1. Field of the Invention:
The present invention generally relates to automobile antennas.
2. Description of the Known Technology:
Plastic materials, such as polycarbonate (PC) and polymethyl methyacrylate (PMMA), are currently being used in the manufacturing of numerous automotive parts and components, such as B-pillars, headlamps, and sunroofs. Automotive window modules represent an emerging application for these plastic materials because of various advantages in the areas of styling/design, weight savings, and safety/security. More specifically, plastic materials offer the automotive manufacturer the ability to reduce the complexity of the window assembly through the integration of functional components into the molded plastic module as well as to distinguish their vehicle from a competitor's vehicle by increasing overall design and shape complexity. The use of light weight plastic window modules may facilitate both a lower center of gravity for the vehicle and improved fuel economy. Additionally, plastic window modules increase the overall safety of a vehicle by enhancing the retention of occupants during a rollover accident.
Until recently, telecommunication systems present in an automobile were limited to a few systems, mainly the analog radio reception (AM/FM bands). The most common solution for these systems is a typical whip antenna mounted on the car roof or body. The current tendency in the automotive sector is to reduce the aesthetic and aerodynamic impact due to these antennas by lowering their profiles and embedding them in the vehicle structure. Furthermore, a major integration of several telecommunication services into a single antenna would help to reduce the manufacturing costs or the damages due to vandalism and car wash equipments.
Therefore, it is desired to provide an antenna system that features minimal aesthetic or aerodynamic impact, protection from vandalism and is cost effective to manufacture.
In overcoming the drawbacks and limitations of the known art, the present invention provides an automobile having a window assembly with an antenna embedded within the window assembly. The window assembly includes a plastic substrate having a top side and a bottom side. The plastic substrate may be made of a thermoplastic resin including, but not limited to, polycarbonate resins, acrylic resins, polyarylate resins, polyester resins, and polysulfone resins, as well as copolymers and and any combination thereof. Preferably, the plastic substrate is transparent.
On the exterior side of the plastic substrate is one or more protective layers including a weathering layer. The weathering layer provides high weatherablity and long term ultraviolet (UV) protection. Covering the weathering layer may be an abrasion layer. The abrasion layer provides a “glass-like” abrasion resistance.
An antenna trace may be located at numerous locations within the window assembly. Preferably, the antenna trace is made of a silver pigmented ink. However, the antenna trace may be made of any material suitable for the reception of wireless signals such as metallic pigmented inks, conductive films, or conductive polymers.
Further objects, features and advantages of this invention will become readily apparent to persons skilled in the art after a review of the following description, with reference to the drawings and claims that are appended to and form a part of this specification.
Referring to
As stated previously, the window assembly 12 has the antenna 16 embedded within. The antenna 16 is capable of receiving any number of wireless signals including, but not limited to AM, FM, satellite radio (such as XM™ and Sirius™), GSM, CDMA, IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11x, HomeRF™ and Bluetooth™. Generally, the antenna 16 is a fractal shaped antenna; however, any suitable shaped antenna may be used.
An interface 18 is connected to the antenna 16. The interface functions to connect a device capable of processing wireless signals, such as a radio receiver, to the antenna 16. For example, if a radio receiver (not shown) is connected to the interface 18, the radio receiver will be capable of receiving wireless signals, such as AM and FM, from the antenna 16 via the interface 18.
Although this description describes using the window assembly 14 as a side window of the automobile 10, the invention is equally applicable to other areas of the automobile 10. For example, the window assembly 14 may be appropriately located and dimensioned to be used as a moon/sun roof, driver side window, a passenger side window, rear windows, a front windshield and/or any other windows the automobile 10 may have.
Referring to
Located above the top side 21 of the plastic substrate 20 an antenna trace 22. The antenna trace 22 is a cross section portion of the antenna 16 shown in
Above the antenna trace 22 is a weathering layer 24. The weathering layer 24 may be constructed of two layers: a primer layer 26 and a hard-coat layer 28. One example of a primer layer 26 is an acrylic primer, such as SHP401 from General Electric Silicones of Wilton, Connecticut, or SHP9X from Exatec L.L.C. of Wixom, Mich. The hard-coat layer 28 is generally a silicone hard-coat such as AS4000 from General Electric Silicones or SHX from Exatec, L.L.C. However, other hard-coat compositions, such as polyurethanes, either applied on top of a primer layer or directly to the antenna and plastic substrate may be utilized.
The weathering layer 24 provides high weatherablity and long term UV protection. Further, the weathering layer 24 may also include a material having lonomer chemistry or similar material. Moreover, in another embodiment of the present invention silicon/nanoparticles may be blended into the material of the weathering layer 24 or a silioxane copolymer is formed into the weathering layer 24 by polymerization. The weathering layer may be applied by any technique known to those skilled in the art including but not limited to spray coating, flow coating, dip coating, spin coating, and curtain coating.
Covering the weathering layer 24 is an abrasion layer 30. The abrasion layer provides “glass-like” abrasion resistance to the window assembly 14. The plasma layer 30 may be a SiOxCyHz film deposited by plasma enhanced chemical vapor deposition (PECVD). The abrasion layer 30 may be a multilayered system with each layer comprising a slightly different composition. The abrasion layer may be applied by any technique known to those skilled in the art including but not limited to plasma enhanced chemical vapor deposition, ion assisted plasma deposition, magnetron sputtering, electron beam evaporation, and ion beam sputtering.
Referring to
Referring to
Referring to
Referring to
As a person skilled in the art will readily appreciate, the above description is meant as an illustration of implementation of the principles this invention. This description is not intended to limit the scope or application of this invention in that the invention is susceptible to modification, variation and change, without departing from spirit of this invention, as defined in the following claims.