Abstract
A waveguide assembly which includes an elongated waveguide element (1) and a connector body (2). The connector body (2) is connected to an end of the elongated waveguide element (1) and has a substantially planar bottom surface (24) and an opposing top surface (23). The connector body is made from a single piece of partially metallized dielectric. The connector body has a waveguide coupling element (21) adjacent to the elongated waveguide element (1). The connector body further has an arrangement of electromagnetic band gap elements (27) adjacent to the waveguide coupling element (21).
Claims
1. A waveguide assembly comprising: a) an elongated waveguide element; and b) a connector body, the connector body being connected to an end of the elongated waveguide element; the connector body having a substantially planar bottom surface and an opposing top surface and being made from a single piece of partially metallized dielectric; the connector body having a waveguide coupling element adjacent to the elongated waveguide element; and further an arrangement of electromagnetic band gap elements adjacent to the waveguide coupling element, wherein the electromagnetic band gap elements are recesses, the recesses extending in the connector body from the top surface towards the bottom surface.
2. The waveguide assembly according to claim 1, wherein the waveguide element is made from metallized dielectric.
3. The waveguide assembly according to claim 1, wherein all surfaces of the connector body other than the bottom surface are fully metallized.
4. A method for electromagnetic signal transmission, the method including transmitting the electromagnetic signal via a waveguide assembly according to claim 1.
5. The waveguide assembly according to claim 1, wherein the recesses have a cross-shaped cross section.
6. The waveguide assembly according to claim 1, wherein the recesses extend parallel to each other.
7. The waveguide assembly according to claim 1, wherein the recesses are arranged in a pattern of rows and columns.
8. The waveguide assembly according to claim 1, wherein the recesses extend perpendicular to the bottom surface.
9. The waveguide assembly according to claim 1, wherein the elongated waveguide element projects perpendicular from the top surface and/or the bottom surface.
10. The waveguide assembly according to claim 1, wherein the end of the elongated waveguide element is connected to a circumferential side surface of the connector body, the circumferential side surface connecting the top surface and the bottom surface.
11. The waveguide assembly according to claim 1, further including an arrangement of elongated fixation elements, the elongated fixation elements projecting from the bottom surface.
12. The waveguide assembly according to claim 1, including a non-conductive adhesive element, the non-conductive adhesive element covering at least part of the bottom surface.
13. The waveguide assembly according to claim 1, further including a conductive adhesive element, the conductive adhesive element covering an area of the bottom surface.
14. The waveguide assembly according to claim 1, wherein the elongated waveguide element is branched.
15. The waveguide assembly according to claim 1, further including a printed circuit board with a board-integrated waveguide, wherein the bottom surface of the connector body is mounted on the printed circuit board in a planar manner such that electromagnetic waves are guided between the elongated waveguide element and the board-integrated waveguide via the connector body.
16. A waveguide assembly comprising: a) an elongated waveguide element; and b) a connector body, the connector body being connected to an end of the elongated waveguide element; the connector body having a substantially planar bottom surface and an opposing top surface and being made from a single piece of partially metallized dielectric, wherein the end of the elongated waveguide element is connected to a circumferential side surface of the connector body, the circumferential side surface connecting the top surface and the bottom surface; the connector body having a waveguide coupling element adjacent to the elongated waveguide element; and further an arrangement of electromagnetic band gap elements adjacent to the waveguide coupling element.
17. The waveguide assembly according to claim 16, further including an arrangement of elongated fixation elements, the elongated fixation elements projecting from the bottom surface.
18. The waveguide assembly according to claim 16, wherein all surfaces of the connector body other than the bottom surface are fully metallized.
19. A waveguide assembly comprising: a) an elongated waveguide element, wherein the elongated waveguide element is branched; and b) a connector body, the connector body being connected to an end of the elongated waveguide element; the connector body having a substantially planar bottom surface and an opposing top surface and being made from a single piece of partially metallized dielectric; the connector body having a waveguide coupling element adjacent to the elongated waveguide element; and further an arrangement of electromagnetic band gap elements adjacent to the waveguide coupling element.
20. The waveguide assembly according to claim 19, further including an arrangement of elongated fixation elements, the elongated fixation elements projecting from the bottom surface.
Description
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
(1) FIG. 1 shows an embodiment of a waveguide assembly in accordance with the present disclosure in a side view;
(2) FIG. 2 shows the embodiment of FIG. 1 in a sectional view;
(3) FIG. 3 shows the embodiment of FIG. 1 in a detailed top view;
(4) FIG. 4 shows the embodiment of FIG. 1 in a detailed bottom view;
(5) FIG. 5 shows a further embodiment of a waveguide assembly in accordance with the present disclosure in a top view;
(6) FIG. 6 shows the embodiment of FIG. 1 in a cross sectional view;
(7) FIG. 7 shows the embodiment of FIG. 5 in a detailed perspective bottom view;
(8) FIG. 8 shows a further embodiment of a waveguide assembly in accordance with the present disclosure in a detailed bottom view;
(9) FIG. 9 shows the embodiment of FIG. 5 in a detailed exploded perspective view together with further elements;
(10) FIG. 10 shows a side view corresponding to FIG. 9;
(11) FIG. 11 shows a still further embodiment of a waveguide assembly in accordance with the present disclosure; and
(12) FIG. 12 exemplarily illustrates the high-frequency transmission performance of a waveguide assembly in accordance with the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
(13) In the following, reference is first made to FIG. 1 to FIG. 4, showing a first embodiment of a waveguide assembly in accordance with the present disclosure, where like features are denoted by the same reference labels in FIGS. 1-4. FIG. 1 shows a side view, FIG. 3 and FIG. 4 show a detailed top view respectively bottom view. FIG. 2 shows a sectional view along line D-D as indicated in FIG. 1.
(14) In FIG. 2, a Cartesian coordinate system (i.e., x, y, z) is shown that indicates the directions as used in the description. Similarly, a Cartesian coordinate system is shown in FIG. 6, a further embodiment as described further below. The direction from bottom to corresponds to the y-direction and the x-direction and z-direction directions that are perpendicular to the y-direction are referred to as “lateral” directions. It is noted that directional terms such as “left”, “right”, “top”, or “bottom”, “above”, or “below” are intended to aid the reader's understanding and do not imply any particular orientation in a situation of use. The same holds true for the use of such terms in the summary of the invention above.
(15) The waveguide assembly includes an elongated waveguide element 1 (shown in part) and the connector body 2. The connector body 2 substantially has the shape of a disc with square top and bottom view (FIGS. 3, 4). As best visible in FIG. 1 and FIG. 2, the connector body 2 has a waveguide coupling element 21 that is realized as solid block, extends to a bottom surface 24 and is arranged in the center of the connector body 1. The top surface of the waveguide coupling element 21 is connected to the end 11 of the elongated waveguide element 1.
(16) As best visible in FIG. 3, the waveguide coupling element 21 is surrounded by an arrangement of electromagnetic band gap elements on all of the four sides in the top view. The electromagnetic band gap elements extend as recesses 27 of exemplary cross-shaped cross section from the top surface 23 towards the bottom surface 24. The recesses 27 are exemplarily arranged in a 5×5 matrix and equally spaced apart from each other, with the constant distance between the single rows and columns. A number of recesses in the center of the connector body 2, however, is omitted because of the waveguide coupling element 21.
(17) The dielectric that is present between the recesses 27 forms an arrangement of pillars 22 with substantially circular cross sections, and link elements in a form of thin walls 26 that connect neighboring pillars 22 in both lateral directions.
(18) As best visible in FIG. 2 and FIG. 6, the recesses 27 have a recess ground 27a above the bottom surface. Consequently, the connector body 2 has a thin, disc-shaped base part 2′ from which the pillars 22 and walls 26 perpendicularly project to the top surface 23. As best visible in FIG. 3, the rows and columns of pillars 22, walls 26 and recesses are centered with respect to each other. The circumferential side surface or shell surface 25 of the connector body 2 is smooth and non-rocked respectively non-corrugated.
(19) As best visible in FIG. 2 and FIG. 4, a number of four elongated fixation elements 3 projects from the bottom surface 24, with one of the fixation elements 3 being arranged in each corner of the connector body 2. The elongated fixation elements 3 are exemplarily shown as snap fit elements that are designed to snap fit into corresponding holes or bores of a PCB as further high-frequency device (not shown), thereby establishing a tight connection with pressing contact between the bottom surface 24 and a top surface of the PCB as a counter surface. In this example, the elongated waveguide element 1 and the connector body 2 are realized from a single piece of plastic in an integral way. The end 11 of the elongated waveguide element 1 accordingly extends continuously into the waveguide coupling element 21. The connector body 2 is fully metallized except from the bottom surface 24 which is non-metallized in order to allow electromagnetic wave transition. In particular the surface of the waveguide coupling element 21 and the inner surface and grounds of the recesses 27, as well as the top surface 23 and the circumferential side surface 25 are metallized. In the following, reference is additionally made to FIGS. 5, 6, 7, and 9 and 10, showing a further embodiment of a waveguide assembly in accordance with the present disclosure, where like features are denoted by the same reference labels in FIGS. 5-10. FIG. 5 shows a top view. FIG. 6 shows a cross sectional view along line D-D as indicated in FIG. 5. FIG. 7 shows a detailed perspective bottom view of the connector body 2. FIG. 9 shows a perspective exploded view and FIG. 10 shows a detailed side view together with further elements as discussed further below.
(20) In this embodiment, the connector body 2 is designed somewhat differently in comparison with the before-described embodiment, with the following description focusing on the differences. Further in this embodiment, a connector body 2 of identical design is exemplarily arranged at both ends 11 of the elongated waveguide element. In this embodiment, the elongated waveguide element 1, at end 11, is connected to the circumferential side surface 25. The waveguide coupling element 21 further extends to the circumferential side surface 25, such that the elongated wave guide element 1 extends continuously into the waveguide coupling element 21.
(21) As best visible in FIG. 5 and FIG. 9, three sides of the waveguide coupling element 21 are adjacent to the electromagnetic band gap structure as explained before, with the end 11 of the elongated waveguide element 1 being connected the waveguide coupling element 21 at the remaining fourth side. As compared to the embodiment of FIG. 1 to FIG. 4, the overall design is accordingly slimmer, with the overall height being defined by the height of the connector body 2.
(22) Because no electromagnetic band gap elements can be arranged at the side of the connector body 2 where the waveguide coupling element 21 is arranged and the elongated wave guide element 1 is connected, alternative measures are foreseen in order to ensure the desired guiding of electromagnetic waves and prevent undesired wave propagation. As seen in FIG. 6, a conductive adhesive element in form of a conductive adhesive strip 4 is arranged along an edge of the bottom surface 24 that extends below the waveguide coupling element 21. The metallization of the connector body 2 extends into the contact area with the conductive adhesive strip 4; favorably, the whole contact are is metallized in order to ensure good areal galvanic coupling with the metallization 62 (FIGS. 9 and 10). The remaining area of the bottom surface 24 that is not covered by the adhesive conductive strip 4, in contrast, is not metallized.
(23) It is noted that instead of a conductive adhesive element, other ways of galvanic coupling may be provided. By way of example, the bottom surface 24 may be metallized in the area of the waveguide coupling element 21 and be galvanic coupled with the PCB may be established by way of a pressing contact between the bottom surface 24 and the PCB 6. Conductive spring elements between the bottom surface 24 and the PCB 6, and/or a micro structuring of the bottom surface 24 may be present in the area of the waveguide coupling element 21. In the exploded view of FIG. 9 and the side view of FIG. 10, the elongated waveguide element 1 and the connector body 2 are shown together with a PCB 6 as exemplary further high-frequency device. The PCB 6 is generally designed as known in the art, including a carrier 61 which may, e.g, be made from FR4, and a structured metallization 62 on a top surface. The structured metallization 62 includes a slit 63 which corresponds to the end of a board-integrated waveguide (not visible) as explained in the general description. The slit 63 and the end of the board-integrated waveguide are arranged in alignment and under the waveguide coupling element 21. Electromagnetic waves may accordingly exit the bottom surface of the connector body 2 respectively the waveguide coupling element 21 and enter the board-integrated waveguide via the slit 63, or the other way around. Undesired lateral wave propagation is prevented by way of the electromagnetic band gap structure and the conductive adhesive element 4.
(24) In order to ensure a good areal contact between the bottom surface 24 of the connector body 2 and the PCB 6, respectively, metallization 62 of a non-conductive adhesive element in form of a non-conductive adhesive layer 5 is provided between the bottom surface 24 and the metallization 62. The non-conductive adhesive layer 5 has favorably the same thickness as the conductive adhesive strip 4 and bridges the gap between the bottom surface 24 and the metallization 62 that would otherwise result from the presence of the adhesive strip 4 as explained before. The non-conductive adhesive layer 5 is permeable for electromagnetic waves.
(25) In addition, the non-conductive adhesive layer 5 serves for fixing the connector body 2 on the PCB 6, in addition to the snap fit fixation elements 3. In a variant, the snap fit fixation elements 3 may be omitted and the connector body 2 adhesively fixed on the PCB 6 only.
(26) A PCB 6 of substantially the same design may also be used in other embodiments, for example together with a connector body as shown in FIG. 1 to FIG. 4.
(27) In the following, reference is additionally made to FIG. 8, showing a detailed perspective bottom view of the connector body 2 according to a further exemplary embodiment. This embodiment is generally similar to the before-described embodiment. In contrast to the the before-described embodiment, however, the elongated fixation elements are realized as plastically deformable posts 3′ that deform plastically upon being inserted into corresponding bores of holds of a counter surface. Those plastically deformable posts 3′ may also be used in other embodiments, for example the embodiment is generally shown in FIG. 1 to FIG. 4. In a variant, the posts 3′ are conductive and establish the galvanic coupling of the metallization of the bottom surface 24 in the area of the waveguide coupling element, and the PCB metallization 61. Those conductive posts may replace or be present instead of the conductive adhesive strip 4 as explained before.
(28) In the following, reference is additionally made to FIG. 11. FIG. 11 shows a still further embodiment of a waveguide assembly in accordance with the present disclosure. In the shown example, the connector body 2 is designed in accordance with FIG. 5 to FIG. 10 as discussed before. The connector body 2 may, however, also be designed in accordance with another embodiment, for example in the embodiment of FIG. 1 to FIG. 4. The embodiment of FIG. 11 differs from the before-discussed embodiment in that the elongated waveguide element 1 is branched, having four branches 1a, 1b, 1c, 1d. While only branch 1d is shown as connected to a connector body 2, some or all of the other branches 1a, 1b, 1c may also each be connected to a connector body. However, branches may also be connected to further high-frequency components in a different way. Furthermore, by way of example, the metallization (not separately referenced) of the elongated waveguide element 1 is discontinuous, with the metallization being omitted in a strip-shaped area 12 of branch 1a. Through the non-metallized area 12, electromagnetic waves may enter and/or except branch 1a, thereby serving as antenna.
(29) In the following, reference is additionally made to FIG. 12. FIG. 12 exemplarily illustrates the high-frequency transmission performance (i.e. S-Parameter) of a waveguide assembly attached to a microstrip transmission line on an PCB with a slit 63 explained in FIG. 9 in accordance with the present disclosure. In FIG. 12, curves A and B show the return loss (Y1) in both directions for a frequency range (Freq[GHz]) of 50 GHz to 70 GHz with reference to the decibel scale on the left side of the diagram. Curve C shows the transmission attenuation for the same frequency rate with reference to the right scale (Y2). FIG. 12 shows that the transmission performance is good, with low loss and good match over an operational bandwidth of more than 20%. Furthermore the electrical behavior is very robust against displacement of the connector to the PCB in X, Y and Z direction.
