DE102017007347A1 - Capacitive interposer for metal slot antenna and method - Google Patents

Abstract

Disclosed is a capacitive interposer having a flexible body that engages a feed slot antenna having a range of bandwidths. Because slot antennas are often fabricated or otherwise integrated into larger structures, the flexible body of the interposer allows the system to fit a variety of surfaces.

Description

CROSS REFERENCE

This application claims priority of US Utility Model Application No. 15 / 657,536 filed on Jul. 24, 2017, which has the benefit of US Provisional Application 62 / 370,362, filed on Aug. 3, 2016, entitled Capacitive Interposer for Metal Slot Antenna, all of which are incorporated herein by reference.

BACKGROUND

Slot antennas have the advantage that they have almost no height, which allows the antenna to be flush with the surface in which it is manufactured. A typical slot antenna provides between 50 MHz and 500 MHz bandwidth, depending on the center frequency, allowing coverage of one or more of wireless technology bands such as RKE, TPMs, Wi-Fi, Bluetooth, and DSRC, depending on the antenna design. Often, the slot antenna is embedded directly or made from the surface of a metallic or other conductive structure, such as a housing of a device or a part of a vehicle body. The slot antenna may be filled or covered with any low permittivity dielectric to be visually hidden.

Slot antenna cables often consist of coaxial cables that are attached by soldering. The precision with which the lead is placed in relation to the radiating slot affects performance. This often requires a complicated device or fixture to ensure proper placement and / or per-unit tuning or adjustment at assembly time. In addition, there are numerous applications of slot antennas for which soldering a cable to the surface thereof is impossible or impractical.

What is needed is a capacitive interposer with a flexible body that provides a simple, reliable and repeatable way of attaching a lead to a slot antenna.

SUMMARY

A capacitive interposer with a flexible body is disclosed for feeding slot antennas having a number of bandwidths. Since slot antennas are often fabricated or otherwise integrated within larger structures, the flexible body of the interposer allows a variety of shapes to be accommodated. The capacitive interposer can be used for any frequency.

The disclosed interposer facilitates a robust, reliable and repeatable coaxial cable feed of a metal slot antenna to a desired delivery location, particularly where soldering a cable to the antenna surface is impractical, impractical, or otherwise undesirable.

Disclosed are flexible capacitive interposers. Suitable flexible capacitive interposers include: a planar, flexible interposer body having a top surface and a bottom surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, wherein the planar, flexible interposer body is attachable to a first end at a first end of a coaxial cable. The planar, flexible interposer body may further comprise a polygon shape adjacent to a second shape, such as a rectangular shape. In some configurations, the planar, flexible interposer body has a circular shape and a second rectangular shape. The first coaxial cable attachment point is positionable on the polygon shape and the second coaxial cable attachment point is positioned on the rectangular shape. The polygon shape has two sets of parallel pages and a set of pages that are not parallel.

Another aspect of the disclosure relates to flexible capacitive interposer systems. Suitable systems include: a coaxial cable having a first end and a second end; and a flexible capacitive interposer having a planar, flexible interposer body having a top surface and a bottom surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, the planar, flexible interposer body being securable on a first side to a first end of a coaxial cable; and a connector attached to the second end of the coaxial cable. The planar, flexible interposer body includes a polygon shape adjacent to another shape, such as a rectangular shape. The planar, flexible interposer body may have a circular shape and a second rectangular shape. The first Coaxial cable attachment point is positioned at the polygon shape and the second coaxial cable attachment point is positioned at the rectangular shape. Further, the polygon shape may have two sets of parallel sides and a set of sides that are not parallel.

Yet another aspect of the disclosure relates to methods of using a flexible capacitive interposer system. Suitable methods include: providing a flexible capacitive interposer having a planar, flexible interposer body having a top surface and a bottom surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, the planar, flexible interposer body being securable on a first side to a first end of a coaxial cable; and connecting a coaxial cable to the flexible capacitive interposer at a first coaxial cable attachment point and a second coaxial cable attachment point; and attaching the adhesive surface of the flexible capacitive interposer at a target location on a surface. The flex may have an alignment where holes therein line up with permanent or temporary alignment pins on a mounting surface to ensure an accurate location of the flex circuitry. In addition, the flexible capacitive interposer can be adapted to a non-planar destination. In addition, removing the flexible capacitive interposer from the target surface and positioning the flexible capacitive interposer at a new destination.

Disclosed are flexible capacitive interposers. Suitable flexible capacitive interposer means include: a planar, flexible interposer body having a top surface and a bottom surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, the planar, flexible interposer body means being attachable to a first end at a first end of a coaxial cable. The planar, flexible interposer body means may further comprise a polygon shape adjacent to a second shape, such as a rectangular shape. In some configuration, the planar, flexible interposer body means has a circular shape and a second rectangular shape. The first coaxial cable attachment point is positionable on the polygon shape and the second coaxial cable attachment point is positioned on the rectangular shape. Further, the polygon shape has two sets of parallel sides and a set of sides that are not parallel.

Another aspect of the disclosure relates to flexible capacitive interposer systems. Suitable systems include: a coaxial cable having a first end and a second end; and a flexible capacitive interposer having a planar, flexible interposer body means having a top surface and a bottom surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, the planar, flexible interposer body means being securable to a first side at a first end of a coaxial cable; and a connector attached to the second end of the coaxial cable. The planar, flexible interposer body means comprises a polygon shape adjacent to another shape, such as a rectangular shape. The planar, flexible interposer body means may have a circular shape and a second rectangular shape. The first coaxial cable attachment point is positioned at the polygon shape and the second coaxial cable attachment point is positioned at the rectangular shape. Additionally, the polygon shape may further include two sets of parallel sides and a set of sides that are not parallel.

Yet another aspect of the disclosure relates to methods of using a flexible capacitive interposer system. Suitable methods include: providing a flexible flexible interposer having a planar, flexible interposer body means having a top surface and a bottom surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, the planar, flexible interposer body means being securable to a first side at a first end of a coaxial cable; and connecting a coaxial cable to the flexible capacitive interposer at a first coaxial cable attachment point and a second coaxial cable attachment point; and attaching the adhesive surface of the flexible capacitive interposer at a target location on a surface. The flex may have an orientation where holes therein line with permanent or temporary alignment pins on a mounting surface to ensure a precise location of the flex circuitry. In addition, the flexible capacitive interposer can be adapted to a non-planar destination. In addition, removing the flexible capacitive interposer from the target surface and positioning the flexible capacitive interposer at a new destination.

RECORDING BY REFERENCE

• US 5,155,493 A erteilt am 13. Oktober, 1992 an Thursby, et al., für Tape type microstrip antenna;
• US 6,054,961 A erteilt am 25. April, 2000 an Gong, et al., für Dual band, glass mount antenna and flexible housing therefor;
• US 6,828,941 B2 erteilt am 07. Dezember, 2004 an King, et al., für Wireless communication device and method;
• US 7,300,863 B2 erteilt am 27. November, 2007 an Pennaz, et al., für Circuit chip connector and method of connecting a circuit chip;
• US 7,504,952 B2 erteilt am 17. März, 2009 an Kaplan, et al., für Wide band RFID system with tag on flexible label;
• US 7,701,352 B2 erteilt am 20. April, 2010 an Forster für RFID label with release liner window and method of making;
• US 8,072,334 B2 erteilt am 06. Dezember, 2011 an Forster, et al., für RFID tag with enhanced readability;
• US 8,441,113 B2 erteilt am 14. Mai, 2013 an Lee für Elimination of RDL using tape base flip chip on flex for die stacking;
• US 8,746,577 B2 erteilt am 10. Juni, 2014 an Bernhard, et al., für Placement insensitive antenna for RFID, sensing and/or communication systems;
• CN 104485522 A erteilt am 11. April, 2015 für Dual-polarized slot coupling antenna;
• WO 2008055578 A1 erteilt am 15. Mai, 2008 an Bohn für Self-adhesive RFID-label and method for the production thereof;
• Laisne, et al., für Robust slot-fed dielectric resonator antenna using an intermediate substrate, Electronics Letters 37. 25: 1497–8 veröffentlicht am 06. Dezember, 2001 ; und
• Ruyle, Small, Dual Band, Placement Insensitive Antennas, Dissertation, University of Illinois at Urbana-Champaign, 2011 .

All publications, patents, and patent applications mentioned in this specification are hereby incorporated by reference to the same extent as if each individual publication, patent, or patent application were expressly and individually indicated as incorporated by reference. See for example

• US 5,155,493 A issued October 13, 1992 to Thursby, et al., for tape type microstrip antenna;
• US 6,054,961 A issued on April 25, 2000 to Gong, et al., for Dual band, glass mount antenna and flexible housing therefor;
• US 6,828,941 B2 issued December 7, 2004 to King, et al., for Wireless communication device and method;
• US 7,300,863 B2 issued November 27, 2007 to Pennaz, et al., for Circuit Chip Connector and Method of Connecting a Circuit Chip;
• US 7,504,952 B2 issued March 17, 2009 to Kaplan, et al., for Wide band RFID system with tag on flexible label;
• US 7,701,352 B2 issued April 20, 2010 to Forster for RFID label with release liner window and method of making;
• US 8,072,334 B2 issued on December 06, 2011 to Forster, et al., for RFID tag with enhanced readability;
• US 8,441,113 B2 issued on May 14, 2013 to Lee for Elimination of RDL using tape base on flip for the stacking;
• US 8,746,577 B2 issued on June 10, 2014 to Bernhard, et al., for Placement insensitive antenna for RFID, sensing and / or communication systems;
• CN 104485522 A issued April 11, 2015 for dual-polarized slot coupling antenna;
• WO 2008055578 A1 issued on May 15, 2008 to Bohn for Self-adhesive RFID label and method for the production thereof;
• Laisne, et al., For Robust slot-fed dielectric resonator antenna using on intermediate substrates, Electronics Letters 37. 25: 1497-8 published December 6, 2001 ; and
• Ruyle, Small, Dual Band, Placement Insensitive Antennas, Dissertation, University of Illinois at Urbana-Champaign, 2011 ,

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with care in the appended claims. A better understanding of the features and advantages of the present invention will become apparent upon reference to the following detailed description, which sets forth illustrative embodiments in which the principles of the invention are utilized, and the accompanying drawings, in which:

1A Figure 3 is a table of exemplary mechanical feature specification and environmental features for a capacitive interposer in accordance with the disclosure;

1B FIG. 4 is a plan view of one embodiment of a capacitive interposer according to the disclosure; FIG. and

2 12 is a schematic drawing of the desired positioning of a capacitive interposer with respect to a typical slot antenna in accordance with the disclosure.

DETAILED DESCRIPTION

Disclosed is a flexible capacitive interposer that provides an electrical interface. The flexible interposer may be used to feed a metal slot antenna to a desired delivery location. The flexible interposer allows coaxial cable feeding of a metal slot antenna. The flexible interposer can be used for applications where soldering or soldering the cable is impractical.

The flexible capacitive interposer is attached to external electronics via a coaxial cable with a standard IPEX connector. The interposer body may be made of flexible polymeric material with adhesive backing to facilitate attachment to the antenna structure. The flexible capacitive interposer may have holes in it that line up with permanent or temporary alignment pins on a mounting surface to ensure an accurate location of the flex circuitry.

1A lists mechanical specifications and environmental specifications for an exemplary interposer according to the disclosure. Details include mechanical parameters and environmental parameters. Exemplary mechanical parameters include dimensions of 29.30mm x 22mm x 0.2mm, flexible polymer material, connectors and cables U.FL and 1.37mm Mini Coax; and a cable length of, for example, up to 100 mm. Other dimensions may be used without departing from the scope of the disclosure. Exemplary environmental specifications include an operating temperature between about -40 ° C and 85 ° C; Storage temperature range between approx. -40 ° C and 85 ° C; relative humidity of about 40% to about 95%; and Restriction of Hazardous Substances (RoH) YES.

1B shows a plan view of one embodiment of a flexible capacitive interposer 100 according to the disclosure. The flexible capacitive interposer 100 includes an interposer body 108 , a coaxial cable 130 and a connector 140 such as an I-PEX Micro RF Coax available from Dai-ichi Seiko Co., Ltd. (Japan). The interposer body 108 is planar and consists of thin, flat, flexible polymer, which allows it to fit different antenna structures. The interposer body 108 has an upper surface 110 and a lower surface (in 1B not shown) opposite to the upper surface 110 on. The lower surface has an adhesive coating that allows the interposer body 108 to attach to an antenna structure. The adhesive coating may be any adhesive suitable for bonding to the structure of a typical slot antenna. Suitable adhesives include, for example, VHB ^™ adhesive tape from 3M ^™ . The installation can be done by a simple "peel-and-stick" process.

In different embodiments of the flexible capacitive interposer 100 can be the shape of the interposer body 108 be defined to facilitate alignment or attachment to different slot antenna structures. In the exemplary embodiment of the flexible capacitive interposer 100 who in 1B is shown has the interposer body 108 a first page 112 , a second page 114 , a third page 116 , a fourth page 118 , a fifth page 120 , a sixth page 122 , a seventh page 124 and an eighth page 126 which are numbered clockwise when viewed from above. The first page 112 is the longest side of the resulting polygon shape of the interposer body 108 , The second page 114 and the eighth page 126 are on opposite sides of the interposer body 108 positioned and have equal side lengths. The second page 114 and the eighth page 126 extend perpendicularly from the respective end of the first page 112 , From the other ends of the second page 114 and the eighth page 126 extend the third page 116 or the seventh page 124 at equal angles θ, as shown, so that the top view of the interposer body 108 compared to the length of the first page 112 rejuvenated. From the other ends of the third page 116 and the seventh page 124 extend the fourth page 118 or the sixth page 122 , which are the same length, at equal angles θ, as shown, so that they are parallel to the second side 114 and the eighth page 126 are. The fifth page 120 runs from the other end of the fourth page 118 to the other end of the sixth page 122 and is parallel to the first page 112 and closes the polygon, which is the shape of the interposer body 108 forms. The resulting polygon has symmetry about the mid-perpendiculars from the center of the first page 112 to the center of the fifth page 120 runs, indicated by a line AA in the illustration. Two coaxial cable attachment points are provided: a first coaxial cable attachment point 170 and a second coaxial cable attachment point 180 , The first coaxial cable attachment point 170 has a rectangular shape and is located in the narrow portion or the bottleneck of the interposer body 108 along the perpendicular bisector of the interposer body 108 , indicated by the line AA in the illustration, between the fourth page 118 and the sixth page 122 , Both the first coaxial cable attachment point 170 as well as the second coaxial cable attachment point 180 is made of copper and is typically made by a metal plating process, although other conductive materials and manufacturing processes can be used. The inner conductor 172 of the coaxial cable 130 is at the interposer body at the first coaxial cable attachment point 170 attached, typically via a surface mounted solder joint, although other methods such as conductive epoxy can be used with suitable electrical and physical properties, reliability and robustness. The coaxial cable 130 itself can also contact the interposer body 108 adhesively bonded to maintain proper guidance and / or strain relief for the conductive connections at the first coaxial cable attachment point 170 and the second coaxial cable attachment point 180 provide.

The second coaxial cable attachment point 180 has a rectangular shape and is located in the wide portion of the interposer body 108 between the second page 114 and the eighth page 126 , The outer conductor 182 of the coaxial cable 130 is at the interposer body 108 at the second coaxial cable attachment point 180 attached, typically via a solder joint, although other methods such as conductive epoxy with suitable electrical and physical properties, reliability and robustness can be used.

To ensure the best antenna performance contains the interposer body 108 Features to facilitate the desired alignment with respect to the slot antenna structure on which it is mounted becomes. Such features may consist of markings, openings or other defining geometry, such as peripheral notches. At the in 1B embodiment shown, the interposer body 108 two alignment features: a first alignment aperture 150 and a second alignment opening 160 , The first alignment opening 150 and the second alignment opening 160 are elliptical, equal in size and located in the broad section of the interposer body 108 , The longitudinal axes of both the first alignment opening 150 as well as the second alignment opening 160 are parallel to the first page 112 of the interposer body 108 , wherein the first alignment opening 150 closer to the first page 112 is positioned as the second alignment opening 160 within the interposer body 108 ,

2 shows the desired positioning of a capacitive interposer with respect to a typical slot antenna according to the disclosure. 2 shows a metallic body 200 with an upper surface or surface 202 , The metallic body 200 may be part of a larger structure or module or arrangement, such as a vehicle body or vehicle frame, or it may be a structure in its entirety. An antenna opening 210 gets into the upper surface of the metallic body 200 worked or otherwise cut or made. The antenna opening 210 consists of a rectangular section 212 and a circular section 214 that cut or overlap so that the resulting shape of the antenna opening 210 a keyhole or lollipop.

On the metallic body 200 there is a capacitive interposer 220 similar to the capacitive interposer used in 1B is described. As in 2 indicated points the capacitive interposer 220 a first coaxial cable attachment point 222 and a second coaxial cable attachment point 224 on, on or at the interposer body 226 are positioned as it is in 1B is described. The interposer body 226 is above the right-angled section 212 the antenna opening 210 positioned so that a line from the center of the first Koaxialkabelanstellungspunkts 222 through the middle of the second coaxial cable attachment point 224 runs, indicated by the line BB in 2 , perpendicular to the long sides of the rectangular section 212 the antenna opening 210 is and that the first coaxial cable attachment point 222 and the second coaxial cable attachment point 224 on opposite sides of the rectangular section 212 rest, causing the antenna opening 210 span. The interposer body 226 is by sticking to the metallic body 200 fixed or attached.

While preferred embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that such embodiments are merely exemplary. Numerous variations, changes, and substitutions will now become apparent to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 5155493 A [0013]
• US 6054961 A [0013]
• US 6828941 B2 [0013]
• US 7300863 B2 [0013]
• US 7504952 B2 [0013]
• US 7701352 B2 [0013]
• US 8072334 B2 [0013]
• US 8441113 B2 [0013]
• US 8746577 B2 [0013]
• CN 104485522 A [0013]
• WO 2008055578 A1 [0013]

Cited non-patent literature

• Laisne, et al., For Robust slot-fed dielectric resonator antenna using on intermediate substrates, Electronics Letters 37. 25: 1497-8 published December 6, 2001 [0013]
• Ruyle, Small, Dual Band, Placement Insensitive Antennas, Dissertation, University of Illinois at Urbana-Champaign, 2011 [0013]

Claims (10)

Flexible capacitive interposer, comprising: a planar, flexible interposer body having an upper surface and a lower surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, wherein the planar, flexible interposer body is attachable to a first end of a coaxial cable on a first side. The flexible capacitive interposer of claim 1, wherein the planar, flexible interposer body has a polygon shape adjacent to a second shape. A flexible capacitive interposer according to any one of the preceding claims, further comprising a slot antenna having a circular shape and a second rectangular shape. The flexible capacitive interposer of claim 2 or 3, wherein the first coaxial cable attachment point is positioned at the polygon shape and the second coaxial cable attachment point is positioned at the second shape and / or wherein the polygon shape has two sets of parallel sides and a set of sides that are not parallel , Flexible Capacitive Interposer System comprising: a coaxial cable having a first end and a second end; and a flexible capacitive interposer with a planar, flexible interposer body having an upper surface and a lower surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, wherein the planar, flexible interposer body is attachable to a first end at a first end of a coaxial cable; and a connector attached to the second end of the coaxial cable. The flexible capacitive interposer system of claim 5, wherein the planar, flexible interposer body comprises a polygon shape adjacent to a rectangular shape. The flexible capacitive interposer system of claim 5 or 6, further comprising a slot antenna having a circular shape and a second rectangular shape. The flexible capacitive interposer system of claim 6 or 7, wherein the first coaxial cable attachment point is positioned at the polygon shape and the second coaxial cable attachment point is positioned at the rectangular shape and / or wherein the polygon shape comprises two sets of parallel sides and a set of sides, that are not parallel. A method of using a flexible capacitive interposer system, comprising: Providing a flexible capacitive interposer with a planar, flexible interposer body having an upper surface and a lower surface and a plurality of sides; an adhesive surface positioned on at least one of the upper surface and the lower surface; a first coaxial cable attachment point and a second coaxial cable attachment point positioned on the planar, flexible interposer body, wherein the planar, flexible interposer body is attachable to a first end at a first end of a coaxial cable; and Connecting a coaxial cable to the flexible capacitive interposer at a first coaxial cable attachment point and a second coaxial cable attachment point; and Attaching the adhesive surface of the flexible capacitive interposer at a destination on a surface. The method of claim 9, further comprising the step of: Adapting the flexible capacitive interposer to a non-planar destination; and or Removing the flexible capacitive interposer from the target surface and positioning the flexible capacitive interposer at a new target location.

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