines on opposite side of an interior insulative substrate, each said stripline having a first and a second port; forming first and second external substrates each comprising an insulative board with one side thereof metallically coated; laminating said exteranl substrates to respective sides of said interior substrate, with the location of said ports being in a known and predetermined planar coordinate relationship with respect to access points on the metallic surfaces of said external substrats; forming holes through said laminated assembly at said access points; metallically plating through said holes, thereby to effect electrical connection between said respective ones of said plated holes and the corresponding one of said ports of said interior substrate; etching a region around the plated through-hole entrance at each access point to electrically isolate said hole entrance from the surrounding metallic coating, thereby to create along an edge of said exterior substrates a connection pad for each said plated through-hole; and vertically affixing the resulting said directional coupler to a mother-board comprising ground metallic regions and circuit paths, by solder connections of said coupler pads to said circuit paths on said mother-board and by solder connection of said ground planes of said exterior substrates to said metallic regions of said motherboard.

Claim 11

A method for manufacturing a circuit board comprising one or more directional couplers, comprising the steps of: forming first and second metallic striplines on opposite side of an interior insulative substrate, each said stripline having a first and a second port; forming first and second external substrates each comprising an insulative board with one side thereof metallically coated; laminating said exteranl substrates to respective sides of said interior substrate, with the location of said ports being in a known and predetermined planar coordinate relationship with respect to access points on the metallic surfaces of said external substrats; forming holes through said laminated assembly at said access points; metallically plating through said holes, thereby to effect electrical connection between said respective ones of said plated holes and the corresponding one of said ports of said interior substrate; etching a region around the plated through-hole entrance at each access point to electrically isolate said hole entrance from the surrounding metallic coating, thereby to create along an edge of said exterior substrates a connection pad for each said plated through-hole; and vertically affixing the resulting said directional coupler to a mother-board comprising ground metallic regions and circuit paths, by solder connections of said coupler pads to said circuit paths on said mother-board and by solder connection of said ground planes of said exterior substrates to said metallic regions of said motherboard.