Compactible antenna for satellite communications.

Abstract

The systems and methods described herein include foldable, deployable antenna structures that include shape-memory composite components.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 62 / 894,600, filed August 30, 2019, which is incorporated herein by reference in its entirety. [Background technology]

[0002] In recent years, several innovative companies around the world have pursued strategies to provide global coverage with large constellations of small satellites. These constellations seek to provide several different types of applications, including global internet availability, global commercial imaging capabilities, and global military situational awareness. A common requirement for these constellations, which can number hundreds of SmallSats, is the ability to communicate with the ground and with each other in a virtual network. Because the orientation of the satellites during deployment can be variable and unpredictable, it is preferable that the antennas used to transmit and receive signals operate in an omnidirectional manner.

[0003] A typical antenna is a rigid structure made of conductive metal. The nominal size of the antenna is conventionally on the order of the radio waves being received, which can be on the order of 10–15 centimeters for S-band frequencies. This is the size of a typical U CubeSat, which must also include electronics, cameras, power sources, and other components. This poses logistical challenges for satellites that are preferably stowed during launch and deployed once in orbit. Given their material construction limitations, such a retractable configuration of conventional antennas is difficult. As a result, antennas used for small satellites are usually extremely limited in size. Therefore, the antenna's beam pattern can be configured or narrowed to reduce size. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Application Publication No. 2016 / 0288453 Summary of the Invention [Means for solving the problem]

[0005] The antennas and satellites described herein may include a unique shape memory composite (SMC) material in the construction of the antenna design. Example embodiments may include an omnidirectional antenna design.

[0006] The disclosed exemplary embodiments use shape memory composites to construct compactible antennas for free-space communications between spacecraft and ground stations or between spacecraft and other spacecraft.

[0007] Exemplary embodiments include an antenna made of a shape memory composite material. The exemplary embodiment allows the antenna to transition from a deformed, stowed configuration to a deployed configuration. The deformed configuration may be a folded configuration or may otherwise define a smaller size or volume for storage or transportation. In exemplary embodiments, the shape memory composite material can have a memorized configuration such that the deformed configuration retains energy to deploy or transition the shape memory composite to a deployed configuration without external intervention or application of force. For example, a mechanism may be used to apply an external force to hold the shape memory composite material in the deformed configuration. When the applied force is removed, the shape memory composite material deploys.

[0008] In exemplary embodiments, the shape memory composite material may be electrically conductive to act as an antenna. Shape memory composite materials can be made electrically conductive through material selection of the fibers, resins holding the fibers, additives to the fibers and / or resin, coatings, and other methods described herein. The fibers may be electrically conductive. The resin may be electrically conductive. Metal or conductive powders, additives, or fillers may be added to the resin or fillers between the fibers. Metal strands may be incorporated with the composite fibers or used exclusively as the composite fibers. Thin metal foils may be coated or used to cover all or part of a shape memory composite member. Conductive paint or other coatings may be applied to all or part of the surface of a component made from a shape memory composite. [Brief explanation of the drawings]

[0009] [Figure 1] 1A-1C illustrate example antenna shapes according to embodiments described herein. [Figure 2] 1A-1C illustrate example antenna shapes according to embodiments described herein. [Figure 3] 1A-1C illustrate example antenna shapes according to embodiments described herein. [Figure 4] 1A-1C illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. [Figure 5] 1A-1C illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. [Figure 6] 1A-1C illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. [Figure 7] 1A-1C illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. [Figure 8]1A-1C illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. [Figure 9] 1A-1C illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. [Figure 10] 1A-1C illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. [Figure 11A] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 11B] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 11C] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 12] FIG. 1 illustrates an exemplary configuration according to embodiments described herein. [Figure 13A] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 13B] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 13C] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 14] FIG. 1 illustrates an exemplary system according to embodiments described herein. DETAILED DESCRIPTION OF THE INVENTION

[0010] The following detailed description illustrates the principles of the present invention by way of example, not by way of limitation. This description clearly enables any person skilled in the art to make and use the invention, and describes several embodiments, adaptations, modifications, alternatives, and uses of the invention, including what is presently believed to be the best mode for carrying out the invention. It should be understood that the drawings are diagrammatic and provide schematic representations of example embodiments of the invention and are not limiting of the invention, and that the drawings are not necessarily drawn to scale.

[0011] Exemplary embodiments can use dynamically deformable materials as support and deployment structures to support electrically conductive materials to create antenna configuration geometries.

[0012] In an exemplary embodiment, the dynamically deformable material may include an electrically conductive material to create an antenna configuration.

[0013] In an exemplary embodiment, the dynamically deformable material may not include electrically conductive material, but may support electrically conductive material in a desired configuration.

[0014] Exemplary embodiments may use an envelope contained within and / or supported by a dynamically deformable material. The envelope may be gas impermeable or semi-gas impermeable to allow expansion during deployment of the antenna. The envelope may be expanded to assist in transitioning the antenna to a deployed configuration. The envelope may be expanded to release the antenna from a stowed configuration. The envelope may act as a substrate to support an electrically conductive material to create the antenna configuration.

[0015] While embodiments of the present invention may be described and illustrated herein in terms of a specific antenna configuration, it should be understood that the present invention is not limited thereto and may further be applicable to different antenna configurations. Also disclosed are exemplary embodiments including different combinations of dynamically deformable materials as supports for the antenna, including conductive material, as spring supports for deploying the antenna from a stowed configuration, as supports for an envelope capable of supporting conductive material to create the antenna shape, as supports for the deployed configuration, and any combination thereof. Exemplary embodiments may include alternative features such as tear surfaces, removable retraction or storage materials or cords, envelopes, one or more antenna shapes, one or more sleeves or envelopes, one or more support substructures made of shape-memory material, hubs, one or more inflation mechanisms, and the like. Any feature, component, configuration, and / or attribute described with respect to any one example may be used in combination with any other example. Thus, any step, feature, component, configuration, and / or attribute may be used in any combination and still be within the scope of the description. Features may be removed, added, duplicated, combined, subdivided, or otherwise rearranged and still be within the scope of the description. The exemplary embodiments described herein are provided for purposes of example only. Thus, any of the antenna configurations may be used with or without an envelope according to the embodiments described herein. Any of the antenna configurations may be used with or without a tear-off or breakaway retention device according to the embodiments described herein. Any of the antenna configurations may be used with an inflation mechanism according to the embodiments described herein.

[0016] Although the exemplary embodiments are shown and described with respect to creating an omnidirectional antenna for free-space communications between a ground station and another spacecraft, other applications are within the scope of this disclosure, such as directional antennas. Other uses are also within the scope of this application, not just space communications between spacecraft.

[0017] If constructed from copper or some other conductive metal, the antenna is rigid and its "footprint" cannot be reduced for storage during launch. Exemplary embodiments described herein include shape memory components that can be dynamically deformed. Dynamic deformation, as described and used herein, includes unstructured deformation for storage and / or deployment. Exemplary embodiments of shape memory components can bend, curve, or otherwise deformed along the length of the shape memory component. The deformation can be along the entire length of the shape memory component or along a portion of the length. The dynamic deformation can be collapsed into a smaller configuration, stored in a SmallSat or other storage compartment, and released to unfold into a deployed configuration. In exemplary embodiments, the shape memory component has a memorized configuration. During use, exemplary embodiments can include a stored configuration, and the shape memory component can be held in the deformed shape through the application of an external force. When the external force, such as a deforming force, is removed, the shape memory component unfolds into the memorized configuration. The memorized configuration can be a deployed configuration. Deployment can therefore be easy for shape memory component structures, as deployment simply requires the removal of the mechanism that constrains the shape memory component (such as an antenna) in a folded or stowed configuration.

[0018] In an exemplary embodiment, the shape memory component can include a shape memory composite. The shape memory composite can include fibers held in a matrix or resin. The shape memory component can be electrically conductive. To improve the antenna gain, the electrical conductivity can be increased by: (1) adding a metal powder to the matrix of the composite; (2) adding a thin metal foil wrapped around the shape memory composite component that creates the antenna; (3) adding a conductive paint applied to the surface of the shape memory component; and combinations thereof.

[0019] 1-10 illustrate exemplary antenna configurations according to embodiments described herein. In exemplary embodiments, antenna structures 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 can include shape memory composites 12, 22, 32, 42, 52, 62, 72, 82, 92, 102. Shape memory composites can allow the antenna to collapse under an external force in an unstructured manner. Thus, the collapsed configuration can be dynamically determined based on the storage compartment or the applied external force. For example, shape memory composites can flex, or deform, along their length when a force is applied. However, the shape memory composites can return to their memorized configuration when the force is removed. In exemplary embodiments, the shape memory composites can flex at multiple locations along the length of the member or along the entire length of the member. In exemplary embodiments, the shape memory composite can return to a memorized configuration, such as a straight line, circle, oval, curve, parabola, spiral, volute, or other predefined shape, upon removal of the external force. The predefined shape may be the shape of the structure that is maintained without the use of an external force. The predefined shape may be defined through relationships and connections with one or more other shape memory composites, envelopes, and / or other support structures described herein.

[0020] Exemplary shape memory composite materials include a substrate of one or more of carbon fiber, Vectran, Kevlar, fiberglass, fiberglass, plastic, or fiber metal. The substrate can include strands. The strands may be generally aligned along the length of the structure, may include one or more aligned configurations, may be wrapped or spirally arranged, may be woven, or any combination thereof. The shape memory composite material can include a matrix around the substrate and / or between the substrates. The matrix can be silicone, urethane, or epoxy. Exemplary shape memory composite materials are described in commonly owned patent application U.S. Patent Publication No. 2016 / 0288453, entitled "Composite Material." Exemplary embodiments include a high-strain material to accommodate deformation. A high-strain material typically has the ability to strain more than 3% without entering plastic deformation. In other words, the material can be deformed more than 3%.

[0021] In exemplary embodiments, the shape memory composite material includes a fiber-to-resin volume fraction that can be controlled to achieve desired shape memory retention, even after extended storage in a folded / packaged state. An exemplary fiber-to-resin volume fraction is 52 to 65, i.e., 52 to 65 percent fiber or 48 to 35 percent matrix or resin. The average fiber-to-matrix ratio is about 58 percent. The fiber may be carbon, Kevlar, Vectran, nylon, etc., as described herein, and the resin may be urethane, silicone, epoxy, etc., as described herein as the matrix.

[0022] In an exemplary embodiment, a member constructed from a shape memory composite material may be electrically conductive to define the antenna shape. All portions of the component may be electrically conductive. The component may be made electrically conductive by incorporating an electrically conductive material into the shape memory material. The component material may include a metal powder, coating, wrapping, sheet, film, paint, strand, or combinations thereof. The electrically conductive material may be present in the fibers, resin, on the surface of the fibers, on the surface of the component material, or combinations thereof. In an exemplary embodiment, the shape memory composite component is electrically conductive to create the antenna shape by wrapping the component with a thin sheet of copper. The copper sheet may be glued or otherwise bonded to the exterior surface of the shape memory composite shaft.

[0023] FIG. 1 illustrates an exemplary embodiment of an antenna structure 10 in which a conductive material is configured as a quadrifilar (four helical conductor) helical antenna. As shown, the antenna structure includes a shape memory member 12 comprising a conductor. The conductive member defines four helical strands wrapped around a longitudinal central axis. The longitudinal central axis may include a conductive shaft. Opposite ends of the quadrifilar may include radial extensions connecting the individual helical strands to the longitudinal axis or central shaft at their opposite ends. The helical strands may be circumferentially offset by 90 degrees. Having helical strands as well as a central shape made of a shape memory composite allows the entire structure to deform to fit within a desired storage space and to bend in any unstructured, or random, configuration.

[0024] FIG. 2 illustrates an exemplary embodiment of an antenna configuration 20 defining a biconical antenna. As shown, the antenna may include a hub 24. A longitudinal axis extends in opposite directions on either side of the hub or center. The longitudinal axis may include a conductive shaft. As shown, five conductive members extend radially and longitudinally away from the hub on either side of the hub. The five conductive members may extend radially outward a certain distance and then extend radially inward to connect to the shaft or longitudinal axis. The radially inward extending portions of the conductive members may extend only radially inward, such that the conductive members define a portion of a right triangle. The conductive members may also continue to extend longitudinally away from the hub as they extend radially inward, thus defining other curved or triangular shapes.

[0025] FIG. 3 illustrates an exemplary antenna configuration 30. The conductive material may be present within a shape memory component 32, as described herein. The conductive material may define one or more rectangular, square, quadrilateral, or other geometric shapes. The shapes may be arranged such that the plane of the shape includes or passes through the longitudinal axis. The shapes may be circumferentially offset or may be arranged around the longitudinal axis. The longitudinal axis may define or be the conductive shaft.

[0026] 4-10 illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. The exemplary embodiments shown illustrate exemplary embodiments of the support structure described herein with dashed lines. The support structure is shown with different line types to distinguish component parts for illustrative purposes and to improve understanding of the invention. The dashed lines are not shown to suggest or represent holes or apertures in the support structure, although the support structure may include such features. In exemplary embodiments, the support structure is gas impermeable as described herein.

[0027] In exemplary embodiments, the antenna structures 40, 50, 60, 70, 80, 90, 100 may be supported by support structures 46, 56, 66, 76, 86, 96, 106. The support structures 46, 56, 66, 76, 86, 96, 106 may be conductive or non-conductive. The support structures may provide other features for the antenna, such as shape support, signal effect, directional effect, storage retention, deployment actuation, or a combination thereof. In exemplary embodiments, the support structures comprise flexible membranes. Thus, the support structures may be foldable and / or deformable in the same or similar manner as the antenna structures. The support structures may be dielectric membranes. The support structures may be fabrics, meshes, or sheets. The support structures may be Kapton, Mylar, Teflon, cotton, or other dielectric and / or non-conductive materials. Although shown as included with only a subset of exemplary embodiments, the support structures may be used with any antenna configuration described herein. The support structure may be coupled to the shape memory composite, the conductive component, other components of the antenna, or a combination thereof.

[0028] In exemplary embodiments, the support structures 46, 56, 66, 76, 86, 96, 106 define a thin surface. The support structures 46, 56, 66, 76, 86, 96, 106 may include flexible materials coupled to any combination of other additional support structures, support structures, shape memory composite components, and / or conductive components. In exemplary embodiments, the support structures 46, 56, 66, 76, 86, 96, 106 define a gas-impermeable or semi-gas-impermeable surface. The support structures may define an internal cavity. The support structures may be arranged to create a continuous gas-impermeable surface around the internal cavity. In exemplary embodiments, the support structures may be inflatable, as described more fully herein. In exemplary embodiments, the support structures may be inflatable to aid in deployment of the antenna structure. The support structures may be configured to vent inserted fluid after inflation and / or to retain fluid for a period of time after inflation. Thus, a gas impermeable surface may include a surface that retains sufficient gas to aid in deployment and initial inflation, but allows the gas to vent thereafter.

[0029] 4-6 illustrate exemplary configurations in which shape memory components 42, 52, 62 are disposed on the surface of support structures 46, 56, 66. FIG. 4 illustrates an exemplary cylindrical support structure 46 having one spiral conductive component made of shape memory composite 42. Other spiral configurations can also be added to the support structure (such as the configuration of FIG. 1). FIG. 5 illustrates an exemplary conical support structure 56 having one spiral conductive component made of shape memory composite 52 bonded to the support structure such that the diameter of the spiral conductive component tapers from one end of the antenna to the opposite end. The conical support structure can be brought to a point or can terminate to a smaller diameter end before coming to a point. Other spiral configurations can also be added to the support structure.

[0030] Exemplary embodiments can also use combinations of dielectric and / or non-conductive layers to create composite antenna configurations with leads that may overlap each other but may or may not be in contact with each other. For example, a first cylindrical support structure can be used with a conductive material, either on its interior or exterior surface. A second cylindrical support structure can be disposed on or inside the first cylindrical support structure, enclosing the conductive material between the first and second layers. The other side of the second cylindrical support structure, opposite the side in contact with the enclosed conductive material, can also include a conductive material. Thus, an antenna can include a first conductive layer, a non-conductive and / or dielectric layer defining a first pattern, and a second conductive layer defining a second pattern. The antenna can include additional combinations of conductive and non-conductive and / or dielectric layers. Different layers can be used to create composite antenna configurations and to create different conductive patterns that can be electrically coupled and / or electrically isolated.

[0031] FIG. 6 illustrates an exemplary configuration having multiple support structures 66 and conductive members made of shape memory composite components 62. As shown, different antenna shapes can be created. As can be seen in FIG. 6, the first antenna-shaped portion defines multiple radially extending conductive components 62A. The second antenna-shaped portion defines multiple radially and longitudinally extending conductive components 62B, creating a generally conical configuration. The first support structure can define a generally cylindrical shape, while the second support structure can define a generally conical shape. Each of the conductive components can be coupled to a surface of the support structure. The support structures can define separate volumetric cavities. The cavities of the support structures can be connected or isolated. The volumetric cavities can be used to deploy and / or support the antenna according to the deployment methods described herein.

[0032] FIG. 7 illustrates an exemplary antenna structure 70 having the same conductive pattern as the antenna structure 60 of FIG. 6 . However, the shape of the support structure 76 is different to support the antenna conductive shape memory conductive components 72. As shown in FIG. 7 , at least some of the conductive and / or shape memory composite components, or portions thereof, are off the surface of the support structure and only partially contact the support structure to support it. As shown, the support structure 76 defines a partial cone, or truncated cone. Radial conductive and / or shape memory composite components 72A are disposed along the entire surface of the support structure 76. However, radially, longitudinal conductive and / or shape memory composite components 72B extend within the support structure, away from the surface of the support structure 76. The conductive and / or shape memory composite components 72B are coupled at their terminal ends to the edges of the support structure 76.

[0033] FIG. 8 illustrates another exemplary antenna structure 80 having a support structure 86. The antenna structure 80 may be similar to the antenna structure of FIG. 3 having a similar conductive and / or shape memory composite component 82 as component 32. The antenna structure 80 may also include a combination of a first component segment 82A extending along a surface of the support structure 86 and a second component segment 82B extending within the support structure 86. Those skilled in the art will recognize that other support structures 86 may also be used. For example, an annular support structure having a cross-sectional shape (i.e., the quadrilateral shown) that approximates the conductive and / or shape memory composite component segment may be used.

[0034] As shown in FIGS. 9-10 , the antenna may be defined by conductive traces formed on a support structure. The traces may be made of a conductive material. The traces may be made of a coating, fiber, wire, paint, or other structure supported on and / or within and / or through the support structure. The design of the antenna structures 90, 100 may be separated so that design considerations for support are maximized while those for the antenna are also maximized. By decoupling the conductive material from the shape memory composite support structure, both design considerations may be improved. For example, fewer shape memory composite components may be used, thus minimizing the retracted configuration while maintaining antenna response with an appropriate number of conductive components. For example, the shape memory composite components 98, 108 may be selected to improve support and / or deployment of the antenna structures 90, 100, while the conductive components 92, 102 may be selected and positioned on the support structures 96, 106, shape memory composite members, or intermediate members to improve antenna function.

[0035] As shown in FIG. 9 , the antenna structure 90 can also include an additional support structure 99. The additional support structure can include a flexible material coupled to any combination of other additional support structures, support structures, shape memory composite components, and / or conductive components. The additional support structure can be used to support conductive components that may or may not be disposed on the support structure. In an exemplary embodiment, the additional support structure can be a string, an elongated flexible member, a wire, a band, or a combination thereof. The additional support structure can be used to reinforce one or more of the additional support structures, support structures, shape memory composite components, and / or conductive components. The additional support structure can be used to affect the shape, e.g., the deployed shape, of any combination of the additional support structures, support structures, shape memory composite components, and / or conductive components. For example, as can be seen in FIG. 9 , the additional support structure 99 can be used to reinforce the support structure 96 and also to create a reduced diameter cross-section by coupling the additional support structure 99 and / or support structure 96 to the interior of the antenna structure 90. Thus, additional support structures can be used to create complex shapes for use with novel antenna designs.

[0036] In an exemplary embodiment, the shape memory composite material may be integrated with a support structure. The shape memory composite material may create a support structure.

[0037] In exemplary embodiments, the shape memory composite material can create a framework to which a support structure is attached. As described herein, the shape memory composite can reside within the support structure or can be bonded along the entire support structure. Also, the shape memory composite component can be bonded to the support structure along a portion or point of the shape memory composite component. A combination of support structures and / or shape memory composite components can be used.

[0038] In exemplary embodiments, a conductive material may be combined with the shape memory composite component. The conductive material may be present within and / or on the surface of the shape memory composite, as described herein.

[0039] In exemplary embodiments, the conductive material may be supported by or on a support structure. The conductive material may be disposed on, within, and / or coupled to the support structure, such as on the surface of the support structure, in any manner. In exemplary embodiments, the conductive material may be painted, coated, disposed on, woven into, or otherwise coupled to the support structure. For example, the conductive material may include thin copper sheet metal. The sheet metal may be patterned on, disposed on, or coupled to the surface of the support structure. As another example, the conductive material may be a thin copper wire fiber. The fiber may be woven into or coupled to the support structure.

[0040] In exemplary embodiments, additional structures may be used to deform and / or support the support structure and / or conductive components. In exemplary embodiments, the additional structures may include flexible components, which may also be shape-memory or non-shape-memory. The additional support structures may be coupled to the shape-memory components and / or support structures to bond the component parts together, define the deployed shape, support or create additional attachment points between the component parts, affect deployment, and otherwise contribute to the design of the antenna structure.

[0041] The exemplary embodiments described herein may use any combination of the features described herein. In exemplary embodiments, the antenna structure may include any combination of support structures, shape memory composite components, conductive components, and additional structures, whether separate component parts and / or component parts integrated in one or more ways so that a single component part functions as two or more component parts. Exemplary embodiments include any combination of support structures, shape memory composite components, conductive components, and additional structures with flexible components. Flexible components include component parts that can bend at any point or along their length. In exemplary embodiments, any combination of support structures, shape memory composite components, conductive components, and additional structures allows for unstructured dynamic deformation. As described herein, unstructured dynamic deformation allows for deflection that can be defined in a non-preconfigured or non-structurally constrained manner by external forces that deform the components.

[0042] 11A-12 illustrate exemplary embodiments of antenna systems 110, 120 including housings 111, 121A, 121B. The housings can be used to apply an external force to hold the antenna in a stowed configuration. Exemplary embodiments of the housings can be opened to remove the deforming force and allow the shape memory component to unfold. The system can include an opening mechanism for opening the housing. The opening mechanism can include a hinge, a pyrotechnic door, an explosive bolt, a failure component, or any other system for restraining the antenna in its stowed state. In exemplary embodiments, the failure component is configured to withstand at least a threshold amount of applied force. The failure component is configured to intentionally fail when a force exceeding the threshold amount is applied. The failure component can be configured to apply a deforming force to restrain the shape memory component. The system can be configured to apply an additional force to deploy the antenna configured to overcome the threshold amount and fail the failure component, releasing the antenna.

[0043] 11A-11C illustrate an exemplary deployment sequence according to embodiments described herein.

[0044] 11A, in which the antenna structure 112 is held in a retracted position having a reduced storage volume through the application of an external force; and, as seen in FIG. 11C, in which the antenna structure is fully deployed, having a larger volume when the external force is removed. In other words, the memorized, or biased, configuration may be a deployed configuration in which the antenna structure is configured for use as a deployable quadrifilar antenna configuration (as shown in FIG. 1) or other compact antenna configuration (as shown in FIGS. 2-13B or otherwise configured according to embodiments described herein). The antenna structure 112 may be disposed within the housing 111 in the retracted configuration in an unstructured, deformed configuration.

[0045] As can be seen in FIG. 11B , the housing 111 may be opened or otherwise configured to remove the holding force on the antenna structure 112. In an exemplary embodiment, the housing may include a first part 111A and a second part 111B, and the first and second parts may be separable. The first part 111A may be coupled to the second part 111B in the stowed configuration to provide a deformation force to hold the antenna structure in the stowed configuration. The first part 111A may be opened and / or separated from the second part 111B. When opened, the first part 111A may be held to the second part 111B, such as by a hinge or other connection. As shown in FIG. 12 , the first part 121A may be completely separated from the second part 121B. The first part and / or the second part may create a support substructure and / or a hub component for the antenna system.

[0046] 11C, once the deforming force is removed, the antenna structure 112 can fully deploy. Deployment may be through the removal of a deforming force, such as that imparted to a shape memory composite component by a retention device. The retention device may be a housing or part of a housing and / or another component part described herein.

[0047] FIG. 12 illustrates an exemplary configuration according to embodiments described herein. FIG. 12 illustrates an exemplary antenna structure 120 including a shape memory composite component 122 and a support structure 126. The antenna structure 120 can include an outer housing configured to enclose the shape memory composite component and / or the support structure. The outer housing 123 can include portions that can be separated into a first portion 121A and a second portion 121B. The housings can be coupled together through a failure interface. For example, the failure can be through the application of a substance, an explosion, an ignition, or an additional force. The failure interface can be configured to hold the shape memory composite component in a stored, deformed configuration. The failure interface can be configured to fail under a desired condition. Upon failure, the shape memory composite material reverts to a memorized state, allowing the antenna structure to be deployed to a deployed configuration.

[0048] In an exemplary embodiment, the support structure can define a gas-impermeable cavity. During deployment, a fluid can be injected into the support structure to inflate it. The expansion of the support structure can be used to overcome the failure interface and release the antenna structure for deployment. The expansion of the support structure can assist in the deployment of the shape memory composite material into a memorized configuration. The expansion can be used to counter any creep or deformation that may occur in the antenna structure during long-term storage. The support structure can then release the expanded fluid over time. However, the shape memory composite material can then provide sufficient support to the antenna structure such that additional inflation fluid is not required to maintain the shape of the antenna structure during long-term deployment.

[0049] 13A-13C illustrate an exemplary deployment sequence according to embodiments described herein. Similar to the deployment shown in FIGS. 11A-11C, the antenna structure can include a shape memory composite component 132 that assumes a stowed configuration upon application of a deforming force. When the deforming force is removed and / or using a support structure defining an envelope that receives inflation fluid, the antenna structure deploys and the shape memory composite component returns to its memorized configuration.

[0050] In an exemplary embodiment, the antenna structure is held within housings 131A, 131B, as seen in FIG. 13A. The housing can be a rigid structure to hold the antenna structure, including the shape memory composite component, and to provide retention to the antenna structure. FIG. 13A shows that the housing can include a first part 131A to partially enclose the antenna structure, with a second part 131B acting as a cover or lid for the first part 131A. The lid can be used to support or provide retention to the antenna structure for long-term storage.

[0051] Once ready for use and transport to space, second part 131B can be removed from first part 131A, as seen in FIG. 13B. First part 131A can thus define a first retention device for long-term storage. Long-term storage includes a time duration unknown herein, which may be a matter of minutes, hours, days, weeks, months, or years. In an exemplary embodiment, second retention device 131C provides a deformation force to continue to hold the antenna structure in a stowed configuration. Second retention device 131C can be used for short-term retention of the antenna structure. In an exemplary embodiment, short-term retention may be for a known, finite duration, even if the short-term retention is on the order of hours, weeks, months, or even years. As shown, second retention device 131C includes failure interface 133. The failure interface can be configured to tear, break, dissolve, or otherwise fail to allow the antenna structure to return to a memorized configuration. As shown, the second retention device 131C can define a thin covering sheet that includes a weakened portion that acts as the failure device 133. The weakened portion can include a portion of material that is perforated and therefore withstands less external force. Other configurations, such as thinner material cross-sections, holes, tears, degradable materials, temperature sensitive materials, and combinations thereof, may also be used and are within the scope of the present disclosure.

[0052] FIG. 13C illustrates the deployment of the antenna structure as the shape memory material 132 overcomes the deformation force of the retention device 131C, such that the retention device 131C fails and the deformation force is removed. In an exemplary embodiment, the antenna structure includes a support structure 136 defining an expansion sleeve. The expansion sleeve may be inflated by injecting one or more fluids, such as a gas, to apply additional force to the retention device 131C to overcome the failure interface 133. Thus, injecting a fluid into the expansion sleeve can release the antenna structure from a stored configuration and allow the shape memory composite component to return to a memorized configuration. Injecting a fluid into the expansion sleeve can also assist in the return of the shape memory composite component to a memorized configuration. The expansion sleeve can be inflatable or hold an expansion gas for a period of time to overcome or counteract potential creep in the shape memory composite component or other shape retention of any component that the antenna structure may experience from a longer duration of time.

[0053] FIG. 14 illustrates an exemplary system according to embodiments described herein. As shown, an antenna system 140 can include one or more components within a housing 141. The housing 141 can be used for long-term storage. The housing can include a door 142. The door 142 can provide a deformation force to the antenna structure to hold the antenna in a stowed configuration. The housing and / or its door can be used to provide additional retention force in addition to the deformation force provided by the other component parts described herein. The additional retention force may be used for long-term storage and / or to provide additional environmental protection for the antenna assembly while stored in a terrestrial environment. Thus, the housing can be sealed between the housing 141 and the door 142. The door can be completely removed or simply opened using a hinge 143 or the like.

[0054] An exemplary embodiment of the system may include electronics for controlling portions of the system. For example, the sequencer 144 and / or electronics may include a communication system; an interface system for coupling to other electronic systems; a controller; a sequencer; and combinations thereof. The sequencer and / or electronics may communicate with the controller and / or allow for the operation of one or more of the system components described herein. For example, the controller may interface with a fluid injection system to inflate the inflation envelope described herein. For example, the controller may interface with a release mechanism for the antenna structure to remove the deforming force and allow the antenna structure to return to a memorized configuration. This may be by opening the housing door 142, by igniting an explosive to remove another faulty component, by inflating the inflation envelope with fluid to overcome a faulty interface, or a combination thereof.

[0055] An exemplary embodiment of the antenna system may include one or more actuators 145 for controlling one or more components of the system. As shown, an exemplary actuator may include a compressed gas canister and a controller. The compressed gas canister may be in fluid communication with the interior of the cavity of the inflation envelope created by the support structure described herein.

[0056] An exemplary embodiment of the antenna system can include an antenna structure 146. The antenna structure 146 can include one or more component parts including any combination of shape memory composite components, conductive components, support structures, housings, additional support structures, and the like.

[0057] Antenna designs according to embodiments described herein can transmit and receive circularly polarized waves, which may be preferable for traveling through the ionosphere because magnetic fields generated in the ionosphere by charged particles induce Faraday rotation in linearly polarized beams.

[0058] Antenna designs according to embodiments described herein may be omnidirectional to accommodate any satellite orientation. Different antenna designs are provided and described herein merely by way of example. Some examples can provide both circular polarization and / or omnidirectionality. For example, an exemplary antenna design capable of providing both circular polarization and omnidirectionality can include a helical-shaped conductive component and / or define a biconical horn. Exemplary embodiments can use polarized feeds. Exemplary helical designs include the quadrifilar (four helical conductor) helical antenna shown in FIG. 1. An exemplary biconical antenna design is shown in FIG. 2.

[0059] It should be emphasized that many variations and modifications may be made to the embodiments described herein, and that these elements are to be understood as particularly acceptable examples. All such modifications and variations are intended to be included within the scope of this disclosure herein and protected by the following claims. Furthermore, the steps described herein may be performed all at the same time or in a different order than the order of the steps described herein. Furthermore, it will be apparent that the features and attributes of specific embodiments disclosed herein may be combined in different ways to form additional embodiments, all of which are within the scope of this disclosure.

[0060] For reference purposes only, certain terminology may be used in the following description and is not intended to be limiting. For example, terms such as "upper" and "lower" refer to directions in the drawings to which reference is made. Terms such as "front," "rear," "left," "right," "behind," and "side" describe the orientation and / or location of a component or portion of an element within a consistent, but arbitrary, framework that is clearly referenced by reference to the text and associated drawings that describe the component or element under discussion. Additionally, terms such as "first," "second," "third," etc. may be used to describe individual components. Such terminology may include, among others, the above-mentioned words, derivatives thereof, and words of similar import.

[0061] As used herein, conditional language, such as, inter alia, "can," "could," "may," "for example," etc., is generally intended to convey that a particular embodiment includes a particular feature, element, and / or condition, unless specifically stated otherwise or as otherwise understood within the context in which it is used. However, such language also includes embodiments in which the feature, element, or condition is absent. Thus, such conditional language is generally not intended to imply that a feature, element, and / or condition is necessarily required for one or more embodiments, or that one or more embodiments necessarily exclude undescribed components from another embodiment.

[0062] Additionally, the following terminology may be used herein: The singular forms "a," "an," and "the" include plural referents unless the context clearly indicates otherwise. Thus, for example, a reference to an item includes a reference to one or more items. The term "ones" means one, two, or more and typically applies to the selection of some or all of a quantity. The term "plurality" means two or more of an item.

[0063] As used herein, the terms "about," "substantially," or "approximately" in connection with any numerical value, range, shape, distance, relative relationship, etc., indicate an appropriate dimensional tolerance within which a portion or collection of components can function for its intended purpose as described herein. Numerical ranges may also be provided herein. Unless otherwise indicated, each range is intended to include the endpoints and any quantity within the provided range. Thus, the range 2-4 includes 2, 3, and 4, as well as any subdivision between 2 and 4, such as 2.1, 2.01, and 2.001. Ranges also encompass any combination of ranges, such as 2-4 including 2-3 and 3-4.

[0064] As used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are inclusive. These terms are not to be interpreted to exclude the presence of other features, steps or components.

[0065] The features expressed in the foregoing description, or in the following claims, or in the accompanying drawings, in their specific forms or means for performing a disclosed function or method or process for achieving a disclosed result, may, as appropriate, be used individually or in any combination to realize the invention in its diverse forms.

[0066] Although the embodiments of the present invention have been fully described with reference to the accompanying drawings, it should be noted that various changes and modifications will become apparent to those skilled in the art. It is understood that such changes and modifications are included within the scope of the embodiments of the present invention, as defined by the appended claims. Specifically, exemplary components are described herein. Any combination of these components may be used in any combination. For example, any component, feature, step, or part may be integrated, separated, subdivided, removed, duplicated, added, or used in any combination and remain within the scope of the present disclosure. The embodiments are merely exemplary and provide illustrative combinations of features, but are not limited thereto.

Claims

1. a base structure comprising a shape memory component; a conductive component; a support structure that creates an expansion sleeve, the base structure and the conductive component contacting the support structure; a storage device configured to apply a deformation force to the base structure to hold the base structure in a stored configuration; a failure device coupled to the storage device, the support structure being configured to transition the base structure from the stored configuration to the deployed configuration by destroying the failure device; An antenna structure comprising:

2. The antenna structure of claim 1 further comprising a support structure coupled to the shape memory component.

3. The antenna structure of claim 2 , wherein the antenna structure has a stowed configuration and a deployed configuration, and the shape memory component is non-conformationaly deformed in the stowed configuration.

4. The antenna structure of claim 3 , wherein the conductive component is a conductive material on the outer surface of the shape memory component.

5. The antenna structure of claim 1 , wherein the support structure comprises a gas impermeable material.

6. The antenna structure of claim 5 , wherein the shape memory component comprises a plurality of shape memory components that create four helical curves to define a quadrifilar antenna.

7. The antenna structure of claim 5 , wherein the shape memory component comprises a plurality of shape memory components defining a biconical antenna.

8. storing the antenna structure having a shape memory composite component and a conductive component and a support structure creating an expansion sleeve in a stored configuration; inflating the inflation sleeve with inflation gas to transition the antenna structure from a stowed configuration to a deployed configuration that defines an antenna shape; Destroying the failed device by expansion of an expansion sleeve, the failed device being coupled to a storage device that applies a deformation force to the antenna structure to hold the antenna structure in a storage configuration; maintaining a deployed configuration that defines the antenna shape with a shape memory component; and 1. A method for deploying an antenna structure, comprising:

9. The method of claim 8 , wherein the antenna geometry is configured to provide both circular polarization and omnidirectionality.

10. The method of claim 9 , further comprising applying a deformation force to the antenna structure to non-structurally deform the shape memory composite component.

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