Integrated filter-coupler for RF signals

Abstract

An integrated filter-coupler includes a body, with the body including a first through passage including a first filter structure, a second through passage substantially parallel to the first through passage and including a second filter structure, and a first dielectric structure disposed between the first filter structure and the second filter structure and that enables signal coupling.

Description

INTEGRATED FILTER-COUPLER FOR RF SIGNALSFIELD

[0001] The present disclosure is generally directed to integrated filter-couplers, such as for use in radio frequency (RF) applications.BACKGROUND

[0002] Couplers and filters are useful for RF applications, such as massive Multi- Input MultiOutput (mMIMO) radios, and can be realized with various structures such as microstrips, striplines, and waveguides. In related art mMIMO radio Antenna Filter Unit (AFU) calibration solutions that include a signal coupler and signal filter, the coupler is located after the filter, and in some cases, on a separate printed circuit board (PCB).BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Fig. 1 illustrates a block diagram of a system that includes an integrated filter-coupler according to at least one embodiment.

[0004] Figs. 2A-2C illustrate various views of an integrated filter-coupler according to at least one embodiment.

[0005] Figs. 3A and 3B depict two circuit equivalents of an integrated filter-coupler according to at least one embodiment.

[0006] Figs. 4A and 4B illustrate various signal parameters achieved with an integrated filtercoupler according to at least one embodiment.

[0007] Figs. 5A and 5B illustrate various views of another example of an integrated filtercoupler according to at least one embodiment.

[0008] In the appended figures, similar components and / or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a letter that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.DETAIEED DESCRIPTION

[0009] Embodiments of the present disclosure relate to integrated filter-couplers for RF applications. In related art solutions, the coupler and filter(s) are typically separate devices, leading to increased footprint, power consumption, and cost associated therewith. Integrating filtering and coupling functions into a single device according to embodiments of the present disclosure, however, may reduce component size and cost (e.g., reduce mMIMO radio size and cost due to lower AFU RF transmission losses). Embodiments of the present disclosure may also reduce radio power consumption, thermal load, and network operating costs. Integrated filtercouplers according to the present disclosure may exhibit improved accuracy and isolation against unwanted noise and disturbances, which is especially important in mMIMO radio calibration and over-the-air (OTA) beamforming applications. In the context of mMIMO, an integrated filtercoupler may enable lower cost mMIMO calibration PCBs since the wanted transmit and receive RF signals are not routed via a calibration PCB, or allow shorter line lengths to be used on the lossy calibration PCB substrate. Embodiments of the present disclosure further enable accurate module or even system level filter testing, tuning and monitoring, which may be used as accurate hardware calibration data for radio calibration software algorithm. Embodiments of the present disclosure are also well suited for RF “connectorless” interfaces, thereby minimizing radio unit RF connector costs. Example embodiments provide an integrated lowpass filter and coupler, which are needed in mMIMO applications, in such a way that solution is both compact and low loss.

[0010] Integrated filter-couplers according to embodiments enable the low loss and accurate mMIMO AFU calibration coupler interface using, for example, a fixed dual coaxial low pass filter (EPF)-coupler integrated structure described herein. In this example, two separate AFU functions are combined to reduce the required length and insertion loss of the traditional cascaded discrete EPF and coupler solutions.

[0011] The combined EPF and coupler characteristics can be easily tuned together for optimized performance. Other applications include RF test solutions such as simultaneous time aligned multiport measurements (e.g., in mMIMO production calibration). In some examples, the number of ports of an integrated filter-coupler is increased with a symmetrical cylinder, “revolver,” construction having a measurement branch in the center of the revolver structure. The symmetrical structure may enable improved ways of mMIMO calibration. Said “revolver”design could be used e.g. in 5G over-the-air (OTA) test systems for accurate multipath amplitude and phase balanced RF measurements and as a signal combiner / divider. The LPFs forming the coupler do not need to be the same order and can be optimized for the application.

[0012] Fig. 1 illustrates a block diagram of a system 100 that includes an integrated filtercoupler 104, also called a “filter-coupler,” which may be free-floating or mounted on or integrated with a substrate, such as a PCB (not shown). Figs. 2A-2C illustrate various views of the filter-coupler 104 from Fig. 1 while Figs. 3A and 3B depict two circuit equivalents of the filter-coupler 104. Still further, Fig. 4A illustrates a graph showing insertion loss and Fig. 4B illustrates various other signal parameters for an example filter-coupler 104. The filter-coupler 104 is integrated in that both signal filtering and signal coupling functions are achieved within the same compact device. Although not explicitly shown, it should be appreciated that the system 100 may include additional elements, such as components related to the application for which the filter-coupler 104 is being used (e.g., signal generation circuits, antenna components for signal transmission / reception, and / or the like). Example embodiments are described in more detail below with reference to Figs. 1 to 4B.

[0013] As shown in Fig. 1, the filter-coupler 104 comprises ports Pl to P4, filter structures 116a and 116b, and a coupling area 124 positioned between the filter structures 116a and 116b. Fig. 1 shows a non-limiting example where port Pl is an input port that receives an input signal, port P2 is an output port that outputs a filtered version of the input signal (e.g., outputs a lowpass filtered signal to an antenna), port P3 is a coupled port that outputs a coupled signal via coupling area 124, and port P4 is an isolated port that is terminated (e.g., port P4 is terminated internally or externally to a 50 ohm impedance). However, example embodiments are not limited to this arrangement, and the functions of each port may change depending on signal flow and application. For example, port P2 may be the input port, port Pl the output port, port P4 the coupled port, and port P3 the isolated port. In any event, ports Pl and P2 are electrically isolated from ports P3 and P4. Although not explicitly shown, each port P may comprise and / or be connected to a corresponding connector (e.g., a coaxial connector) that connects to another element of the system 100 (e.g., a signal generator that generates the input signal, an antenna that transmits the output signal, computer processing circuitry that processes the coupled signal after analog to digital conversion, and / or the like).

[0014] The filter structures 116 filter RF signals by passing frequencies within a desired frequency range. The coupling area 124 couples the signal input to a first port P (for output from a second port P) to a third port P that is isolated from the first and second ports. In the example of Fig. 1, the coupling area 124 couples the signal input port Pl to port P3 so that port P3 outputs a coupled signal. In general and as discussed in detail below, the coupling area 124 comprises a dielectric structure or material, such as an air gap or other suitable dielectric, positioned between the filter structures 116a and 116b. In any event, ports Pl and P2 are electrically isolated from or not electrically connected to ports P3 and P4.

[0015] In some examples, the filter structures 116 comprise lowpass filters that pass frequencies suitable for mMIMO applications (e.g., frequencies below 6GHz). In some examples and as described in more detail below, the filter structures 116 may each comprise a filter of an order higher than two, such as a third order filter or a fifth order filter. As discussed in more detail below, the filter structures 116 may each comprise a coaxial structure that passes through the integrated filter-coupler 104 and that has passive components, such as inductive elements and capacitive elements, arranged in each coaxial structure.

[0016] Fig. 2A illustrates a perspective view of a body 200 of an integrated filter-coupler 104 while Figs. 2B and 2C illustrate different cross sectional views of the body 200 to show additional details of the integrated filter-coupler 104. For example, Fig. 2B illustrates a “see through” cross sectional view while Fig. 2C illustrates a true (or truer than Fig. 2B) cross sectional view.

[0017] As illustrated in Figs. 2A to 2C, the body 200 includes a first through passage 208a having a first filter structure 116a, and a second through passage 208b having a second filter structure 116b. The first and second through passages 208a and 208b may be electrically isolated from each other and extend through the body 200 from one side of the body 200 to an opposite side of the body 200. The first and second through passages 208a and 208b may be substantially identical in one or more dimensions. As shown, the second through passage 208b is substantially parallel to the first through passage 208a. In some examples, a plane that is substantially perpendicular to a central axis Al of the first through passage 208a and a central axis A2 of the second through passage 208b intersects both central axes Al and A2. In Fig. 2C, this plane may correspond to the plane along which the cross-section is taken (i.e., a vertical plane that passes through centers of through passages 208a and 208b). Stated another way, the central axes and Aland A2 are substantially aligned with one another in a vertical direction of Fig. 2C. The term “substantially” as used herein is intended account for manufacturing tolerances or other factors that may cause slight variations in a dimension of an element or a relationship between elements.

[0018] Parts of the body 200 other than the filter structures 116a and 116b and the coupling area 124 may comprise a conductive material, such as aluminum or other suitable conductor (e.g., copper). It should be appreciated that Fig. 2C illustrates this feature with shaded regions. Meanwhile, Fig. 2B does not include the shaded regions due to the “see through” view of the elements of the filter-coupler 104. The body 200 may be grounded or serve as ground for the capacitive elements of the filter structures 116a and 116b. In some examples, however, the body 200 may be made of an insulating material, in which case each through passage 208a and 208b may have a conductive coating on inner surfaces thereof to serve as ground. The body 200 may have a cuboid shape or other suitable 3D shape. As shown in Figs. 2B and 2C, the filter structures 116a and 116b may be coaxial in nature in that each includes an insulating material (e.g., air) between two conductors such as a conductor 204 and the part of the conductive body 200 through which a passage 208 extends. The coaxial structures shown and described below are cylindrical, but may take any suitable form, such as rectangular, triangular, and / or the like.

[0019] As may be appreciated, the coaxial structure for a first filter structure 116a comprises a conductor 204a (e.g., a cylindrical conductor) that passes through a dielectric structure 216a while the coaxial structure for a second filter structure 116b comprises a conductor 204b (e.g., a cylindrical conductor) that passes through a dielectric structure 216b. Each conductor 204a and 204b may comprise aluminum, copper, or other suitable coaxial conductive material. In some examples, the body 200 and the conductors 204a and 204b comprise the same material.

[0020] The dielectric structures 216a and 216b may comprise Teflon®, or other suitable low loss dielectric material with sufficient dielectric strength to prevent electrical breakdown. In low RF power applications, the low loss dielectric material may comprise air gap, if filter CLC element concentric positioning is ensured outside filter structures 116a and 116b. Purpose of these dielectrics is to lock the inner conductors 204a and 204b with inductive and capacitive elements concentric to 208a and 208b and provide improved insulation against high electric field strengths between capacitive elements and ground 200. Each dielectric structure 216a and 216b is on an interior surface of a respective through passage 208a and 208b. As may be appreciated, the “see through” view in Fig. 2B illustrates the dielectric structures 216a and 216b as beingtubed shaped while Fig. 2C shows how outer surfaces of the dielectric structures 216a and 216b contact inner surfaces of a respective through passage 208a and 208b. In this non-limiting example, each dielectric structure 216 contacts a through passage 208 around at least part of an inner circumference of the through passage 208 along a length LI of the dielectric structure 216. In some examples, as shown in Fig. 2C, each dielectric structure 216a and 216b includes a section in contact with (or near contact with) a dielectric structure 212 of the coupling area 124, where the dielectric structure 212 corresponds to an air gap between dielectric structures 216a and 216b in Fig. 2C. The “see-through” view in Fig. 2B illustrates a dielectric structure 212 with walls, which may correspond to parts of the body 200 that create a cavity in which the air gap exists. It should be appreciated that the dielectric structure 212 may additionally or alternatively comprise a dielectric material other than air. In some examples, the dielectric constant of structure 212 is less than the dielectric constant of structures 216a and 216b to create the coupling area 124. In an example, material of the dielectric structure 212 is air.

[0021] As shown in Fig. 2C, the length LI of each dielectric structure 216a and 216b may be greater than a length L2 of the dielectric structure 212 so that ends of each dielectric structure 216a and 216b immediately adjacent the dielectric structure 212 contact part of a respective through passage 208. In addition, a length of each conductor 204a and 204b is longer than a length of a corresponding dielectric structure 216a and 216b. As may also be appreciated from these figures, each conductor 204a and 204b and the body 200 may have a substantially same length. Various details of the conductors 204a and 204b are described below, in some cases with reference to a specific conductor 204a or 204b, but the same or similar details should be understood to apply to the other conductor 204 not being specifically referenced.

[0022] With reference to Fig. 2C, the conductor 204a includes a first part 220, a second part 224, and a third part 228 that extends between the first part 220 and the second part 224. The first, second, and third parts of a conductor 204 may be arranged within a corresponding dielectric structure 216. As described in more detail below, these three parts of a conductor 204 in combination with the dielectric materials 212 and 216 form a filter structure, such as a CLC filter circuit shown in Fig. 3A.

[0023] Fig. 2C illustrates various diameters D (also referred to as widths in the event of non- cylindrical shapes) along a length of the conductor 204a, such as a diameter DI of a section of conductor 204a outside of a filter structure, a diameter D2 of the first part 220 of the conductor204a, a diameter D3 of the second part 224 of the conductor 204a, and a diameter D4 of the third part 228 of the conductor 204a. Diameters D2 and D3 may be substantially the same and be wider or greater than the diameter D4. In addition, diameter D4 of the third part 228 may be the same as or less than diameter DI of the conductor 204a. The first part 220 and the second part 224 may contact or nearly contact at least part of the dielectric structure 216a, which has a diameter D5 that is slightly greater than diameters D2 and D3 and slightly less than or practically the same as diameter D6 of passage 208a, so as to form two different capacitive structures separated by an inductive structure that includes the third part 228. The two capacitive structures and the inductive structure form the CLC circuit for the filter structure 116a in Fig. 3 A. As may be appreciated and with reference to filter structure 116a in Figs. 2C and 3 A, a first capacitive structure C (leftmost capacitor C in Fig. 3A) is formed by the portion of the dielectric structure 216a sandwiched between the first part 220 and the body 200 (recalling that the body 200 is a conductive material), and a second capacitive structure C (rightmost capacitor C in Fig. 3A) is formed by the portion of the dielectric structure 216a sandwiched between the second part 224 and the body 200. Meanwhile, an inductive structure L is formed between the two capacitive structures C and includes the third part 228 of conductor 204a acting as the conductive “coil” part of an inductor. The same arrangement is true for the filter structure 116b. In an example, each of the inductive structures comprises a narrowed portion provided on the corresponding conductor, and each of the capacitive structures comprises a broadened portion provided on the corresponding conductor. Herein, a narrowed portion is a portion whose cross-sectional area is smaller than main cross-sectional area of the conductor, and a broadened portion is a portion whose cross-sectional area is greater than main cross-sectional area of the conductor.

[0024] As may be appreciated, Figs. 2A-2C illustrate the structure for implementing the third order CLC filter circuit shown in Fig. 3A. For the sake of completeness, Figs. 3A and 3B illustrate how each port Pl to P4 has an associated impedance Z (e.g., a 50 ohm impedance). Each capacitance C may have a substantially same value and each inductance L may have a substantially same value. In an example, inductance and capacitance values may differ from each other and can be tuned for optimal application specific frequency performance.

[0025] Here, it should be understood that although example embodiments have been shown and described with respect to filter structures having identical or near identical features such as the number of orders and values of components (capacitance and inductance values),embodiments are not limited thereto. For example, each filter structure may be of a different order and comprise capacitor and inductor components having values that differ between filter structures. It should further be appreciated that physical characteristics of the filter-coupler 104, such as the sizes of elements in each filter structure, element spacing, and / or number of filter structures may vary depending on certain factors, such as the intended frequency of an input signal and / or the application in which the filter-coupler 104 is deployed.

[0026] Figs. 4A and 4B illustrate simulated signal parameters for the filter-coupler 104 in Figs. 2A to 2C constructed (e.g., optimized) to receive a 4GHz input signal at port Pl. As shown in Fig. 4A and in curve S2 of Fig. 4B, the insertion loss between input port Pl and output P2 is less than 0.05dB at 4GHz. Meanwhile, curve SI shows the input matching of port Pl is about 40dB at 4GHz, curve S3 shows the coupling between input port Pl and coupled port P3 to be about 40dB, and curve S4 shows the coupling between the input port Pl and the isolated port P4 to be about 52dB.

[0027] Figs. 1 to 4B have been described with reference to an integrated filter-coupler 104 having two filter structures. However, more through passages and filter structures may be included. Figs. 5A and 5B illustrate a perspective view and an end view, respectively, of an integrated filter-coupler 104a having a body 200a including seven substantially parallel through passages 500, with each through passage 500 having two of its own ports and its own filter structure similar to or the same as those described above with reference to Figs. 1 to 4B. It may be said that Figs. 5A and 5B illustrate a revolver structure in which six through passages 208 surround a center through passage. In some examples, ports of the center through passage serve as the coupled and isolated ports for one or more of the remaining ports. In other examples, all surrounding through passages serve as coupled and isolated ports for the center passage. As shown in Fig. 5B, the revolver structure has at least four lines of symmetry Syl, Sy2, Sy3, and Sy4. In some examples, there are no lines of symmetry.

[0028] In view of the above, at least one embodiment of the present disclosure provides an integrated filter-coupler comprising a body 200 that includes a first through passage 208a including a first filter structure 116a, a second through passage 208b substantially parallel to the first through passage 208a and including a second filter structure 116b, a first dielectric structure 212 disposed between the first filter structure 116a and the second filter structure 116b and that enables signal coupling. In some examples, the first filter structure 116a comprises a firstlowpass filter having more than two orders, and the second filter structure 116b comprises a second lowpass filter having more than two orders. In at least one embodiment, the first dielectric structure 212 comprises an air gap in the body 200 between the first filter structure 116a and the second filter structure 116b. The air gap may have a substantially same width as the portion 202 of the body 200 between through passages 208a and 208b, as in Fig. 2C.

[0029] The first filter structure 116a and the second filter structure 116b each comprise a coaxial structure, with the coaxial structure for each of the first filter structure 116a and the second filter structure 116b comprising a second dielectric structure 216, a conductor 204 that passes through the second dielectric structure 216. As shown in the figures, the conductor 204 includes a first part 220, a second part 224, and a third part 228 that extends between the first part 220 and the second part 224. In at least one embodiment, the first part 220 and the second part 224 are wider than the third part 228, and the first part 220 and the second part 224 contact the second dielectric structure 216. At least a portion of the first part 220 and the second part 224 has the same or similar shape as at least part of the through passage 208a. In addition, a length of the conductor 204 is longer than a length of the second dielectric structure 216, and in some cases, the conductor 204 and the body 200 have a substantially same length. In some examples, a length of the second dielectric structure 216 is greater than a length of the first dielectric structure 212. As shown and described, the first dielectric structure 212 is disposed between the second dielectric structure 216a of the first filter structure 116a and the second dielectric structure 216b of the second filter structure 116b. As noted herein, the first dielectric structure 212 comprises an air gap, and the body 200 is conductive so as to form at least part of the capacitances of the filter structures. A plane that is perpendicular to a central axis Al of the first through passage 208a and a central axis A2 of the second through passage 208b intersects both central axes. As shown in Figs. 5A and 5B, the body 200 may further comprise additional through passages 208, with each additional through passage including an additional filter structure. As also shown in Figs. 5A and 5B, the one or more additional through passages may include the second through passage and have a revolver configuration to surround the first through passage. In this case, the body 200 comprises an additional dielectric structure 212 between each of the one or more additional through passages 208 and the first through passage to couple each of the one or more additional through passages to the first through passage.

[0030] In view of the above, at least one embodiment of the present disclosure is directed to an integrated filter-coupler 104 comprising a first port, a second port, a third port, and a fourth port, a first through passage 208a including a first filter structure 116a positioned between the first port and the second port, a second through passage 208b substantially parallel to the first through passage 208a and including a second filter structure 116b positioned between the third port and the fourth port, and a first dielectric structure 212 between the first filter structure 116a and the second filter structure 116b and that enables coupling of a signal input to the first port or the second port to the third port or the fourth port (with the other of the first port or the second port being the output port and the other of the third port or the fourth port being the isolated port). The first filter structure 116a may comprise a first CLC filter, and the second filter structure 116b comprises a second CLC filter.

[0031] In view of the above, at least one embodiment of the present disclosure is directed to an integrated filter-coupler comprising a conductive body including a first through passage 208a including a first lowpass filter, a second through passage 208b substantially parallel to the first through passage and including a second lowpass filter, and an air gap 212 between the first through passage and the second through passage.

[0032] The present disclosure, in various aspects, embodiments, and / or configurations, includes components, methods, processes, systems, and / or apparatus substantially as depicted and described herein, including various aspects, embodiments, configurations embodiments, subcombinations, and / or subsets thereof. Those of skill in the art will understand how to make and use the disclosed aspects, embodiments, and / or configurations after understanding the present disclosure. The present disclosure, in various aspects, embodiments, and / or configurations, includes providing devices and processes in the absence of items not depicted and / or described herein or in various aspects, embodiments, and / or configurations hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and\or reducing cost of implementation.

[0033] The foregoing discussion has been presented for purposes of illustration and description. The foregoing is not intended to limit the disclosure to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the disclosure are grouped together in one or more aspects, embodiments, and / or configurations for the purpose of streamlining the disclosure. The features of the aspects, embodiments, and / or configurations ofthe disclosure may be combined in alternate aspects, embodiments, and / or configurations other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the claims require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed aspect, embodiment, and / or configuration. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the disclosure.

[0034] Moreover, though the description has included description of one or more aspects, embodiments, and / or configurations and certain variations and modifications, other variations, combinations, and modifications are within the scope of the disclosure, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative aspects, embodiments, and / or configurations to the extent permitted, including alternate, interchangeable and / or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and / or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.

[0035] The phrases “at least one”, “one or more”, and “and / or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and / or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as XI -Xn, Yl-Ym, and Zl-Zo, the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (e.g., XI and X2) as well as a combination of elements selected from two or more classes (e.g., Y1 and Zo).

[0036] As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “include,” “including,” “includes,” “comprise,” “comprises,” and / or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.The term “and / or” includes any and all combinations of one or more of the associated listed items.

Claims

CLAIMS1. An integrated filter-coupler, comprising: a body comprising: a first through passage including a first filter structure; a second through passage substantially parallel to the first through passage and including a second filter structure; and a first dielectric structure disposed between the first filter structure and the second filter structure and that enables signal coupling.

2. The integrated filter-coupler of claim 1, wherein the first filter structure comprises a first lowpass filter having more than two orders, and wherein the second filter structure comprises a second lowpass filter having more than two orders.

3. The integrated filter-coupler of claim 1, wherein the first dielectric structure comprises an air gap in the body between the first filter structure and the second filter structure.

4. The integrated filter-coupler of claim 1, wherein the first filter structure and the second filter structure each comprise a coaxial structure.

5. The integrated filter-coupler of claim 4, wherein the coaxial structure for each of the first filter structure and the second filter structure comprises: a second dielectric structure; and a conductor that passes through the second dielectric structure, the conductor including a first part, a second part, and a third part that extends between the first part and the second part.

6. The integrated filter-coupler of claim 5, wherein the first part and the second part are wider than the third part.

7. The integrated filter-coupler of claim 6, wherein the first part and the second part contact the second dielectric structure.

8. The integrated filter-coupler of claim 5, wherein a length of the conductor is longer than a length of the second dielectric structure.

9. The integrated filter-coupler of claim 8, wherein the conductor and the body have a substantially same length.

10. The integrated filter-coupler of claim 5, wherein a length of the second dielectric structure is greater than a length of the first dielectric structure.

11. The integrated filter-coupler of claim 5, wherein the first dielectric structure is disposed between the second dielectric structure of the first filter structure and the second dielectric structure of the second filter structure.

12. The integrated filter-coupler of claim 11, wherein the first dielectric structure comprises an air gap.

13. The integrated filter-coupler of claim 1, wherein the body is conductive.

14. The integrated filter-coupler of claim 1, wherein a plane that is perpendicular to a central axis of the first through passage and a central axis of the second through passage intersects both central axes.

15. The integrated filter-coupler of claim 1, wherein the body further comprises: one or more additional through passages, each additional through passage including an additional filter structure.

16. The integrated filter-coupler of claim 15, wherein the second through passage and the one or more additional through passages have a revolver configuration to surround the first through passage.

17. The integrated filter-coupler of claim 16, wherein body comprises an additional dielectric structure between each of the one or more additional through passages and the first through passage to couple each of the one or more additional through passages to the first through passage.

18. An integrated filter-coupler, comprising: a first port, a second port, a third port, and a fourth port; a first through passage including a first filter structure positioned between the first port and the second port; a second through passage substantially parallel to the first through passage and including a second filter structure positioned between the third port and the fourth port; and a first dielectric structure between the first filter structure and the second filter structure and that enables coupling of a signal input to the first port or the second port to the third port or the fourth port.

19. The integrated filter-coupler of claim 18, wherein the first filter structure comprises a first CLC filter, and wherein the second filter structure comprises a second CLC filter.

20. An integrated filter-coupler, comprising: a conductive body comprising: a first through passage including a first lowpass filter; a second through passage substantially parallel to the first through passage and including a second lowpass filter; and an air gap between the first through passage and the second through passage.

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