Patent Grant
8324990
The present invention relates to the field of passive microwave components, and more specifically to waveguide assemblies that comprise a first portion and a second portion that each defines a portion of multiple microwave components therein.
Passive waveguide assemblies are known in the art for handling microwave signals. Such waveguide assemblies generally include multiple waveguide components, such as harmonic filters, circulators, isolators, transmit filters, coupling devices (power monitors) and arc guides, that are all connected together. Each of the waveguide components that is assembled to form the overall waveguide assembly is designed and manufactured as a separate physical component, such that in use, each component is coupled to an adjacent component in order to form the complete waveguide assembly.
In order to enable the waveguide components to be coupled together, each of the components is designed with flanges or connecting interfaces on either end. The flanges/interfaces of two consecutive components are then connected together via bolts or screws, so as to secure two consecutive waveguide components together. Unfortunately, a deficiency with connecting the components of a waveguide output assembly together is that the connection via the flanges results in a certain amount of RF leakage and increases the overall insertion loss of the assembly. RF leakage can cause undesirable interference with the signals being output from the waveguide assembly.
In addition, it is difficult to be able to predict how the individually connected waveguide components will interact with each other once they are all connected together to form the waveguide assembly. More specifically, once the individual waveguide components have been connected together, the performance characteristics of the overall waveguide assembly cannot be predicted with any accuracy. As a result, significant tuning is often required, using either dent tuning or tuning screws, once the waveguide components have been connected together.
In light of the above, there is a need in the industry for an improved waveguide output assembly that alleviates, at least in part, the deficiencies of existing waveguide output assemblies.
In accordance with a first broad aspect, the present invention provides a waveguide assembly comprising a first waveguide portion and a second waveguide portion. The first waveguide portion comprises an interior surface and an exterior surface. The interior surface defines a first portion of a first waveguide component and a first portion of a second waveguide component. The second waveguide portion comprises an interior surface and an exterior surface. The interior surface defines a second portion of the first waveguide component and a second portion of the second waveguide component. The first waveguide portion and the second waveguide portion are adapted for being coupled together to form the waveguide assembly such that, when coupled together, the waveguide assembly comprises at least the first waveguide component and the second waveguide component.
In accordance with a second broad aspect, the present invention provides a method that comprises manufacturing a first waveguide portion of a waveguide assembly, manufacturing a second waveguide portion of the waveguide assembly and coupling the first waveguide portion and the second waveguide portion together. The first waveguide portion comprises an exterior surface, and an interior surface that defines a first portion of a first waveguide component and a first portion of a second waveguide component. The second waveguide portion of the waveguide assembly comprises an exterior surface, and an interior surface that defines a second portion of the first waveguide component and a second portion of the second waveguide component. When the first waveguide portion and the second waveguide portion are coupled together, the interior surface of the first waveguide portion and the interior surface of the second waveguide portion together define the first waveguide component and the second waveguide component.
In accordance with a third broad aspect, the present invention provides a waveguide assembly that comprises a first waveguide portion and a second waveguide portion. The first waveguide portion defines a first portion of a first microwave component and a first portion of a second microwave component. The second waveguide portion defines a second portion of the first microwave component and a second portion of the second microwave component. The waveguide assembly further comprises a matching network defining a space between the first waveguide component and the second waveguide component.
In accordance with a third broad aspect, the present invention provides a method that comprises selecting a desired performance characteristic for a waveguide assembly. The waveguide assembly comprises a first waveguide component and a second waveguide component. The method further comprises determining, at least in part on the basis of the desired performance characteristic for the waveguide assembly, the dimensions of a matching network positioned between the first waveguide component and the second waveguide component.
In the accompanying drawings:
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
The following specification will describe waveguide assemblies in accordance with the present invention with reference to three different examples of implementation; namely waveguide assembly 10 shown in
As will be described in more detail below, each of the waveguide assemblies 10, 40 and 80 comprises a first portion and a second portion, wherein each of the first portion and the second portion defines a portion of multiple waveguide components. As such, when the first portion and the second portion are connected together, the complete waveguide assembly comprises the combination of at least two waveguide components that are integrated into a waveguide assembly made up of only two portions. Although only three examples of implementation are shown and described in the present specification and drawings, it should be appreciated that waveguide assemblies in accordance with the present invention can take on an infinite number of shapes and configurations.
Waveguide Assembly 10—First Non-Limiting Embodiment
Shown in
With reference to
The first waveguide portion 12 and the second waveguide portion 14 of the waveguide assembly 10 will now be described in more detail. As shown in
As shown in
The interior surface 26 of the waveguide portion 12 defines the first portions 16a, 18a, 20a and 22a of the waveguide components 16, 18, 20 and 22. Likewise the interior surface 30 of the waveguide portion 14 defines the second portions 16b, 18b, 20b and 22b of the waveguide components 16, 18, 20 and 22. More specifically, the interior surfaces 26 and 30 each define a portion of the inside shape of the waveguide components 16, 18, 20 and 22. It is the inside shape of each waveguide component that gives the waveguide component its functionality.
When the first waveguide portion 12 and the second waveguide portion 14 of the waveguide assembly are coupled together, the first portions 16a, 18a, 20a and 22a of the waveguide components align with second portions 16b, 18b, 20b and 22b of the waveguide components. As such, the combination of the interior surface 26 of the first waveguide portion 12 and the interior surface 30 of the second waveguide portion 14 together define the complete inside shapes of the waveguide components 16, 18, 20 and 22. It should be appreciated that the inside shapes of these waveguide components can vary greatly. Shown in
In accordance with the present invention, the first portions 16a, 18a, 20a and 22a of the waveguide components can form approximately half of the inside shape of the waveguide components. Alternatively, they can form any percentage thereof. For example, the first portions 16a, 18a, 20a and 22a can define anywhere from 5% to 95% of the inside shape of each of the waveguide components. Likewise, the second portions 16b, 18b, 20b and 22b can also define anywhere from 5% to 95% of the inside shape of each of the waveguide components. It should, however, be appreciated that although the percentage of the inside shape defined by each of the first waveguide portion 12 and second waveguide portion 14 can vary, the first portions 16a, 18a, 20a and 22a and the second portions 16b, 18b, 20b and 22b together define 100% of the inside shape of each of the waveguide components.
As shown in
In an alternative embodiment, the first waveguide portion 12 and the second portion 14 can be fastened together in a permanent manner, wherein the two mating rims 36a and 36b are joined together via welding, for example. In such an embodiment, the first waveguide portion 12 and the second waveguide portion 14 cannot be separated without causing damage to the two portions 12 and 14.
Referring back to
Referring back to
As described above, waveguide assembly 10 incorporates multiple waveguide components (namely components 16, 18, 20 and 22) into a single waveguide assembly 10 that is formed of two waveguide portions.
Waveguide Assembly 40—Second Non-Limiting Embodiment
Shown in
As shown in
The first waveguide portion 42 and the second waveguide portion 44 of the waveguide assembly 40 will now be described in more detail. As shown in
As shown in
When the first portion 42 and the second portion 44 of the waveguide assembly are coupled together, the first portions 52a, 54a, 56a of the waveguide components align with second portions 52a, 54b 56b of the waveguide components. As such, the combination of the interior surface 64 of the first portion 12 and the interior surface 68 of the second portion 14 together define the complete inside shape of the waveguide components 52, 54 and 56. The inside shape of these waveguide components can vary greatly depending on the specific implementation of the waveguide component. Shown in
In accordance with the present invention, the first portions 52a, 54a and 56a of the waveguide components can form approximately half of the inside shape of the waveguide components. Alternatively, they can form any percentage thereof. For example, the first portions 52a, 54a and 56a can define anywhere from 5% to 95% of the inside shape of the waveguide components. Likewise, the second portions 52b, 54b and 56b can also define anywhere from 5% to 95% of the inside shape of the waveguide components. It should, however, be appreciated that although the percentage of the inside shape defined by each of the first portion and second portion can vary, the first portions 52a, 54a and 56a and the second portions 52b, 54b and 56b of the waveguide components together define 100% of the inside shape of the waveguide components.
As shown in
In an alternative embodiment, the first portion 42 and the second portion 44 can be fastened together in a permanent manner, wherein the two mating rims 60a and 60b are joined together via welding, for example. In such an embodiment, the first portion 42 and the second portion 44 are joined such that they cannot be separated without causing damage to the two portions 42 and 44.
Referring back to
Referring back to
In addition, and as best shown in
As described above, waveguide assembly 40 incorporates multiple waveguide components (namely components 52, 54 and 56) into a single waveguide assembly 40 that is formed of two waveguide portions 42 and 44.
Waveguide Assembly 80—Third Non-Limiting Embodiment
Shown in
As shown in
The first waveguide portion 82 and the second waveguide portion 84 of the waveguide assembly 80 will now be described in more detail. As shown in
As shown in
When the first portion 82 and the second portion 84 of the waveguide assembly 80 are coupled together, the first portions 92a, 94a, 96a of the waveguide components align with second portions 92b, 94b 96b of the waveguide components. As such, the combination of the interior surface 102 of the first portion 82 and the interior surface 106 of the second portion 84 together define the shapes of the complete waveguide components; namely the isolator, the harmonic filter and the transmit filter. The shape of these waveguide components can vary greatly depending on the specific implementation of the waveguide component. Shown in
In accordance with the present invention, the first portions 92a, 94a and 96a of the waveguide components can form approximately half of the inside shapes of the waveguide components. Alternatively, they can form any percentage thereof. For example, the first portions 92a, 94a and 96a can define anywhere from 5% to 95% of the inside shape of the waveguide components. Likewise, the second portions 92b, 94b and 96b can also define anywhere from 5% to 95% of the inside shape of the waveguide components. It should, however, be appreciated that although the proportion of the inside shape defined by each of the first portion and second portion can vary, the first portions 92a, 94a and 96a and the second portions 92b, 94b and 96b of the waveguide components together define 100% of the inside shapes of the waveguide components.
As shown in
In an alternative embodiment, the first waveguide portion 82 and the second waveguide portion 84 can be fastened together in a permanent manner, wherein the two mating rims 110a and 110b are joined together via welding, for example. In such an embodiment, the first waveguide portion 82 and the second waveguide portion 84 are joined such that they cannot be separated without causing damage to the two waveguide portions 82 and 84.
The configuration of waveguide assembly 80 differs from the configuration of waveguide assemblies 10 and 40. Specifically, the waveguide assemblies 10 and 40 have waveguide components that are arranged one after the other in a linear sequence, whereas the waveguide assembly 80 has waveguide components 92, 94 and 96 that are not positioned one after the other. Instead, in waveguide assembly 80, the harmonic filter 94 is positioned above the transmit filter 96. As best shown in
Referring back to
Referring to
Spacing of Components
Traditionally, each individual waveguide component (such as the isolators, e-bends, monitoring couplers, harmonic filters and transmit filters, described above) would have had two connecting interfaces or flanges (such as connecting interfaces 24, 48 and/or 86) positioned on each of its input and output ends. In this manner, in order to form a waveguide assembly, a series of waveguide components would be connected together via their connecting interfaces.
In accordance with the present invention, multiple waveguide components are included within a waveguide assembly that is formed of only a first portion and a second portion. As such, the waveguide components are positioned (or cascaded) next to each other within the waveguide assemblies 10, 40 and 80, such that there are no flanges or connecting interfaces between the waveguide components.
However, the waveguide components within the waveguide assemblies 10, 40 and 80 are still separated from one another by a separation space that will be referred to herein as a “matching network”. These matching networks are spaces included between the waveguide components in order to facilitate better phase matching between two adjacent waveguide components, and to reduce reflection losses or return losses in the waveguide assemblies.
With reference to the first and second waveguide portions 12 and 14 of the waveguide assembly 10 shown in
Likewise, with reference to the first and second portions 42 and 44 of the waveguide assembly 40 shown in
With reference to the first and second portions 82 and 84 of the waveguide assembly 80 shown in
By changing the dimensions (which could involve changing one or more of the height, width and depth) of the matching networks located between two adjacent waveguide components, a desired performance characteristic for the waveguide assembly can be more closely achieved. For example, based on the dimensions of the matching networks, the unwanted resonance created by the space between two adjacent components (Low pass filter and High pass filter) of the finished waveguide assembly can be set such that it is above or below the pass band. In addition, the dimensions of the matching networks can be determined in order to obtain a desired return loss for the waveguide assembly. As such, each matching network between two waveguide components will be designed taking into consideration its two adjacent waveguide components, so as to get a desired performance response for the entire waveguide assembly. When selecting the dimensions of the matching networks, sufficient margins can be built in so as to be able to compensate for machining tolerances.
As such, during the design phase of the waveguide assembly, the shape and configuration of the waveguide components, as well as the dimensions and positioning of the matching networks can be modeled together in order to better predict the interaction of the waveguide components once the waveguide assembly is manufactured. More specifically, the size, shape and dimensions of the matching networks can be modeled and optimized, such that the desired interaction and response of the overall waveguide assembly can be predicted. In certain circumstances, the shapes and configurations (or the input/output impedance) of the waveguide components can also be adjusted prior to manufacturing, in order to improve the performance response of the waveguide assembly.
As such, a person designing a waveguide assembly in accordance with the present invention will be able to adjust (within a given range) how the different waveguide components and matching networks will interact in order to give the desired performance response to the finished waveguide assembly. This can significantly reduce the amount of tuning that needs to be performed on the finished waveguide assembly. In addition, it allows a designer to adjust the phase matching of the waveguide components within the waveguide assembly prior to manufacture. This differs from conventional waveguide assemblies, where the response of the overall waveguide assembly will not be known until all of the waveguide components are assembled together via their respective flanges.
Shown in
In accordance with a non-limiting embodiment, the dimensions (height, width, depth) of the matching networks required in order to provide the desired response characteristics for the finished waveguide assembly can be determined using finite element software packages or mode matching software packages, which are commonly available off the shelf. These software packages determine the appropriate dimensions of the matching networks on the basis of at least one of the desired performance characteristics, such as resonance, reflection losses, return losses and/or phase matching, among other possibilities.
For example, in accordance with a non-limiting example of implementation, in order for the software package to determine the optimized dimensions for the matching network based on the desired performance characteristic, initial dimensions for the matching network are input into the computer. These initial dimensions can be obtained theoretically (based on Bode-Fano criteria). These initial dimensions are entered into the modeling software along with the desired performance characteristic or goal functions of the final waveguide assembly (such as the desired return loss). The outputs provided by the computer program will be the optimum dimension (height, width, depth) of the matching network(s) in order to achieve the desired performance characteristics of the final waveguide assembly.
In this manner, a waveguide assembly having desired performance characteristics (such as a desired return loss) can be modeled and optimized prior to manufacture. In order to improve and fine-tune the performance of the waveguide assemblies, tuning screws can be included between the waveguide components to add another degree of freedom for matching the phase of the overall waveguide assemblies. In general, these tuning screws will be located at the center of each matching network where the length and the height may need small adjustments.
By including multiple waveguide components within a waveguide assembly that is formed of only a first portion and a second portion, the capability of tuning each component, once manufactured, is compromised. However, the waveguide components and the matching networks can be modeled and optimized as a complete waveguide assembly prior to manufacturing in order to get as close as possible to the desired performance for the overall waveguide assembly. As such, the requirement to tune the waveguide assembly once it has been manufactured is greatly reduced.
Once the optimized design of the complete waveguide assembly is ready, the waveguide assembly is machined with a very high precision to get the closest dimension possible to the simulated and optimized model. By using this new approach, the interaction of the components contained within the waveguide assembly is no longer an unknown parameter that has to be dealt with at latest stage of the testing process (which was typically the case with conventional waveguide assemblies).
In addition, it has been found that waveguide assemblies in accordance with the present invention have lower return losses than conventional waveguide assemblies that are created by assembling multiple waveguide components via flanges or connecting interfaces. In general, it has been found that the entire insertion loss is improved over conventional waveguide assemblies, by 0.05 dB for every flange/connecting interface that is removed from the waveguide assembly. In addition, due to the fact that the waveguide assemblies of the present invention have removed the flanges/connecting interfaces from between the waveguide components, the multiple waveguide components are provided in a more compact space. For example, the waveguide assemblies 10, 40 and 80 are able to provide multiple different waveguide components in a smaller space than was traditionally possible by using connecting interfaces. This is due to the fact that the space taken up by the matching networks located between the waveguide components is less than the standard space that is occupied by connecting interfaces positioned between individual waveguide components.
In addition, waveguide assemblies in accordance with the present invention that include multiple different waveguide components therein, will be lighter than an arrangement of the same number of separate waveguide components that are connected together via the connecting interfaces. As such, the waveguide assemblies of the present invention require less space and are lighter than existing waveguide assemblies having the same functionality.
Order of Components
In each of the waveguide assemblies 10, 40 and 80 described above, the waveguide components are positioned in a specific order. For example, with respect to waveguide assembly 10, the e-bend 22 is positioned next to the transmit filter 20, which is positioned next to the harmonic filter 18, which is positioned next to the monitoring coupler 16. It should, however, be appreciated that these waveguide components could be positioned in any order without departing from the spirit of the invention. More specifically, depending on the performance requirements of a particular waveguide assembly, the shape, configuration and order of the waveguide components can be changed.
Method of Manufacture
In accordance with the present invention, the first portions and second portions of the waveguide assemblies are manufactured separately as two distinct pieces. In a specific, non-limiting example, each of the first and second portions are manufactured via machining processes using manual and/or CNC machines.
In order to achieve good functionality of the waveguide assemblies, the first portion and the second portion (such as first portion 12 and second portion 14 of waveguide assembly 10) are manufactured with very tight tolerances. In general, the entirety of the first portion and the second portion are manufactured in accordance with the tolerances specified for the most sensitive component of the assembly, which are generally the filters. The machining tolerances are chosen based on the margins and sensitivity analysis carried out by the mode matching or finite element software packages. In accordance with a non-limiting embodiment, and depending on the operating frequency band, the tolerances can vary from ±0.003 at L-band frequency to ±0.0002 at Q-band frequency.
In an alternative, non-limiting example, the first portions and second portions of the waveguide assemblies are manufactured via a casting process. In this embodiment, a mold is made for each of the first and second portions, and molten metal is poured into the molds for creating each of the two portions.
The two portions (namely the first portion and the second portion) of the waveguide assemblies can be made of stainless steel, aluminum, brass, copper or invar, among other possibilities. All of these materials can be plated with gold or silver, or any other suitable platting material.
Although the present invention has been described in considerable detail with reference to certain preferred embodiments thereof, variations and refinements are possible without departing from the spirit of the invention. Therefore, the scope of the invention should be limited only by the appended claims and their equivalents.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3866150 | Thai et al. | Feb 1975 | A |
| 4058780 | Riblet | Nov 1977 | A |
| 4069456 | Bensussan et al. | Jan 1978 | A |
| 4684908 | Kuntzmann et al. | Aug 1987 | A |
| 4697158 | Hoover et al. | Sep 1987 | A |
| 4701728 | Igarashi | Oct 1987 | A |
| 4801902 | Hoover et al. | Jan 1989 | A |
| 5469022 | Begum et al. | Nov 1995 | A |
| 6359792 | Genfan | Mar 2002 | B1 |
| 6407646 | Johnson | Jun 2002 | B1 |
| 6518851 | Kocharyan | Feb 2003 | B2 |
| 6710678 | Thormar | Mar 2004 | B2 |
| 7019706 | Yoneda et al. | Mar 2006 | B2 |
| 7176767 | Kroening | Feb 2007 | B2 |
| 7230507 | Kroening | Jun 2007 | B2 |
| 7242263 | Kroening | Jul 2007 | B2 |
| 7250835 | Higgins et al. | Jul 2007 | B2 |
| 7259640 | Brown et al. | Aug 2007 | B2 |
| 7280011 | Bayar et al. | Oct 2007 | B2 |
| 7332982 | Yun et al. | Feb 2008 | B2 |
| 7746189 | Hocine et al. | Jun 2010 | B2 |
| 20060261909 | Kroening | Nov 2006 | A1 |
| Number | Date | Country |
|---|---|---|
| 2007005955 | Jan 2007 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20100127804 A1 | May 2010 | US |
