The invention relates to communication devices and methods of manufacturing communication devices. More particularly, the invention relates to integrated electronic scanning arrays (ESA) and methods of manufacturing the same.
Communication systems have been developed for a wide variety of different applications. For example, communication systems employed on an aircraft include in-flight operations systems such as global broadcast systems (GBS) and in-flight entertainment (IFE) systems that supply television and Internet to aircraft passengers. Wireless IFE systems display video and data information received from low power signals. Accordingly, some IFE systems include liquid crystal display (LCD) systems as well as antennas.
One type of antenna which can be used in communication systems is an electronic scanning array (ESA). An ESA typically includes many small antenna elements which, when correctly phased using electric circuits, form electromagnetic beams of radio waves for transmission or reception.
Traditionally, ESAs have not been widely used because they are inherently very costly to make. For example, an ESA for a single IFE passenger unit can cost over $10,000 to manufacture. More precise ESA systems cost over $1 Million to manufacture. Larger arrays require heavy support structures and complicated manufacturing procedures.
In addition to cost issues, another important design limitation for conventional systems is the volume needed to have both a display and an antenna co-located. Many applications, including in-flight systems, laptop computers, handheld devices, and other communication devices, are limited in the amount of space available for a display, an antenna, and other electrical components. For example, a handheld device used by a soldier or a hiker should be as compact as possible. Separate display, receiver, and many antenna elements would be unwieldy for such a handheld device.
In the area of GBS, global positioning systems (GPS), and other satellitebased systems, however, it is not known to integrate the display, a portion of the receiver, and antenna in a small form factor. Furthermore, although it has been suggested to use a flexible display that can be conveniently stored in a pocket, users of satellite-based systems also require a portable satellite antenna as well as a receiver. In other applications, such as airborne or vehicle-mounted applications, larger antennas may be used, but space considerations often preclude the use of larger antennas. In addition, such larger antennas may impair a mobile platform's performance by adding drag to an aircraft on which the antenna is mounted.
It is therefore an object of the invention to manufacture electronic scanning arrays (ESA) in a less expensive manner.
It is another objective of the invention to provide an antenna which can be integrated as part of the display.
A feature of the invention is a transparent, flexible electronic scanning array that may be integrated into a display during the manufacturing of the display.
Another feature of the invention is embedding an antenna in a flexible display, thereby combining a display, receiver, and antenna into a single light, portable flexible display.
An advantage of the invention is that a large ESA may be inexpensively manufactured and used on a mobile platform, such as an aircraft, without degrading aircraft performance due to drag associated with radomes.
The invention provides a method of forming a conformal electronic scanning array. According to the method, a plurality of receptor structures are established in a substrate. A first conductive passage is created through the substrate and is associated with each receptor structure. A plurality of transmit/receive circuitry units are applied to a surface of the substrate such that each of a substantial portion of the receptor structures are filled by a transmit/receive circuitry unit disposed therein, and a first electrical contact on each transmit/receive circuitry unit is positioned to be electrically connected with the first conductive passage. A first dielectric layer is applied to the surface of the substrate. A first conductive layer is applied to the first dielectric layer. A second dielectric layer is applied to the first conductive layer. A second conductive layer applied to the second dielectric layer and is etched to form a plurality of radiating elements. Each of the plurality of radiating elements is disposed adjacent one of the plurality of transmit/receive circuitry units such that a radiating element, a second contact on a transmit/receive circuitry unit, and the first conductive ground plane, cooperate to form an active radiating element controlled by the transmit/receive circuitry unit.
The invention also provides a conformal electronic scanning array, including a substrate having a first surface and a second surface. A plurality of receptor structures are formed in the substrate. A plurality of vias are formed in each receptor structure, through the substrate. A plurality of transmit/receive circuitry units are applied to the first conductive layer and are operative to fit into any of the plurality of receptor structures. Each of the transmit/receive circuitry units have a plurality of electrical contacts disposed thereon. Each of the transmit/receive circuitry units are configured to accommodate at least one of sending and receiving electronic communications. The plurality of vias are configured to be aligned with a corresponding number of electrical contacts disposed upon a transmit/receive circuitry unit that fits into the respective receptor structure to provide at least one of a power input and a control input thereto. An antenna element is operationally connected to the transmit/receive circuitry unit.
The invention further provides an electronics device including a display component and a conformal electronic scanning array secured to a viewable surface of the display component between the display and a viewer. The conformal electronic scanning array includes a substrate having a first surface and a second surface. A plurality of receptor structures are formed in the first surface of the substrate. A plurality of vias are formed in each receptor structure, through the substrate. A plurality of transmit/receive circuitry units are applied, in a slurry, to the first surface of the substrate and are operative to fit into any of the plurality of receptor structures, wherein each of the transmit/receive circuitry units has a plurality of electrical contacts disposed thereon. The plurality of vias are aligned with a corresponding number of electrical contacts disposed upon a transmit/receive circuitry unit when the circuitry unit is set in a receptor structure, so that the plurality of vias provide at least one of a power input and a control input to the transmit/receive circuitry unit. A first dielectric layer is applied on the transmit/receive circuitry units. A first conductive layer is applied on the first dielectric layer. A second dielectric layer is applied on the first conductive layer. A second conductive layer is applied to the dielectric layer and is etched to form a plurality of radiating elements. Each of the radiating elements is associated with an RF contact on one of the transmit/receive circuitry units to form an active radiating element therewith. The substrate, the dielectric layer and the first and second conductive layers are substantially transparent.
Other features and advantages of embodiments of the present invention will become apparent to those skilled in the art upon review of the following drawings, the detailed description, and the appended claims.
The invention contemplates a substantially transparent, conformal electronic scanning array (ESA) that can be placed upon any number of surfaces. The ESA includes a plurality of printed or slot-type antenna elements arranged in a grid or other predetermined pattern, with associated circuitry aligned with each antenna element. As the number of antenna elements included in the conformal ESA of the present invention may number in the thousands or even millions, to ease understanding the specification and figures will principally describe the manufacture of a single antenna element. However, the invention is designed to use the disclosed methods to manufacture a conformal ESA including any feasible number of antenna elements, and the scope of the present invention should be considered to include such a conformal ESA.
First and second passages or vias 22, 24 are formed, preferably using a laser or known etching processes, through third dielectric layer 20, dielectric material filling first and second holes 18b and 18a, second dielectric layer 16, and circuitry voids 12b and 12c, respectively. First and second vias 22, 24 are then preferably filled or coated with an electrically conductive substance to provide an electrical connection between the ends of the respective first and second vias. First and second vias 22, 24 are isolated from the first ground plane 18 by material from third dielectric layer 20 filling first and second holes 18a, 18b. A power/control manifold layer 26 is applied to a lower surface 20a of third dielectric layer 20. Power/control manifold layer 26 may be made of ITO and, as shown in
The portion of the antenna element disclosed thus far provides a series of manifolds to supply the antenna element with the required power and control signals, as well as to communicate an RF signal to or from the antenna element. These manifold layers and dielectric layers have been described as being applied to the lower surfaces (as seen in the Figures) of previously disclosed layers. Layers built upon the upper surfaces (as seen in the Figures) of previously disclosed layers will now be discussed. It is to be understood that, in accordance with known manufacturing techniques, layers may be also applied either alternatingly or simultaneously on upper and lower surfaces of previously applied layers.
As shown in
Each T/R chip has a lower surface 40a and an upper surface 40b. Lower surface 40a is designed to enter receiving depression 30. As shown in
Even with the complementary shapes of the receiving depression and the T/R chip, the T/R chip may be inserted into the receiving depression two opposite ways. To ensure the contacts on the T/R chip will be properly connected, a set of alternate electrical contacts 44a′, 44b′, 44c′, and 44d′ are provided along a second side 40e of lower surface 40a. Altemate electrical contacts 44a′, 44b′, 44c′ and 44d′ are electrically connected to electrical contacts 44a, 44b, 44c and 44d, respectively. Regardless of the orientation in which the T/R chip is inserted into the receiving depression, the T/R chip will properly contact the electrical connections as disclosed above.
An example of the circuitry that may be used in T/R chip 40 is shown in an electronic functional diagram 50 in FIG. 9. An RF input 52 is connected to third contact 44c. An RF output 54 is connected to fifth contact 44e. Switches 56 and 58 are disposed adjacent RF input 52 and RF output 54, respectively, to properly direct an RF signal through one of two electrical paths 60, 62, depending on whether an RF signal is to be sent or received. Each electrical path includes an attenuator 64, a phase shifter 66, and an amplifier 68. Other electrical components may also be included as desired. Also, the circuitry may employ common phase shifting and attenuation functions for the receive and transmit paths. The switches, attenuators, phase shifters, and amplifiers are powered by current passing through second contact 44b, and are controlled through control signals passing through first contact 44a.
As depicted in
Radiating element 92 is capacitively connected to fifth contact 44e through fourth dielectric layer 72, and therefore the thickness and dielectric constant of the fourth dielectric layer affect the performance characteristics of the microstrip antenna element.
The foregoing description has described the manufacture of a single antenna element with its associated RF, power and control circuitry. It is believed the described method of manufacture is conducive to the mass production of such antenna elements to form a single ESA using common or interconnected circuitry. An ESA so produced may include thousands or even millions of interconnected, inexpensively-produced antenna elements. In an exemplary embodiment, the conformal ESA can be configured to operate in frequencies of operation used by satellites, such as, Ka frequencies of 17.7 to 20.2 GHz and Ku frequencies of 11.7 to 12.2 GHz. Alternatively, the conformal ESA can be configured to operate at frequencies of operation such as about 4.4 GHz, or at other desired frequencies, although higher frequency applications are best suited to this invention. However, factors relating to the conductive layers such as thickness, surface roughness, and loss of the conductive layers ultimately limit the lower frequency of operation of the ESA, especially if the ESA is desired to be optically transparent. With thin conductive layers, an optically ‘transparent’ ESA may optimally be used at millimeter-wave, quasi-optical frequencies. When optical transparency is not required, the invention may be used with lower frequency ranges also with the appropriate choice of conductive layer conductivity and thickness. The required conductive layer thickness for low-loss operations is inversely proportional to the operating frequency, i.e., thicker materials are required for lower frequencies. This increase in conductive layer thickness may affect the stiffness, or pliability, of the top-level ESA assembly. Even in situations where the ESA cannot be ‘rolled up’, the invention still provides a means to create a flexible multi-layer RF substrate with one or more RF robust ground planes suitable for conformal, non-planar platform applications.
As disclosed, microstrip antenna element 94 provides relatively narrowband communication capabilities. If wideband communication capabilities are instead desired, microstrip antenna element 94 may be replaced with a known broadband antenna element design.
As previously described, the conformal ESA of the present invention may be applied to an outer surface of a display such that the display and the conformal ESA are integrally formed and deployed. If all elements of the conformal ESA are flexible and transparent (or at least substantially transparent), the conformal ESA will be virtually undetectable by a user of the display. The conformal ESA of the present invention may also be deployed independent of any display. For instance, as shown in
The invention may be varied in many ways. For example,
Previous embodiments have shown a T/R chip with angled or chamfered sides 40c, but the crystalline structure of the material from which the T/R chip is made may make it difficult to form such angled sides without cleaving of the material.
The sequence and timing at which the vias are created may also be varied as desired. For example, third via 32 and first via 22 may be formed at the same time if desired. Vias may also be created outside of receiving depression 30, with a conductive layer placed upon the first dielectric layer and etched to electrically connect the vias with contacts on the T/R chip. It is also possible to place fourth contact 44d on upper surface 40b of the T/R chip and connect the fourth contact to a conductive ground plane deposited upon first dielectric layer. Other variations are also possible and are within the scope of the invention as claimed.
Thus, it can be seen that the invention provides a communications antenna that may be used in many different applications. An advantage of the invention is that it may be deployed on an outer surface of a display, thereby eliminating the need for a separate antenna.
Another advantage is that the invention may be made using rolled manufacturing techniques similar to the techniques used in creating known LCD displays. This means that the invention may be easily produced at a fraction of the cost of previously developed, labor intensive phased array antennas.
Another advantage is, that the invention may be applied to curved surfaces, such as the outer surface of a vehicle.
While the invention has been disclosed in its preferred form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the invention includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions and/or properties disclosed herein. No single feature, function, element or property of the disclosed embodiments is essential to all of the disclosed inventions. Similarly, where the claims recite “a” or “a first” element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.
It is believed that the following claims particularly point out certain combinations and subcombinations that are directed to the disclosed inventions and are novels and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements and/or properties may be claimed through amendment of the present claims or presentation of new claims in this application. Such amended or new claims, whether they are directed to a different invention or directed to the same invention, whether different, broader, narrower or equal in scope to the original claims, are also regarded as included within the subject matter of the invention of the present disclosure.
Number | Name | Date | Kind |
---|---|---|---|
6388621 | Lynch | May 2002 | B1 |
6396449 | Osterhues et al. | May 2002 | B1 |
6483481 | Sievenpiper et al. | Nov 2002 | B1 |
6653985 | Sikina et al. | Nov 2003 | B2 |
6670921 | Sievenpiper et al. | Dec 2003 | B2 |