Antenna systems and devices and methods of manufacture thereof

Abstract

Embodiments of the present disclosure provide methods, apparatuses, devices and systems related to the implementation of a multi-layer printed circuit board (PCB) radio-frequency antenna featuring, a printed radiating element coupled to an absorbing element embedded in the PCB. The embedded element is configured within the PCB layers to prevent out-of-phase reflections to the bore-sight direction.

Claims

1. A medical device radio-frequency (RF) antenna structure comprising: a printed circuit board (PCB) comprising a plurality of layers; at least one RF antenna comprising a radiating element and a metallic reflector backing the radiating element; an embedded absorbing material disposed within one or more layers internal to the PCB and arranged between the radiating element and the metallic reflector, and an electronic circuit disposed on the PCB, wherein: the electronic circuit is in electrical communication with the at least one RF antenna through one or more of a via and a transmission line in a layer of the PCB; the at least one RF antenna disposed within at least one external layer of the PCB; and the absorbing material is configured to absorb back-lobe radiation from the radiating element.

2. The structure of claim 1, wherein the embedded absorbing material comprises an embedded magnetic material within the PCB.

3. The structure of claim 1, further comprising a conductive structure configured to substantially surround the embedded absorbing material.

4. The structure of claim 3, wherein the conductive structure comprises a row of conductive vias connected to a conductive layer.

5. The structure of claim 1, wherein the electrical circuit comprises RF front-end circuitry.

6. The structure of claim 1, wherein the electrical circuit comprises an RF transceiver.

7. The structure of claim 1, wherein the distance between the radiating element and the metallic reflector is configured to be less than a fourth of the distance of the wavelength of a received RF signal.

8. The structure of claim 1, further comprising one or more openings configured to release gas pressure during a lamination process in producing the PCB.

9. The structure of claim 8, wherein the one or more openings comprise vias, channels and/or slots.

10. The structure of claim 9, wherein the vias comprises at least one of through-hole vias, and blind vias.

11. The structure of claim 8, wherein the one or more openings are filled with a material after gas release.

12. A medical device radio-frequency (RF) antenna structure comprising: a printed circuit board (PCB) comprising a plurality of layers; a transmitting RF antenna comprising a radiating element and a metallic reflector backing the radiating element; a receiving RF antenna; an embedded absorbing material disposed within at least one internal layer of the PCB and arranged between the radiating element and the metallic reflector, and an electronic circuit disposed on the PCB, wherein: the transmitting RF antenna and the receiving RF antenna are disposed within at least one external layer of the PCB, the absorbing material is configured to absorb back-lobe radiation from the radiating element, and the electronic circuit is in electrical communication with the receiving RF antenna and transmitting RF antennas through one or more of a via and a transmission line in a layer of the PCB.

13. The structure of claim 12, wherein the embedded absorbing material comprises an embedded magnetic material within the PCB.

14. The structure of claim 12, wherein at least one of the transmitting antenna and the receiving antenna comprise a wideband directional antenna.

15. The structure of claim 12, wherein the embedded absorbing material comprises a heat resistant absorbing material.

16. The structure of claim 12, further comprising a conductive structure configured to substantially surround the embedded absorbing material.

17. The structure of claim 16, wherein the conductive structure comprises a row of conductive vias connected to a conductive layer.

18. The structure of claim 12, wherein at least one of the layers comprises at least one of ceramic, high temperature polymer impregnated with an RF absorbing material, and ferrite.

19. The structure of claim 12, wherein the electrical circuit comprises impedance matching circuitry.

20. The structure of claim 12, wherein the electrical circuit comprises RF front-end circuitry.

21. The structure of claim 12, wherein the electrical circuit comprises an RF transceiver.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a representation of an antenna front layer, including transmitting and receiving antenna, according to some embodiments;

(2) FIG. 2 shows a representation of a directional antenna with a radiating element backed metallic reflector, according to some embodiments;

(3) FIG. 3 shows a representation of an antenna layers structure, according to some embodiments;

(4) FIG. 4 shows a representation of an antenna layers structure, is to copper contact, according to some embodiments;

(5) FIG. 5 shows a representation of a dissipating material, insight structure, top view, according to some embodiments;

(6) FIG. 6 shows a representation of a component side to antenna transmission line, according to some embodiments;

(7) FIG. 7 shows a representation of a gas release mechanism, according to some embodiments;

(8) FIG. 8 shows a representation of the laminating process stages, according to some embodiments,

(9) FIG. 9 illustrates a representation of a metallic wall or hedge surrounding an absorbing, material, according to some embodiments; and

(10) FIG. 10 shows an example of a delay line implemented with embedded dielectric material, according to some embodiments.

DETAILED DESCRIPTION OF SOME OF THE EMBODIMENTS

(11) FIG. 1 illustrates a representation of an antenna front layer of a PCB structure, including a transmitting and receiving antenna(s), according to some embodiments. The antenna may be a planar antenna comprising a radiator printed on the external layer of the PCB. The antenna (as well as other components included with and/or part of the PCB) may be manufactured from a variety of materials including at least one of, for example, ceramic, polymers (e.g., silicon based or other high temperature resistant polymer), and ferrite. In some embodiments, the shape of the PCB and/or antenna(s) may be optimized so as to enhance at least one of characteristic of the apparatus, including, for example, antenna gain (e.g., at different frequencies in the bandwidth).

(12) In some, embodiments, the antenna may comprise an antenna array 100 which includes a plurality of antennas 102 (e.g., two or more antennas), and one or more of antennas 102 may comprise at least one of a wideband directional antenna(s) and an omnidirectional antenna(s). In the embodiments illustrated in FIG. 1, the antenna array may include at least one transmitting antenna (Tx) for radar pulse transmission, and at least one receiving antenna (Rx). In some embodiments, excitation of an antenna may be achieved via an internal feed line arranged within one of the PCB's layers (as shown in FIG. 6), without use of, for example, any radio-frequency (RF) connectors.

(13) Accordingly, by implementing the antenna and electronics on a single printed circuit board (PCB) structure, a reduction in cost and size can be realized, as well as an elimination of the need for RF connectors.

(14) FIG. 2 illustrates a representation of a directional antenna with a radiating element backed by a metallic reflector according to some embodiments of the disclosure. The directional antenna with a main lobe direction 204 comprises a radiating element 212, which may be positioned at a λ/4 distance 202 from a backed metallic reflector 214 wherein λ represents the wavelength of the RF signal 206. The directional antenna can be configured such that a phase inversion occurs when an RF signal/electromagnetic wave 206 reflects on the reflector 214. In some embodiments, the reflector 214 can comprise a metallic material including at least one of, for example, copper, aluminum, a plated conductive element and/or the like.

(15) In some embodiments, arranging radiating element 212 at a distance λ/4 from the reflector 214, the in-phase reflected waves 210 are coherently summed to signals/waves 208 transmitted from the radiating element 212 and propagated in the opposite direction to that of the reflector 214 direction. In such cases, a maximum efficiency may be achieved by configuring the distance 202 between the radiating element 212 and the reflector 214.

(16) Accordingly, when the reflector 214 is arranged at a distance equivalent to d<<λ/4 (i.e., a distance that is much less than the transmitted RF wavelength's divided by four) such that, the reflected waves 210 are summed out-of-phase with the signals 208 propagated from the radiating element 212, which can substantially degrade the antenna's performance, up to, for example, a full main lobe cancellation.

(17) In some embodiments, where the distance d is <<λ/4, an absorptive material may be arranged between the radiating element 212 and the reflector 214, enabling proper gain performance at the main lobe direction of same embodiments in the ultra-wide band bandwidth, and moreover, may substantially reduce the antenna's thickness. In some embodiments, depending, on the required performance, the thickness of an antenna may be reduced up to a factor of ten or more.

(18) FIG. 3 illustrates a via to conductive layer contact, intended to create a conductive enclosure covering an absorbing material. In some embodiments, a via conductive layer includes an embedded temperature resistant absorbing material. 302, for example, which may comprise magnetically loaded silicon rubber. Such a material can comply with thermal requirements imposed by PCB production processes and assembly of electronic components. For example, the material 302 can be configured to endure the exposure to high temperatures during the production processes; such temperatures can fluctuate between 150° C. and 300° C. depending on the process. In some embodiments, the via conductive layer connection point 306 can be an extension of the conductive cover placed over the embedded absorbing material. 302. In some embodiments, a blind via 304, can be part of the conductive cover placed over the embedded absorbing material. Item 301 also comprises a blind via.

(19) The absorbing material 302 can be used to dissipate back-lobe radiation, can be placed above the antenna radiator layer embedded in the internal layers of the PCB structure. In some embodiments, the shape and thickness of this absorbing material is optimized for example larger dimensions may improve performance for lower frequencies. For example a thicker absorbing material improves performance but increases the antenna's dimensions. The absorbing material may comprise and/or be based on a dissipater made of a ferrite material and/or flexible, magnetically loaded silicone rubber non-conductive materials material such as Eecosorb, MCS, and/or absorbent materials, and/or electrodeposited thin films for planar resistive materials such as Ohmega resistive sheets.

(20) FIG. 4 provides a detailed zoomed-in view of details from FIG. 3, illustrating a representation of an antenna and layered PCB structure according to some embodiments of the disclosure. As shown, the PCB structure may include one or more layers having an embedded absorbing material 402 (or the one or more layers may comprise adsorbing material, with the one more layers being internal to the PCB), and a plurality of additional layers. In some embodiments, the layers can be configured to be substantially flat with little to no bulges. The via holes 404 (e.g., blind vias) may be electrically connected to their target location, via to conductive layer connection point 406 (for example), and may be configured in a plurality of ways including, for example, through-hole vias, blind vias, buried vias and the like. In some embodiments, the absorbing material 404 can be configured to come into contact with the antenna's PCB however this configuration is not essential for the antennas operation.

(21) FIG. 5 illustrates a representation of the internal structure/top-view of a dissipating material according to some embodiments. Specifically, the internal structure of the antenna PCB may comprise an embedded absorbing material. 502 positioned over one or more printed radiating elements (and in some embodiments, two or more), for example, a spiral and/or dipole.

(22) FIG. 6 illustrates a representation of the signal transmission from an electronic circuit to an antenna PCB, according to some embodiments. In some embodiments, a signal can be fed from the electronic components layer 602 in to a blind via 601. Thereafter, the signal can be transmitted through the transmission line 605 (which may comprise of a plurality of layers of the PCB structure), to the blind via 606, and further to transmission line 605 and blind via 601 which feeds a radiating element and/or antenna 604. Additionally, an absorbing layer 603 may be included.

(23) FIG. 7 illustrates a representation of a gas release mechanism, according to some embodiments. For example, the structure may comprise one or more of openings including, for example, a gas pressure release vent or opening 702, another gas pressure release aperture is depicted as 706 configured to release gas pressure during, for example, a lamination process needed to produce the final PCB structure (see description of FIG. 8 below (The lamination process is standard. Embedding materials inside the PCB is rare and we are not aware of venting anywhere. In some embodiments, the one or more openings 702 and 706 may comprise vias, channels and/or slots. In some embodiments, the one or more openings can be filled with a material after the lamination or assembly process, for example with a conducting or a non-conducting material for example: epoxy, conductive or not. Absorbing layer 704 may also be included.

(24) FIG. 8 illustrates a lamination process according to some embodiments of the present disclosure. In such embodiments, a plurality of layers may be laminated. For example, the layers (e.g., groups of layers) represented in FIG. 8 may be laminated in the following order (for example): 802, 806, 804, 808, and 810. One or more, and preferably all, of stacks (items 1-9, i.e., layer 804 and items 10-14, i.e., layer 808) which may include an absorbing material (e.g., in a middle layer), may be laminated together. In the figure, lamination 808, which includes layers 11 and 12, may include an absorbing material. In some embodiments, a last lamination 810 of previous laminations may be performed, and several steps may be implemented in succession to perform this lamination, such as, for example, temperature reduction, and configuring gas flow channels/tunnels (e.g., gas pressure release openings 702, and/or grass pressure release aperture 706 in FIG. 7).

(25) FIG. 9 illustrates a representation of a metallic wall or hedge surrounding an absorbing material, according to some embodiments. As shown, the absorbing material 901 can be surrounded by a metal boundary or hedge 902, configured either as a metallic wall immediately surrounding the absorbing material and/or in direct contact with a plurality of conductive materials (e.g., such as a metallic coating of PCB or rows of conducting vias). In some embodiments, the conductive material can be any conductive material including but not limited to copper, gold plated metal and the like. Such a conductive material can generate a reflection coefficient and/or loss which improves antenna's match to a transmission line via holes placed around the circumference of the buried absorber/dissipater. In some embodiments, a metallic conductive covering layer of (for example) copper and/or gold plated material may be provided above the absorbing material to create a closed electromagnetic cavity structure.

(26) FIG. 10 illustrates an exemplary implementation of a delay line 1006 of a PCB structure 1000, the delay line configured to produce a specific desired delay in the transmission signal between two RF transmission lines 1004 and 1008, implemented with an embedded dielectric material 1010. In some embodiments, basic RF components including, but not limited to, a delay line a circulator and/or a coupler and the like RF components, can be implemented as one or more printed layers within a PCB structure 1000. In some embodiments, this may be accomplished in combination with at least one of a dielectric, magnetic, and absorbing materials embedded in the PCB. Such embedded devices may include, for example, delay lines, circulators, filters and the like. For example, by using high Dk material above delay line, its length can be minimized. Unwanted coupling and/or unwanted radiation reduction can also be achieved by using PCB embedded absorbing or termination material.

(27) Example embodiments of the devices, systems and methods have been described herein. As may be noted elsewhere, these embodiments have been described for illustrative purposes only and are not limiting. Other embodiments are possible and are covered by the disclosure, which will be apparent from the teachings contained herein. Thus, the breadth and scope of the disclosure should not be limited by any of the above-described embodiments but should be defined only in accordance with features and claims supported by the present disclosure and their equivalents. Moreover, embodiments of the subject disclosure may include methods, systems and devices which may further include any and all elements/features from any other disclosed methods, systems, and devices, including any and all features corresponding to antennas, including the manufacture and use thereof. In other words, features from one and/or another disclosed embodiment may be interchangeable with features from other disclosed embodiments, which, in turn, correspond to yet other embodiments. One or more features/elements of disclosed embodiments may be removed and still result in patentable subject matter (and thus, resulting in yet more embodiments of the subject disclosure). Furthermore, some embodiments of the present disclosure may be distinguishable from the prior art by specifically lacking one and/or another feature, functionality or structure which is included in the prior art (i.e., claims directed to such embodiments may include “negative limitations”).

(28) Any and all references to publications or other documents, including but not limited to, patents, patent applications, articles, webpages, books, etc., presented anywhere in the present application, are herein incorporated by reference in their entirety.