Patent Description:
Communications systems utilize various filters to allow or inhibit signals selectively with varying frequency. Typically, noise or unwanted frequencies are inhibited or blocked and the desired signal is allowed to pass through for processing. Some band pass filters are constructed using elements that resonate.

One type of communication system, satellite communication systems, utilize microwave communications frequencies that range from <NUM>-<NUM> Gigahertz (GHz). Additional goals of many satellite-based communication system components are to reduce weight in order to reduce costs associated with launching a satellite into orbit and to utilize approved components for space technology. Developing communication materials that utilize approved materials, have a reduced weight, and provide the correct signal processing characteristics is a challenge.

Patent document <CIT>, in accordance with its abstract, describes a dielectric filter including a shielding cavity frame having electric conductivity, a dielectric having electrodes formed on two opposing faces and disposed in the shielding cavity frame, and external coupling means, wherein the external coupling means includes an electric probe at least a part of which is covered with a covering dielectric.

Patent document <CIT>, in accordance with its abstract, describes at least three resonators, mounted in series in the wave propagation direction between parallel plates, form the microwave filter and are in the form of pins. Their inductive and capacitive coupling is determined by their spacing. At least one bypass coupling is provided between two resonators not immediately adjacent. The bypass coupling is so rated that the asymmetry of the filter pass characteristic is compensated. This asymmetry is produced by inductive coupling between not adjacent resonators. If at least four resonators are used, at least two capacitive additional couplings are provided between not adjacent resonators to make the design symmetric.

Patent document <CIT>, in accordance with its abstract, describes a filter comprising a cavity with an inner cavity, an input end and an output end, wherein the input end and the output end are installed on the cavity, at least two resonant cavities are formed in the cavity, a harmonic oscillator is arranged in each resonant cavity, the input end and the output end of each resonant cavity are of a structure with wires in the middle and insulating material surrounding the wires, every two adjacent cavities are mutually connected through a metal piece electrically , and at least a part of the projection of the metal piece in the direction from the output ends of every two adjacent resonant cavities to the input ends of every two adjacent resonant cavities is located outside the projection of the wires in the same direction, wherein the wires are located at the output ends and the input ends of every two resonant adjacent cavities.

Patent document <CIT>, according to its abstract, states: a filter for radio frequency signals comprises a first cavity resonator, a second cavity resonator, an inner separating plate separating the first cavity resonator and the second cavity resonator and extending upwards from a base plate, a first capacitive coupling means penetrating the inner separating plate at a first height level with respect to the base plate and a second capacitive coupling means penetrating the inner separating plate at a second height level with respect to the base plate.

Patent document <CIT>, according to its abstract, states: a PCB cross coupling piece. The PCB cross coupling piece is applied in a passive cavity and is a PCB provided with a copper sheet layer in the middle. With the adoption of the PCB cross coupling piece, the PCB provided with the copper sheet layer in the middle is adopted to replace a prior art cross coupling rod. The PCB provided is shaped in one-time processing.

Patent document <CIT> discloses a coaxial resonator filter with a cross-couple between adjacent cavities, wherein the cross-couple allows extending the arms carrying the capacitive plates in a symmetric way for providing tuning flexibility.

In one aspect of the present disclosure, a tunable probe includes a first resonator, a second resonator spaced from the first resonator, and a cross-couple extending from the first resonator to the second resonator. The cross-couple includes a first substrate and a second substrate disposed between the first and second resonators to create a capacitance between the first and second resonators. The cross-couple further includes a wire connecting the first and second substrates and a dielectric surrounding the wire.

In another aspect of the invention, a cross-couple for a tunable probe includes a first substrate and a second substrate, the first and second substrates both having a first portion and a second portion. A wire connects the first portion of the first and second substrates and a dielectric surrounds the wire. In one embodiment, the first portion is a metallic portion and the second portion is an alumina substrate portion.

In another aspect of the invention, a method of tuning a tunable probe is provided. In such a method, a cross-couple is disposed between a first resonator and a second resonator. The cross-couple includes a first substrate and a second substrate disposed between the first and second resonators to create a capacitance between the first and second resonators, a wire connecting each of the first and second substrates, and a dielectric surrounding the wire. The method further includes adjusting a position of the cross-couple along a lateral axis between the first and second resonators and bonding the cross-couple in place between the first and second resonators. Additional aspects are defined by the claims of this patent.

<FIG> is an isometric view of a first tunable probe in accordance with an embodiment of the present disclosure. In particular, <FIG> depicts the tunable probe <NUM> that includes a tunable-probe inlet <NUM> and a tunable-probe outlet <NUM> connected to the housing <NUM>. The tunable probe <NUM> may be connected into a communication system via the tunable probe inlet <NUM> and outlet <NUM> in order to provide filtering characteristics to the radio frequency (RF) signals in the communication system. The housing <NUM> includes a gap <NUM> between a first arm <NUM> and a second arm <NUM>. The tunable probe <NUM> may also include various tunable screws <NUM> disposed about the housing between the resonators <NUM>.

The tunable probe <NUM> further includes a plurality of resonators <NUM>. As used throughout the description, the positions of the resonators are indicated by a suffix after the resonator number (e.g., the '<NUM>' in '<NUM>-<NUM>' indicates a sixth resonator position). Thus, in <FIG>, the tunable probe <NUM> includes twelve (<NUM>) resonators <NUM>. A resonator <NUM> may be realized by a cylindrical-shaped cavity within the housing <NUM>. A resonator <NUM> is included at a first resonator position <NUM>-<NUM> within the housing <NUM> adjacent to the tunable-probe inlet <NUM>. In accordance with the numbering convention, the resonator positions increase incrementally in a counter-clockwise direction along the housing <NUM>, starting at the tunable-probe inlet <NUM>. Thus, proceeding in a counter-clockwise direction, the next resonator position after the first resonator position <NUM>-<NUM> is the second resonator position <NUM>-<NUM>. The convention continues through to the twelfth (and final) resonator position <NUM>-<NUM> adjacent to the tunable-probe outlet <NUM>.

In accordance with an embodiment, a tunable probe <NUM> includes a first resonator <NUM> spaced apart from the second resonator <NUM>. For example, the first resonator <NUM> may be at the fourth resonator position <NUM>-<NUM> and the second resonator <NUM> may be at the ninth resonator position <NUM>-<NUM>, which is spaced apart and across from the first resonator <NUM>. A cross-couple <NUM> extends from the first resonator <NUM> to the second resonator <NUM>. The cross-couple <NUM> is discussed in more detail in conjunction with the discussion of <FIG>.

In general, the resonators <NUM> in a tunable probe are grouped in pairs. For example, the tunable probe <NUM> includes six pairs of resonators <NUM>. Each of the six pairs include two resonators <NUM> located opposite of each other. A first pair includes the resonators <NUM> located at the first resonator position <NUM>-<NUM> and the twelfth resonator position <NUM>-<NUM>. The sixth pair includes the resonators <NUM> located at the sixth resonator position <NUM>-<NUM> and the seventh resonator position <NUM>-<NUM>. As discussed later in the description, one method of improving signal processing capabilities of a tunable probe is to increase the number of pairs of resonators <NUM> within the housing <NUM>. However, this method results in excess material in a larger housing. Another method is to include a cross-couple between a pair of resonators, such as the cross-couple <NUM>. At higher frequencies, a conductive wire may be able to provide sufficient capacitance to provide the desired signal processing characteristics. However, at frequencies under <NUM>, the capacitance of a just a conductive wire may not be sufficient to achieve the desired response.

<FIG> is a detailed view of a cross-couple of the first tunable probe depicted in <FIG>, in accordance with an embodiment of the present disclosure. In particular, <FIG> depicts the view <NUM>, which is a top-view of a portion of the tunable probe <NUM> and details aspects of the cross-couple <NUM>. The cross-couple <NUM> includes a first substrate <NUM>-<NUM> in proximity to the first resonator <NUM> located at resonator position <NUM>-<NUM> and a second substrate <NUM>-<NUM> in proximity to the second resonator <NUM> located at resonator position <NUM>-<NUM>. The cross-couple <NUM> is disposed between the first and second resonators <NUM> to create a capacitance between the first and second resonators <NUM>. A wire <NUM> connects the first and second substrates <NUM>-<NUM>, <NUM>-<NUM>. A dielectric <NUM> surrounds the wire <NUM>. In some embodiments, the wire <NUM> is a silver wire, although certainly other conductive materials such as copper, gold, or the like may be used. The dielectric <NUM> also prevents the wire <NUM> from shorting against the housing <NUM>.

In some embodiments, the first and second resonators <NUM> are disposed in the housing <NUM>. A space between the first arm <NUM> and the second arm <NUM> defines a gap <NUM>. The wire <NUM> extends across the gap <NUM> to define an exposed wire portion, and the dielectric <NUM> surrounds the exposed wire portion.

In some embodiments, the tunable probe <NUM> is configured to operate in either one or both of the X and L microwave communication/radio/frequency bands having a frequency range between <NUM>-<NUM> and <NUM>-<NUM>, respectively. At such frequency ranges, the capacitance of a conductive wire alone utilized as a cross-couple between a pair of resonators <NUM> is insufficient to create the desired filtering performance of the tunable probe. In order to provide sufficient capacitance, the cross-couple <NUM>, extending between two resonators <NUM>, includes a first substrate <NUM>-<NUM> and a second substrate <NUM>-<NUM> connected via the wire <NUM>. The first substrate <NUM>-<NUM> is located in proximity to the first resonator <NUM> at the fourth resonator position <NUM>-<NUM> and the second substrate <NUM>-<NUM> is located in proximity to the second resonator <NUM> at the ninth resonator position <NUM>-<NUM>. In some such embodiments, the material of the first and second substrates <NUM>-<NUM>, <NUM>-<NUM> are selected to have a material permittivity (εr and also illustrated as Er) between <NUM> and <NUM>. One such material may include alumina substrate.

As further detailed in <FIG>, the first substrate <NUM>-<NUM> and the second substrate <NUM>-<NUM> may both include a first portion <NUM>-<NUM> and <NUM>-<NUM>, respectively, and a second portion <NUM>-<NUM> and <NUM>-<NUM>, respectively. The wire <NUM> connects the first portion <NUM>-<NUM> of the first substrate <NUM>-<NUM> with the first portion <NUM>-<NUM> of the second substrate <NUM>-<NUM>. In some embodiments, the second portion (<NUM>-<NUM>, <NUM>-<NUM>) is oriented towards a respective resonator (<NUM>, <NUM>) comprising the first resonator or the second resonator. As such, the second portion <NUM>-<NUM> of the first substrate <NUM>-<NUM> is oriented towards (e.g., is located adjacent to or facing) the first resonator <NUM> on a side opposite of the first portion <NUM>-<NUM> as the wire <NUM>. Similarly, the second portion <NUM>-<NUM> of the second substrate <NUM>-<NUM> is oriented towards (e.g., is located adjacent to) the second resonator <NUM> on a side opposite of the first portion <NUM>-<NUM> as the wire <NUM>. In various embodiments, the material of the first portion <NUM>-<NUM>, <NUM>-<NUM> is metallic (e.g., silver, gold) and the material of the second portion <NUM>-<NUM>, <NUM>-<NUM> is selected based on a desired material permittivity (e.g., alumina substrate).

The first portion <NUM>-<NUM>, <NUM>-<NUM> of the first and second substrates <NUM>-<NUM>, <NUM>-<NUM> may be rectangular and have a length and a width dimension. Further, the second portion <NUM>-<NUM>, <NUM>-<NUM> of the first and second substrates <NUM>-<NUM>, <NUM>-<NUM> may also be rectangular and have a length and a width dimension the same as the first portion <NUM>-<NUM>, <NUM>-<NUM>. The size (e.g., the cross-sectional area) of the first portion <NUM>-<NUM>, <NUM>-<NUM> and the second portion <NUM>-<NUM>, <NUM>-<NUM> may be selected based on desired filtering parameters of the tunable probe <NUM>. In addition to rectangles, the sizes of the first portion <NUM>-<NUM>, <NUM>-<NUM> and the second portion <NUM>-<NUM>, <NUM>-<NUM> may be also be circular, oval, or the like.

In constructing the first and second substrates <NUM>-<NUM>, <NUM>-<NUM>, an inner surface of the first portion <NUM>-<NUM>, <NUM>-<NUM> is affixed to the wire <NUM>. Example methods of affixing to the first portions to the wire <NUM> include bonding with epoxy, soldering, and the like. An outer surface, opposite the inner surface, of the first portion <NUM>-<NUM>, <NUM>-<NUM> is affixed to the second portion <NUM>-<NUM>, <NUM>-<NUM>. Example methods of affixing the first portions to the second portions include bonding with epoxy, folding edges of the first portion <NUM>-<NUM>, <NUM>-<NUM> about the second portion to partially enclose and mechanically capture the second portion <NUM>-<NUM>, <NUM>-<NUM>, and the like. In some embodiments, the substrates <NUM>-<NUM>, <NUM>-<NUM> include the second portion <NUM>-<NUM>, <NUM>-<NUM> affixed directly to the wire <NUM> without the first portion <NUM>-<NUM>, <NUM>-<NUM>.

The tunable probe <NUM> is tunable at least in part by adjusting a location of the dielectric <NUM> along a lateral axis <NUM>. The lateral axis <NUM> extends between the first and second resonators <NUM> and is parallel to a longitudinal axis of the wire <NUM>. The dielectric <NUM> is fixed (e.g., bonded with epoxy) to the wire <NUM> at the determined, based on the desired tuning, location along the lateral axis <NUM> between the first and second resonators <NUM>.

The housing <NUM> may further include a recess in each arm <NUM>, <NUM> along the lateral axis <NUM>. The recesses are configured to receive a portion of the dielectric <NUM> to permit translation of the dielectric <NUM> along the lateral axis <NUM> to assist in tuning of the tunable probe <NUM>. In addition to bonding the dielectric <NUM> to the wire <NUM>, a portion of the dielectric <NUM> may also be bonded to the housing <NUM> at the recesses.

<FIG> is an isometric view of a second tunable probe in accordance with an embodiment of the present disclosure. In particular, <FIG> depicts an isometric view of the tunable probe <NUM>. The tunable probe <NUM> is similar to the tunable probe <NUM> discussed in conjunction with <FIG>. While the tunable probe <NUM> comprises a total of twelve resonators <NUM>, with the cross-couple <NUM> extending between the resonators at the fourth resonator position <NUM>-<NUM> and the ninth resonator position <NUM>-<NUM>, other configurations are likewise achievable. For example, the tunable probe <NUM> includes eight resonators, with a cross-couple extending between the resonators at the second and seventh positions.

The components of the tunable probe <NUM> are similar to like-numbered components of the tunable probe <NUM>, with the tunable probe <NUM> including a tunable-probe inlet <NUM>, a tunable probe outlet <NUM>, a plurality of resonators <NUM>, and a housing <NUM> having a first arm <NUM> and a second arm <NUM>. The first and second arms <NUM>, <NUM> define a gap <NUM>. A cross-couple <NUM> is disposed between the first resonator <NUM> and a second resonator <NUM>. As compared to the tunable probe <NUM>, a first difference is that the tunable probe <NUM> includes <NUM> resonators <NUM> (as compared to <NUM> resonators <NUM> of the tunable probe <NUM>). A second difference is that the cross-couple <NUM> extends between the first resonator <NUM> located at the second resonator position <NUM>-<NUM> and the second resonator <NUM> located at the seventh resonator position <NUM>-<NUM> (as compared to the cross-couple <NUM> extending between resonators <NUM> at the fourth and ninth resonator positions of the tunable probe <NUM>).

<FIG> is a chart of signal processing characteristics of a tunable probe, in accordance with an embodiment of the present disclosure. In particular, <FIG> is a chart <NUM> that depicts the filtering characteristics of the tunable probe <NUM>. In the chart <NUM>, the vertical axis depicts signal level, measured in decibels (dB). The horizontal axis depicts frequency of the communications signal, measured in GHz. The curve <NUM> depicts forward transmission and the curve <NUM> depicts forward reflection, as measured across the tunable-probe inlet <NUM> and the tunable-probe outlet <NUM> at each of the different frequencies.

As exemplified by the forward transmission curve <NUM>, the tunable probe <NUM> acts as a band-pass filter centered around approximately <NUM>. This is indicated by the band pass region <NUM> having a <NUM> dB measurement between <NUM> and <NUM>. A first notch <NUM> is located at a frequency just below the band pass region <NUM> (e.g., <NUM>). A second notch <NUM> is located at a frequency just above the band pass region <NUM> (e.g., <NUM>). Outside of the band pass region <NUM>, the value of the forward transmission curve <NUM> drops off steeply. This occurs at frequencies at and below the first notch <NUM> (e.g., <NUM>) and at frequencies at and above the second notch <NUM> (e.g., <NUM>). The placement of the cross-couple <NUM> extending between the first and second resonators causes the notches <NUM>, <NUM> in the forward transmission curve <NUM>. The steepness (e.g., slope of forward transmission curve <NUM>) of the notches <NUM>, <NUM> is determined at least in part on the lateral position of the dielectric <NUM> along the lateral axis <NUM> and the sizes of the substrates <NUM>-<NUM>, <NUM>-<NUM>. <FIG> depicts a cross-couple, in accordance with an embodiment of the present disclosure. In particular, <FIG> depicts the cross-couple <NUM>, that may be similar to, and used in the place of, the cross-couples <NUM> and <NUM> disclosed herein. The cross-couple <NUM> includes the first and second substrates <NUM>-<NUM>, <NUM>-<NUM>, the dielectric <NUM>, and a wire <NUM>. The first and second substrates <NUM>-<NUM>, <NUM>-<NUM> each include the first portions <NUM>-<NUM>, <NUM>-<NUM> that are near the wire <NUM> and the second portions <NUM>-<NUM>, <NUM>-<NUM> that are opposite of the first portions <NUM>-<NUM>, <NUM>-<NUM> and are configured to be oriented towards a resonator (e.g., <NUM>, <NUM>). The wire <NUM> is similar to the wire <NUM> and further includes bends <NUM>-<NUM>, <NUM>-<NUM> and attachment portions <NUM>-<NUM>, <NUM>-<NUM> on each end of the wire <NUM>. To assemble the cross-couple <NUM>, an initially straight and unbent piece of wire is inserted through a bore hole of the dielectric <NUM>. A forming tool is used to bend the wire to introduce the bends <NUM>-<NUM>, <NUM>-<NUM> and attachment portions <NUM>-<NUM>, <NUM>-<NUM> into the initially straight and unbent piece of wire. Alternatively, the wire may initially include one bend <NUM> and one attachment portion <NUM> on a first end of the wire, with the second end of the wire being straight and unbent. After the second end of the wire is inserted through a bore in the dielectric <NUM>, the second end of the wire may be bent to introduce the second bend <NUM> and the second attachment portion <NUM>.

The first and second substrates <NUM>-<NUM>, <NUM>-<NUM> are attached to the respective attachment portions <NUM>-<NUM>, <NUM>-<NUM> on the respective ends of the wire <NUM>. The attachment portions <NUM>-<NUM>, <NUM>-<NUM> are essentially perpendicular to the first and second substrates <NUM>-<NUM>, <NUM>-<NUM> and provide an increased surface area to attach the substrates <NUM>-<NUM>, <NUM>-<NUM> to the wire <NUM>. Example methods to attach the wire <NUM> to the substrates <NUM>-<NUM>, <NUM>-<NUM> at the attachment portions <NUM>-<NUM>, <NUM>-<NUM> include soldering and gold-epoxying the pieces together at a mating surface <NUM>-<NUM>, <NUM>-<NUM>.

As part of tuning the probe (e.g., <NUM>), the cross-couple <NUM> may be inserted into the housing (e.g., <NUM>) along a lateral axis between a pair of resonators (e.g., along the lateral axis <NUM>). The wire <NUM> is bonded to the dielectric <NUM> at the determined location to tune the probe (e.g., adjust the slope of the notches at either end of the band-pass region).

The teachings of the present disclosure have wide uses throughout industry. In one non-limiting example, the tunable probe <NUM> is utilized in a satellite-based communication system as a band-pass filter, operating in either one of the X and L bands. In such an example, one engineering objective is to manufacture the tunable probe out of materials approved for use in satellite communication systems. Another engineering objective is to reduce the overall weight and size of the tunable probe. A final engineering objective is to have the tunable probe permit communication frequencies of approximately X or L frequency band to pass through while attenuating frequencies outside of a band pass region.

While the tunable probe <NUM> is used in the following example, any other suitable tunable probe (e.g., the tunable probe <NUM>, a tunable probe with a different number of resonators or different location of the cross-couple) may be used.

The tunable probe <NUM> includes components manufactured from an approved list of materials. For example, the wire <NUM> is manufactured from silver, and the second portions <NUM>-<NUM>, <NUM>-<NUM> of the respective substrates <NUM>-<NUM>, <NUM>-<NUM> are manufactured from alumina substrate. The cross-couple <NUM> extends between the first resonator <NUM> located in the fourth resonator position <NUM>-<NUM> and the second resonator <NUM> located in the ninth resonator position <NUM>-<NUM>. The alumina substrate in the cross-couple <NUM> provides sufficient capacitance between the first and second resonators <NUM> in order to provide the appropriate notches <NUM>, <NUM> at either end of the band pass region <NUM>. The tunable probe <NUM> is further able to be tuned, as described in conjunction with <FIG>.

<FIG> is a method of tuning a tunable probe, in accordance with an embodiment of the present disclosure. In particular, <FIG> depicts the method <NUM> that includes disposing a cross-couple between resonators at block <NUM>, adjusting the position of the cross-couple along the lateral axis at block <NUM>, and bonding the cross-couple in place at block <NUM>.

By way of example, the tunable probe <NUM> may be used in order to perform the method <NUM>, although any of the other tunable probes and cross-couples disclosed herein may similarly be used to perform the method <NUM>. In such an example at block <NUM>, the cross-couple <NUM> is disposed between the first and second resonators <NUM>, such as between the resonators at the fourth <NUM>-<NUM> and ninth <NUM>-<NUM> resonator positions. The cross-couple <NUM> may be any cross-couple described herein, and includes a first and a second substrate <NUM>-<NUM>, <NUM>-<NUM> connected by a wire <NUM>, with a dielectric <NUM> surrounding the wire <NUM>.

At block <NUM>, a position of the cross-couple <NUM> is adjusted along the lateral axis <NUM> between the first and second resonators <NUM>. At block <NUM>, the cross-couple <NUM> is bonded in place, at the adjusted position, between the first and second resonators <NUM>.

The scope of protection is determined by the appended claims. Further, the disclosure comprises the following illustrative examples:
In a first example, a tunable probe comprises: a first resonator; a second resonator spaced from the first resonator; and a cross-couple extending from the first resonator to the second resonator, the cross-couple comprising: a first substrate and a second substrate, the first and second substrates disposed between the first and second resonators to create a capacitance between the first and second resonators; a wire connecting the first and second substrates; and a dielectric surrounding the wire.

Optionally, in the tunable probe of the first example, a material permittivity (Er) of the first and second substrates is between <NUM> and <NUM>.

Optionally, in the tunable probe of the first example, the first and second substrates comprise alumina substrate.

Optionally, in the tunable probe of the first example, the tunable probe is configured to operate in either one or both of the X and L frequency bands.

Optionally, in the tunable probe of the first example, the tunable probe is a band pass filter configured to pass a frequency of <NUM>.

Optionally, in the tunable probe of the first example, the first and second substrates comprise both a metallic portion bonded to the wire and an alumina substrate portion facing a respective resonator comprising the first resonator or the second resonator.

Optionally, in the tunable probe of the first example: the first and second resonators are disposed in a housing defining a gap; the wire extends across the gap to define an exposed wire portion; and the dielectric surrounds the exposed wire portion.

Optionally, in the tunable probe of the first example, the wire comprises a silver wire.

Optionally, in the tunable probe of the first example, the tunable probe is tunable at least in part by adjusting a location of the dielectric along a lateral axis and bonding the dielectric to the wire between the first and second resonators.

Optionally, in the tunable probe of the first example, the tunable probe is tuned at least in part by selecting a size of the first and second substrates.

Optionally, in the tunable probe of the first example: the tunable probe comprises twelve resonators; the first resonator is at a fourth resonator position; and the second resonator is at a ninth resonator position, opposite of the fourth resonator position.

Optionally, in the tunable probe of the first example; the tunable probe comprises eight resonators; the first resonator is at a second resonator position; and the second resonator is at a seventh resonator position, opposite of the second resonator position.

In a second example, a cross-couple for a tunable probe is provided, the cross-couple comprising: a first substrate and a second substrate, the first and second substrates having both a first portion and a second portion; a wire connecting the first portion of the first and second substrates; and a dielectric surrounding the wire.

Optionally, in the cross-couple of the second example, the cross-couple is configured to be disposed between a first and second resonator to create a capacitance between the first and second resonators.

Optionally, in the cross-couple of the second example, the cross-couple is configured to tune the tunable probe at least in part by positioning the cross-couple along a lateral axis between the first and second resonators.

Optionally, in the cross-couple of the second example, the first and second substrates comprise alumina substrate having a material permittivity (Er) between <NUM> and <NUM>.

Optionally, in the cross-couple of the second example, the second portion is oriented towards a respective resonator comprising the first resonator or the second resonator.

Optionally, in the cross-couple of the second example, the first and second substrates are bonded to the wire with epoxy.

Optionally, in the cross-couple of the second example, the dielectric is bonded to the wire with epoxy.

In a third example, a method of tuning a tunable probe is provided, the method comprising: disposing a cross-couple between a first resonator and a second resonator, the cross-couple comprising: a first substrate and a second substrate, the first and second substrates disposed between the first and second resonators to create a capacitance between the first and second resonators; a wire connecting each of the first and second substrates; and a dielectric surrounding the wire; adjusting a position of the cross-couple along a lateral axis between the first and second resonators; and bonding the cross-couple in place between the first and second resonators.

While the preceding text sets forth a detailed description of numerous different embodiments, it should be understood that the legal scope of protection is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims defining the scope of protection.

Claim 1:
A tunable probe (<NUM>, <NUM>) comprising:
a first resonator (<NUM>, <NUM>);
a second resonator (<NUM>, <NUM>) spaced from the first resonator (<NUM>, <NUM>); and
a cross-couple (<NUM>, <NUM>) extending from the first resonator (<NUM>, <NUM>) to the second resonator (<NUM>, <NUM>), the cross-couple (<NUM>, <NUM>) comprising:
a first substrate (<NUM>-<NUM>) and a second substrate (<NUM>-<NUM>), the first and second substrates (<NUM>-<NUM>, <NUM>-<NUM>) disposed between the first and second resonators (<NUM>, <NUM>) to create a capacitance between the first and second resonators (<NUM>, <NUM>);
a wire (<NUM>) connecting the first and second substrates (<NUM>-<NUM>, <NUM>-<NUM>); and
a dielectric (<NUM>) surrounding the wire (<NUM>),
wherein the tunable probe (<NUM>, <NUM>) is tunable at least in part by being configured for adjusting a location of the dielectric (<NUM>) along a lateral axis (<NUM>), parallel to a longitudinal axis of the wire (<NUM>), and bonding the dielectric (<NUM>) to the wire (<NUM>) between the first and second resonators (<NUM>).