Detailed Description
Exemplary embodiments will now be described more fully with reference to the accompanying drawings.
RKE antennas are sometimes integrated in vehicle antenna assemblies. The inventors of the present application have recognized that existing RKE antennas may have narrow bandwidth, poor echo loss, and low passive radiation gain. Existing RKE antennas may also have frequency stability problems, for which there may be frequent center frequency changes due to vehicle motion (e.g., when the vehicle vibrates up and down, etc.).
Having recognized the above, the inventors herein have presented and disclosed exemplary embodiments of antennas (e.g., remote Keyless Entry (RKE), remote Keyless Ignition (RKI), tire Pressure Monitoring (TPM), etc.) for remote control vehicle applications. The antenna may be used in a vehicle antenna assembly such as a shark fin antenna assembly. In some exemplary embodiments disclosed herein, the RKE antenna may have one or more (but not necessarily any or all) of the following features, such as wide bandwidth, good return loss, high passive radiation gain, good frequency stability, small size, and/or no need to integrate a low noise amplifier in the RKE antenna.
In the exemplary embodiments disclosed herein, an antenna for remote control vehicle use may include a Printed Circuit Board (PCB) (generally, a substrate) and a plurality of electrical conductors (e.g., conductive traces or wires, etc.). The first and second electrical conductors may be arranged (e.g., wound, coiled, convoluted, coiled, etc.) around or within the PCB such that the first and second electrical conductors define or include first and second helical antenna elements (e.g., rectangular coils or helical coils, etc.) extending along a portion of the length or height of the PCB. The first and second helical antenna elements are intertwined, interleaved or concentric with each other. But the first and second helical antenna elements are physically and electrically spaced apart from each other and are not in electrical contact with each other. During operation of the antenna, the antenna may operate as a monopole with an inductor and capacitor load. The first and second electrical conductors may operate as or include positive and negative electrodes, respectively.
Referring now to the drawings, FIG. 1 illustrates a vehicle antenna assembly 100 embodying one or more aspects of the present disclosure. As shown in fig. 1, the vehicle antenna assembly 100 includes an antenna 104, a base or mount 108, and a radome or cover 112. The RKE antenna 104 is disposed within an interior that is collectively defined by the base 108 and the radome 12 or between the base 108 and the radome 112. The radome 112 has a shark fin shape, such that the antenna assembly 100 may also be referred to as a shark fin antenna. In an exemplary embodiment, the RKE antenna 104 may be configured for other remote control vehicle uses, such as Remote Keyless Ignition (RKI), tire Pressure Monitoring (TPM), and the like.
As shown in fig. 2 and 3, RKE antenna 104 includes a Printed Circuit Board (PCB) (generally, a substrate) 116 and a plurality of antenna elements (generally, electrical conductors). For example, the PCB116 may include an FR4 composite including woven fiberglass cloth with a fire resistant epoxy adhesive. As another example, the antenna element may include a conductive trace or wire (e.g., copper, etc.).
The plurality of antenna elements includes first and second electrical conductors 120, 124 disposed (e.g., wound, coiled, convoluted, coiled, etc.) around the PCB116 or within the PCB 116. For example, each of the first and second electrical conductors 120, 124 may be disposed along first and second opposite sides or facing opposite sides 128 of the PCB 116. Each of the first and second electrical conductors 120, 124 may be wrapped around an end or edge of the PCB116 such that each of the first and second electrical conductors 120, 124 is a single continuous electrical conductor extending along a side of the PCB116 and around the end of the PCB 116. Alternatively, portions of the first and second electrical conductors 120, 124 along one side of the PCB116 may be adjacent to corresponding portions of the first and second electrical conductors 120, 124 along an opposite side of the PCB 116. Alternatively, for example, portions of the first and second electrical conductors 120, 124 along one side of the PCB116 may electrically connect or interconnect portions of the first and second electrical conductors 120, 124 along an opposite side of the PCB116, such as by plating vias, interconnects, solder within the vias, and the like.
The first and second electrical conductors 120, 124 may respectively define or include first and second helical antenna elements (e.g., rectangular coils or helical coils, etc.) that are wound around each other, interleaved with each other, and/or concentric. The first and second electrical conductors 120 or 124 may define or include the positive and negative poles, respectively, of the RKE antenna 104.
The first and second helical antenna elements may be physically and electrically spaced apart from each other such that they are not in physical contact with each other or are not in electrical contact with each other. Instead, the first and second helical antenna elements may be coupled to each other closely, capacitively, or parasitically. In this exemplary embodiment, each of the first and second helical antenna elements includes linear or straight upwardly inclined sections or portions that are connected with a bend point (e.g., ninety degree bend, etc.) therebetween that cooperatively define twelve rectangular coils, loops, or spirals. Alternative embodiments may be configured differently, e.g., with more or less than twelve rectangular coils, loops or spirals, etc.
A plurality of antenna elements extend (e.g., linearly, vertically, etc.) from the bottom 132 of the PCB116 along the PCB116 to the top 136 of the PCT 116. During operation of the RKE antenna 104, the electrical conductors 120, 124 may operate as a monopole with an inductor and capacitor load. The first and second electrical conductors 120, 124 may operate as or include a positive electrode and a negative electrode, respectively. Furthermore, in the exemplary embodiment, electrical conductors 120, 124 are not in physical or electrical contact with each other. Instead, the electrical conductors 120, 124 are configured to be coupled to each other near, capacitively, or parasitically.
With continued reference to fig. 2 and 3, the first electrical conductor 120 includes an end 140 that extends out of the bottom 132 of the PCB 116. End 140 may serve as an output or port for RKE antenna 104, for example, for outputting a received RKE antenna signal for remotely locking or unlocking a motorized door from a location remote from the vehicle and/or without physical contact with the vehicle.
As shown in FIG. 1, the RKE antenna 104 may be coupled (e.g., soldered, etc.) to the PCB 148 (FIG. 1) such that the PCB116 of the RKE antenna 104 is generally perpendicular to the PCB 148.PCB 148 may be coupled to base 108 by mechanical fasteners 152 or the like. Additionally, RKE antenna 104 may include a protrusion 154 (fig. 4), which protrusion 154 extends downward and is interconnected within a corresponding slot or opening in PCB 148 to help position and/or couple PCB116 of RKE antenna 104 with PCB 148.
Fig. 4 also provides an example size (in millimeters (mm)) of PCB116 of RKE antenna 104. As shown, the PCB116 may have a height of about 52mm without including the downwardly extending tab 154. When including downwardly extending protrusions 154, PCB116 may have an overall height of approximately 54 mm. The PCB116 may have a width of 18mm and a thickness of 3.2 mm. These dimensions (and all other dimensions disclosed herein) are merely examples, as larger or smaller PCBs and antennas may be used in other exemplary embodiments.
Fig. 1 also shows a sealing member 156, which sealing member 156 may operate as a seal to prevent intrusion of contaminants (e.g., dust, moisture, etc.) between the vehicle mounting surface and the base 108. Additionally, the radome 112 can provide an aesthetically pleasing appearance to the antenna assembly 100, and can be configured (e.g., sized, shaped, constructed, etc.) to have an aerodynamic configuration. In the illustrated embodiment, for example, the radome 112 has an aesthetically pleasing aerodynamic shark fin configuration. However, in other exemplary embodiments, the antenna assembly may include a cover having a different configuration than that shown herein, e.g., having a configuration other than a shark fin configuration, etc. It is within the scope of the present disclosure that the radome 12 may be formed from a variety of materials, such as, for example, polymers, polyurethanes, plastic materials (e.g., polycarbonate blends, polycarbonate-acrylonitrile-butadiene-copolymer (PC/ABS) blends, etc.), glass reinforced plastic materials, synthetic resin materials, thermoplastic materials, and the like.
Fig. 5-7 provide analysis results of computer simulation models of RKE antenna 112 shown in fig. 2 and 3. The results shown in fig. 5-7 are provided for illustration purposes only and are not intended to be limiting. In alternative embodiments, the RKE antennas may be configured differently and may have different operational or performance parameters than those shown in fig. 5-7. For example, another exemplary embodiment may include RKE antennas configured to have bandwidths of 313MHz to 316 MHz. In yet another embodiment, the antenna may be configured for other remote vehicle uses other than RKE, such as remote keyless ignition, tire pressure monitoring, etc.
More specifically, FIG. 5 is a line graph showing decibel (dB) return loss versus megahertz (MHz) frequency for RKE antenna 112 shown in FIGS. 2 and 3. In general, FIG. 5 shows that RKE antenna 112 has good echo loss of-8 dB or less/better for frequencies from 430MHz to 438MHz, such as-8.7915 dB at 430MHz, -13.323dB at 433MHz, -8.1148dB at 438MHz, and so on.
Fig. 6 is a line graph of decibel isotropic (dBi) linear average gain (vertical polarization) versus megahertz (MHz) frequency for the RKE antenna shown in fig. 2 and 3 over a one meter diameter ground plane. Fig. 7 shows the minimum and maximum average linear gains for the frequencies shown in fig. 6. In general, FIGS. 6 and 7 show that RKE antenna 112 has good linear gain of greater/better than-3 dBi over the entire wide RKE frequency range or bandwidth from 432MHz to 434 MHz.
In an exemplary embodiment, the antenna disclosed herein (e.g., RKE antenna 112, etc.) may be integrated into a roof-mounted antenna assembly such that the function, style, footprint, and/or attachment scheme of the antenna may remain the same or substantially the same, and no significant changes are required regardless of the additional antenna function. For example, the vehicle antenna assembly may include a RKE antenna and one or more other different types of antennas, such as one or more AM/FM radio antennas, satellite digital audio broadcasting service (SDARS) antennas, global Navigation Satellite System (GNSS) antennas, cellular antennas, wi-Fi antennas, and so forth. In this embodiment, the RKE antenna and one or more other antennas may be co-located or mounted on a common base or mount and positioned under the same radome or housing having a shark fin configuration. The vehicle antenna assembly may be mounted or assembled on a vehicle surface, such as on a roof, trunk or hood, to help ensure that the antenna has an unobstructed view on or toward the zenith and to enable the mounting surface of the vehicle to act as a ground plane for the antenna assembly to improve signal reception. One or more other antennas may be connected (e.g., via coaxial cable, etc.) to one or more electronic devices (e.g., radio receiver, touch screen display, navigation device, cellular telephone, etc.) within the vehicle passenger cabin such that the vehicle antenna assembly is operable to transmit signals to and receive signals from the electronic devices within the vehicle.
For example, the antenna disclosed herein may be included as part of a remote keyless module (e.g., a remote keyless entry module, a remote keyless ignition module, etc.) for a vehicle (e.g., an automobile, a motorcycle, a boat, etc.). The antenna may be disposed within a housing or radome (e.g., for protecting the antenna from intrusion of debris, etc.) and coupled to the vehicle for operation. And, the mounted antenna may receive a signal of a desired frequency (e.g., from a key, trim, etc.) for initiating a desired vehicle operation (e.g., unlocking a door, initiating ignition, etc.).
The antennas disclosed herein may be configured to receive signals at one or more particular frequencies. For example, exemplary embodiments of the antenna may be configured to receive signals at a frequency of about 315 megahertz (MHz) and/or about 433MHz, etc. In other exemplary embodiments, the antenna may be configured to receive signals at one or more different frequencies within the scope of the present disclosure.
The antenna disclosed herein may be mounted on a variety of support structures. For example, the RKE antennas disclosed herein may be mounted on support structures of other mobile platforms such as buses, trains, airplanes, bicycles, motorcycles, boats, and the like. Thus, specific references herein to a motor vehicle or automobile should not be construed as limiting the scope of the disclosure to any particular type of support structure or environment.
Exemplary embodiments are provided as: this disclosure will be thorough and complete and will fully convey the scope to those skilled in the art. Numerous specific details are set forth, such as examples of specific components, devices, and methods, in order to provide a thorough understanding of embodiments of the present invention. It will be appreciated by those skilled in the art that: no specific details need to be employed; the exemplary embodiments may be embodied in many different forms; and the exemplary embodiments should not be construed as limiting the scope of the invention. In several exemplary embodiments, well-known processes, well-known device structures, and well-known techniques have not been described in detail. Furthermore, the advantages and improvements that may be realized by one or more embodiments of the present invention are provided for illustrative purposes only and are not limiting to the scope of the present invention, as the exemplary embodiments disclosed herein may provide all or none of the above advantages and improvements while remaining within the scope of the present invention.
The specific dimensions, specific materials, and/or specific shapes disclosed herein are examples in nature and are not intended to limit the scope of the invention. The particular values and ranges of values for the given parameters disclosed herein do not exclude other values and ranges of values that may be useful in one or more of the embodiments disclosed herein. Moreover, it is conceivable to: any two particular values of a particular parameter described herein may define endpoints of a range of values appropriate for the given parameter (e.g., disclosure of a first value and a second value of the given parameter may be read as meaning that any value between the first value and the second value may also be used for the given parameter). For example, if the parameter X is illustrated here as having the value a and is also illustrated as having the value Z, then it is conceivable that: the parameter X may have a range of values from about a to about Z. Similarly, it is conceivable to: the disclosure of two or more numerical ranges of parameters (whether nested, overlapping, or otherwise) includes all possible combinations of numerical ranges that may be required to use the endpoints of the disclosed ranges. For example, if the parameter X is illustrated herein as having a value in the range of 1 to 10, or 2 to 9, or 3 to 8, it is equally conceivable: the parameter X may have other numerical ranges including 1 to 9, 1 to 8, 1 to 3, 1 to 2, 2 to 10, 2 to 8, 2 to 3, 3 to 10, and 3 to 9.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," and "including" are inclusive and thus specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The steps, processes, and operations of the methods described herein are not to be construed as necessarily requiring their performance in the detailed order described or illustrated, unless the detailed order is specifically identified as an order of performance. It should also be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being "on," "engaged to," "connected to" or "coupled to" another element or layer, it can be directly on, engaged, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly engaged to," "directly connected to" or "directly coupled to" another element or layer, there may be no intervening elements or layers present. Other words used to describe relationships between elements (e.g., "between" and "directly between", "abutting" versus "directly abutting", etc.) should be interpreted in the same manner. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
The term "about" when used in numerical terms means: allowing the calculation or measurement to be slightly less accurate in terms of value (near accurate value; near or reasonably close to value; difference). For some reason, "about" as used herein means at least a modification that may result from conventional methods of measuring or using these parameters if the imprecision otherwise provided by "about" is not otherwise understood in the art in its ordinary sense. For example, the terms "substantially," "about," and "substantially" may be used herein to refer to within manufacturing tolerances (e.g., angle +/-30',0 plane +/-0.5,1 plane +/-0.25,2 plane +/-0.13, etc.). Whether or not modified by the term "about", the claims contain equivalent amounts.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. No order or sequence is implied when used herein such as "first," "second," or many other terms unless the context clearly indicates otherwise. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer arc section without departing from the teachings of the example embodiments.
Spatially relative terms, such as "inner," "outer," "underlying," "lower," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is operated, elements described as below or beneath other elements or features would then be oriented above the other elements or features. Thus, the embodiment term "below" may include both "above" and "below" orientations. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The foregoing description of the embodiments has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements of the embodiments, intended or described uses or features are not generally limited to the embodiments, but, even if not explicitly shown or described, are interchangeable where appropriate and can be used in selected embodiments. The same embodiment can be modified in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.