The disclosure relates generally to electromagnetic waveguides and more particularly to dielectric waveguide components that are mountable on a substrate.
Electromagnetic waveguides generally comprise a metallized conduit that defines boundaries within which the propagation of energy is constrained. Dielectric filled waveguides are often used for higher frequency applications, like microwaves. The geometry of the waveguide affects characteristics of the waveguide like impedance, cutoff frequency and propagation mode. Waveguides can be configured as couplers, polarizers, and filters among other circuit elements in small-scale radio frequency (RF) and microwave systems. These and other waveguide systems often require mounting of a waveguide component on a printed circuit board (PCB) for transitioning to coplanar, microstrip, stripline or other impedance controlled transmission lines. To facilitate such integration, micros trip transmission lines sometimes include a widening apron that forms a transition for interfacing with the waveguide. It's also known to provide a tapered spacing between conductive posts in substrate integrated waveguides (SIW) to form a narrowing transition for interfacing with a coplanar transmission line. The transition interface between waveguide components and impedance controlled transmission lines however tends to be a source of impedance mismatch or reduced bandwidth and may require increased component size.
The objects, features and advantages of the present disclosure will become more fully apparent to those of ordinary skill in the art upon careful consideration of the following Detailed Description and the appended claims in conjunction with the accompanying drawings described below.
The present disclosure relates generally to electromagnetic waveguides mountable on a substrate like a printed circuit board (PCB) as described further herein. Such waveguides can be configured as a coupler, a polarizer, resonator, or filter among other electrical components for use in small-scale radio frequency (RF) systems or subassemblies. The term “radio frequency” as used herein includes microwaves.
The waveguide generally comprises a dielectric substrate, also referred to herein as a dielectric, having at least partially conductive portions that define boundaries within which propagating radio frequency energy is confined. The dielectric can comprise a ceramic, glass, or plastic among other materials and compositions having suitable permittivity and other characteristics. The conductive portions can be metallized surfaces of the dielectric substrate formed by selectively applying metal or other conductive material on portions of the dielectric substrate. The metal can be a base metal, precious metal, metal alloy or some other conductive material. Metals can be applied by sputtering, plating or other known or future deposition processes. The conductive material can also be conductive sheet material layered onto the dielectric.
Characteristics of the waveguide depend on its geometry as well as dielectric material properties. For example the cutoff frequency is a function of spacing between the side conductors, i.e., a width of the waveguide, dielectric constant of the substrate material, and impedance is a function of the spacing or height between the conductors on the upper and lower surfaces of the waveguide.
One such waveguide is a transverse electric (TE) mode waveguide. In
In
The first and second side conductors of the waveguide can be implemented in any one of many different forms. In
The waveguide also comprises a conductive excitation member at one or both ends thereof. In some implementations, the signal is introduced at an input of the waveguide and extracted at an output of the waveguide. Generally, the excitation member is electrically coupled to the conductor and is disposed through or across a portion of the dielectric at or near an end surface of the dielectric that is devoid of conductive material, wherein portions of the end surface, on opposite sides of the conductive excitation member, are devoid of conductive material. The excitation member also includes a host interface electrically isolated from the ground plane and connectable to a transmission line on a host device.
In
In some implementations, the waveguide includes one or more lateral conductors interconnecting the conductive member and the ground plane. The one or more lateral conductors are disposed on or near the same end surface portion of the dielectric where the conductive excitation member is located, wherein at least a portion of the first end surface portion of the dielectric is devoid of conductive material between the one or more lateral conductors and the conductive excitation member. An input impedance of the waveguide is a function of the one or more lateral conductors and the size of the excitation member. In implementations including first and second lateral conductor, the conductive excitation member can be located between the first and second lateral conductors. In
In
While the present disclosure and what is presently considered to be the best mode thereof has been described in a manner establishing possession by the inventors and enabling those of ordinary skill in the art to make and use the same, it will be understood and appreciated that equivalents of the exemplary embodiments disclosed herein exist, and that myriad modifications and variations may be made thereto, within the scope and spirit of the disclosure, which is to be limited not by the exemplary embodiments described but by the appended claims.
The present application is a continuation of co-pending U.S. application Ser. No. 17/013,504 filed on 4 Sep. 2020 titled “Substrate-Mountable Electromagnetic Waveguide” from which benefits are claimed under 35 U.S.C. § 120.
Number | Name | Date | Kind |
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6020800 | Arakawa | Feb 2000 | A |
11239539 | Burdick | Feb 2022 | B1 |
Number | Date | Country | |
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20220123451 A1 | Apr 2022 | US |
Number | Date | Country | |
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Parent | 17013504 | Sep 2020 | US |
Child | 17567122 | US |