Multi-band circularly polarized antenna device

Abstract

A circularly polarized, multi-band, broadband antenna capable of communicating with a GPS system. The antenna may include a driven element, a first conductive parasitic element electrically connected to the driven element, a second conductive parasitic element, and a third conductive parasitic element, and a ground plane. The parasitic elements are configured with varying lengths to provide wideband operation with multiple resonant frequencies. The radiated waves have a small propagation angle and travel at least 1 to 2 miles.

Description

[0001] Cross-application of related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 849,416, filed May 17, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure generally relates to an antenna for transmitting time-correlated acoustic sensor data. In particular, but not limited thereto, the present disclosure relates to a novel antenna arrangement associated with an acoustic sensor system for remotely transmitting readings from an acoustic sensor from a pit box, typically located underground, to a remote receiver. Background Art

[0004] To alleviate the waste and expensive issues associated with detecting water leaks, the present disclosure provides a uniquely configured antenna device (e.g., in a device loosely resembling the shape of a hand, and therefore, referred to herein as a "hand antenna") for transmitting collected or recorded acoustic sensor data via signals generated by a sensor transmission unit (STU). Generally, with exemplary embodiments of the present disclosure, the antenna device is connected to a sensor transmission unit, which in turn is connected to an acoustic sensor / recorder. The acoustic sensor detects acoustic signals associated with water flow through a water pipe or other conduit and provides recorded data to the transmission unit. The transmission unit formats the sensor data into data packets containing time of day (TOD) data and location data, such as provided by a global positioning satellite (GPS). The data is then transmitted via an antenna using a radio frequency (RF) signal. The transmission unit typically transmits the formatted data to a central reading station or data collection unit (DCU), where the data is correlated with similar data from other transmission units and acoustic recorders located elsewhere on the water network. In some cases, the RF signal can be transmitted over relatively long distances, such as a mile or more. Therefore, the remote transmission unit may require a rugged antenna that can wirelessly transmit the sensor data the necessary distance with minimal data corruption or interference.

[0005] The amount of RF energy actually radiated into the airspace, compared to the amount of RF energy intended to be radiated, is a function of many factors. These factors may include the applied voltage, the amount of current flowing through the antenna, the frequency of the signal applied to the antenna, the material from which the antenna is made, the geometry of the antenna, the angle of transmission, and the materials in the relatively close surroundings of the antenna (such as within the radius of a sphere, measuring up to several wavelengths of the radio signal applied to the antenna). As the surroundings of the antenna change, the antenna's performance (i.e., the degree to which energy is radiated from it) will also tend to change accordingly.

[0006] Therefore, various factors are considered when designing and successfully deploying an integrated antenna system according to the present disclosure. Some of these conditions or factors may include: frequency of operation, transmitter output power, antenna gain, antenna polarization, antenna pattern, azimuth beamwidth, azimuth variation, government regulations for operating radio equipment, characteristic antenna impedance, maximum wave reflection coefficient, antenna geometry, antenna location, ability to achieve installation, expected service life, ability to operate in exposed environmental conditions (such as exposure to water with very little change in operating performance due to any water absorption into the antenna system), UV resistance, shock and vibration resistance, and resistance to ambient temperature variations. In addition, cost and manufacturability factors associated with the large volume of such units are considered, for example, for use in a complete system with a large number of sensor locations throughout a water transport system, with reliability and repeatability of performance. One or more of the above parameters and conditions are considered to implement the exemplary embodiments described herein and described in detail below. Summary of the Invention

[0007] According to one aspect, an antenna device for transmitting measured acoustic data is provided. The antenna device includes a substrate and a ground plane. The antenna further includes a driven element adjacent to the substrate and electrically connected to the ground plane. The driven element includes a feed point for receiving an input current signal. The antenna device also includes a first parasitic element electrically connected to the driven element via a first shorting bar. The antenna device also includes a second parasitic element longer than the first parasitic element and electrically connected to the driven element via a second shorting bar. The antenna device also includes a third parasitic element shorter than the second parasitic element and electrically connected to the second parasitic element via a third shorting bar. The antenna device also includes a fourth parasitic element electrically separated from the first parasitic element, the second parasitic element, and the third parasitic element.

[0008] In another aspect, the antenna device further includes a non-conductive first parasitic gap disposed between the first parasitic element and the driven element, a non-conductive second parasitic gap disposed between the second parasitic element and the driven element, and a non-conductive third parasitic gap disposed between the second parasitic element and the third parasitic element.

[0009] On the other hand, the electromagnetic waves radiated from the antenna device are circularly polarized.

[0010] In another aspect, the first parasitic element and the second parasitic element are positioned on either side of the driven element.

[0011] In another aspect, the first parasitic element and the second parasitic element are positioned parallel to the driven element.

[0012] In another aspect, the antenna apparatus further includes a secondary-band element, wherein the secondary-band element is an elongated conductive member extending parallel to the first parasitic element.

[0013] In another aspect, the secondary-band element is separated from the first parasitic element by a fifth parasitic gap.

[0014] In another aspect, the first parasitic element, the second parasitic element, the third parasitic element, and the fourth parasitic element each have a different length such that the antenna apparatus has a multi-resonant response to an input current signal received at the feed point.

[0015] In another aspect, the antenna apparatus is configured to have a multi-resonant response from 450 MHz to 470 MHz.

[0016] According to one aspect, a communication system is provided that includes an antenna assembly, a communication assembly, and a pit cover. The communication assembly includes a sensor transmission unit communicatively connected to an acoustic sensor and the antenna assembly. The antenna assembly is mechanically coupled to the pit cover and positioned between the pit cover and a pipe. The pit cover is configured to provide a seal against a top portion of a valve chamber within the pipe. The acoustic sensor is physically coupled to a valve stem within the valve chamber.

[0017] In another aspect, the communication assembly is configured to transmit data collected by the sensor to a remote data collection unit via the antenna assembly.

[0018] In another aspect, an antenna device includes a substrate, a ground plane, and a driven element adjacent to the substrate and electrically connected to the ground plane. The driven element includes a feed point for receiving an input current signal. The antenna device also includes a first parasitic element electrically connected to the driven element via a first shorting bar, and a second parasitic element longer than the first parasitic element and electrically connected to the driven element via a second shorting bar. The antenna device also includes a third parasitic element shorter than the second parasitic element and electrically connected to the second parasitic element via a third shorting bar, and a fourth parasitic element electrically isolated from the first, second, and third parasitic elements.

[0019] In another aspect, an antenna assembly includes a first non-conductive parasitic gap disposed between a first parasitic element and a driven element, a second non-conductive parasitic gap disposed between a second parasitic element and the driven element, and a third non-conductive parasitic gap disposed between the second parasitic element and a third parasitic element.

[0020] In another aspect, the conduit is in electrical communication with a ground plane of the antenna assembly and is configured to produce a low radiation angle from the antenna assembly.

[0021] On the other hand, the electromagnetic waves radiated from the antenna device are circularly polarized.

[0022] In another aspect, the first and second parasitic elements are positioned on either side of the driven element in a parallel orientation.

[0023] In one aspect, an antenna assembly is provided that includes a ground plane, a substrate, and a driven element adjacent to the substrate and electrically connected to the ground plane. The driven element includes a feed point for receiving an input current signal. The substrate has an antenna arrangement arranged thereon and includes a first parasitic element electrically connected to the driven element via a first shorting bar. The antenna arrangement also includes a second parasitic element that is longer than the first parasitic element and electrically connected to the driven element via a second shorting bar. The antenna arrangement also includes a third parasitic element that is shorter than the second parasitic element and electrically connected to the second parasitic element via a third shorting bar, and a fourth parasitic element that is electrically separated from the first parasitic element, the second parasitic element, and the third parasitic element. The first parasitic element, the second parasitic element, the third parasitic element, and the fourth parasitic element each have a different length so that the antenna arrangement has a multi-resonant response to the input current signal received at the feed point.

[0024] In one aspect, the antenna arrangement is configured to have a multi-resonant response from 450 MHz to 470 MHz.

[0025] In one aspect, an antenna device includes a first non-conductive parasitic gap disposed between a first parasitic element and a driven element, and a second non-conductive parasitic gap disposed between a second parasitic element and the driven element. The antenna device also includes a third non-conductive parasitic gap disposed between the second parasitic element and a third parasitic element.

[0026] In one aspect, the electromagnetic waves radiated from the antenna arrangement are circularly polarized.

[0027] Antennas according to one or more aspects of the disclosed embodiments radiate at low horizontal angles within valve manifold piping constructed of metallic or non-metallic materials. According to further embodiments, the antennas are multi-band and ultra-wideband, operating within the FCC-licensed frequency range of 450 MHz to 470 MHz. According to these and other embodiments, the antennas operate with GPS signals to provide relevant time and location data.

[0028] According to a further aspect, the exemplary antenna is IP67 compliant (e.g., the antenna is protected from dust and protected from immersion in water at a depth of between 15 cm and 1.0 meter for at least 30 minutes). Furthermore, the antenna according to the exemplary embodiment can operate in temperatures from -40°C to +80°C and can radiate at least 2 miles. According to another aspect of the exemplary embodiment, the antenna has a diameter of approximately 5.75 inches and can be mounted below and attached to a valve manifold cover in a water distribution network.

[0029] Other objects and features are either explicitly disclosed or will become apparent to those of ordinary skill in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a system diagram illustrating components of an exemplary overall leak detection system deploying antenna arrangements according to one or more aspects of the present disclosure;

[0031] Figure 2 is a diagram illustrating exemplary communication components according to one or more aspects of the present disclosure;

[0032] Figure 3 is a cross-sectional view of a pit cover in which an antenna apparatus according to one or more aspects of the present disclosure is deployed;

[0033] Figure 4A and Figure 4B are top and bottom views of an antenna device according to one or more embodiments of the present disclosure;

[0034] Figure 5 is a top view of an antenna pattern according to one or more exemplary embodiments, illustrating representative sizes for various antenna pattern elements.

[0035] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0036] Figure 1 1 is a system diagram illustrating an exemplary environment in which antennas according to one or more embodiments may be deployed. As shown, system 100 includes a communication assembly 101, which includes a sensor transmission unit (STU) 105 communicatively coupled to an acoustic sensor / recorder 110 and a pit lid / antenna 115. Pit lid / antenna 115 includes an antenna (not shown), which will be described in greater detail below, and provides a seal at the top of a valve chamber 120. According to the exemplary embodiment shown, communication assembly 101 is deployed within valve chamber 120, which in turn is coupled to a water pipe 125. Acoustic sensor 110 is magnetically attached to a valve stem 121 within valve chamber 120.

[0037] In one embodiment, the pit cover / antenna 115 is also configured to receive signals from one or more global positioning system satellites. The signals can be processed by the communication component 101 and can provide location, date and time information to the system.

[0038] A data collection unit (DCU) 130 (which is located one or more miles away from the valve chamber 120) initiates the data collection process by sending an RF signal to the STU 105 at a predetermined time. For example, the data collection process may be initiated in the early morning hours when ambient noise in the area surrounding the valve chamber 120 and, therefore, the pit cover / antenna 115, is minimal. Upon receiving a data collection request from the DCU 130, the STU 105 transmits the acoustic data collected by the acoustic sensor 110 to the DCU 130 via the RF signal from the antenna. The data from the STU 105 is then correlated with other such data from other STUs (e.g., in the water distribution network) and provided to the end user 140 via the network control computer (NCC) 145 for analysis and processing.

[0039] The STU 105 may format data into data packets, such as sensor data received from the acoustic sensor 110. In addition to the sensor data, the data packets may also include time of day (TOD) data and location data, which may be provided by GPS satellites.

[0040] Figure 2 Yes Figure 1 Detailed schematic diagram of a more detailed view of various exemplary components of the communication assembly 101 of the STU 105 is shown. As shown, an acoustic sensor 110 is attached to the top of the valve stem 121 of the valve 122, which can also collect and record data at specific intervals for a predetermined length of time. In an exemplary embodiment, the valve 122 controls the flow of water through the water pipe 125. A data cable 140 is connected between the STU 105 and the acoustic sensor 110 and provides a communication path for data and commands to flow between the two units. An antenna cable 150 is connected between the STU 105 and an antenna 160 located within the pit cover 115. The pit cover 115 is made of any suitable material, including non-metallic materials (such as plastic) as well as metallic materials (such as cast iron or steel).

[0041] Figure 3 is a cross-sectional view of an exemplary pit cover or valve cover 300 according to at least one embodiment. As shown, the pipe 310 includes an upper portion having an outer diameter and an inner diameter. The pipe 310 is made of steel, cast iron, PVC, or other suitable material to prevent water or other foreign materials from entering the interior cavity 315. In addition, according to one embodiment, the pipe 310 encloses the valve chamber (e.g., Figure 1 310 ), wherein a water valve (not shown) is located at one end of the pipe 310, and a pit cover 320 is disposed at the opposite end of the pipe 310. In the illustrated embodiment, the pit cover 320 is made of plastic or other material that does not reflect RF signals. The pit cover 320 provides a water-tight seal for the chamber 315 so that water accumulated on top of the pit cover 320 does not penetrate the pit cover and enter the chamber 315.

[0042] Further references Figure 3 , the antenna assembly 330 is located directly below the pit cover 320. Thus, the antenna assembly 330 is arranged below the top of the pipe 310 at a distance that is at least equal to the thickness of the pit cover 320 and is protected from water and other contaminants present outside the chamber 315. The top surface of the antenna assembly 330 includes an antenna pattern 340, and the lower surface includes a ground plane, both of which will be described in more detail below. The antenna pattern 340 and the ground plane 350 are separated by a standoff 355. The antenna feed point 360 connects the antenna pattern layer 340 and the ground plane 350 to the top portion of the data connector 370. When the antenna assembly 330 is deployed in a water leak detection system (such as Figure 1 When the water leak detection system shown in FIG. 1 is used, the bottom portion of the data connector 370 is communicatively connected to the antenna cable (eg, Figure 1 Antenna cable 150 in).

[0043] The antenna assembly 330 can be configured to be resistant to water and / or other penetrations. For example, the antenna assembly 330 can be IP67 compliant (e.g., the antenna assembly 330 is protected from dust and is protected from immersion in water at a depth of between 15 cm and 10.0 meters for at least 30 minutes). In addition, the antenna assembly 330 can be configured to operate in temperatures from -40°C to +80°C and can radiate at least 2 miles. In one embodiment, the antenna assembly is approximately 5.75 inches in diameter and can be mounted below and attached to a valve block cover (such as the pit cover 115 described above) in a water distribution network.

[0044] Figure 4A is an isometric view of the top side of an antenna device 400 according to at least one embodiment of the present disclosure. For example, the antenna device 400 may be deployed as Figure 3 The antenna device 330 in FIG. Figure 4A As shown, the top side of the antenna device 400 includes an antenna pattern 410, which can be made of any suitable radiating material (such as copper, etc.) and can be printed, etched, or formed by some other technique. As shown, the antenna pattern 410 includes a feed point 420 located near the center of the circular antenna pattern 410. The feed point 420 is electrically connected to the driving element 425 and is further electrically connected to a data source or signal source, such as Figure 3 The data connector 370 is provided on the antenna pattern 410. The driven element 425 is an elongated rectangular conductive element positioned approximately in the center of the antenna pattern 410. The first conductive parasitic element 430 and the second conductive parasitic element 440 are located on opposite sides of the driven element 425 and extend parallel to the driven element 425.

[0045] A first parasitic gap 435 and a first parasitic slot 436 separate a majority of driven element 425 from a first parasitic element 430, which extends parallel to but is shorter than driven element 425. Similarly, a second parasitic gap 445 and a second parasitic slot 446 separate a majority of driven element 425 from a second parasitic element 440, which is also parallel to and shorter than driven element 425. In reality, however, the entire length of driven element 425 is separated from first parasitic element 430 by a relatively thin, electrically conductive first shorting bar 437, which is electrically connected between driven element 425 and first parasitic element 430 and defines a first parasitic gap 435 adjacent to one side thereof and a first parasitic slot 436 on a second side thereof. Similarly, but with a relatively thin conductive second shorting bar 447 electrically connected between the driven element 425 and the second parasitic element 440 and defining a second parasitic gap 445 adjacent one side thereof and a second parasitic slot 446 on a second side thereof, the entire length of the driven element 425 is separated from the second parasitic element 440.

[0046] Conductive third parasitic element 450 is located on the opposite side of second parasitic element 440, i.e., on the side opposite driven element 425. Third parasitic element 450 extends parallel to, but is shorter than, second parasitic element 440. Third shorting bar 457 electrically connects second parasitic element 440 and third parasitic element 450 and defines a non-conductive third parasitic gap 455 and a third parasitic slot 456 on either side thereof.

[0047] Secondary-band element 460 is an elongated conductive member extending parallel to first parasitic element 430 and separated from first parasitic element 430 by a fifth parasitic gap 465. A fourth shorting bar 467 provides a thin electrical connection between first parasitic element 430 and secondary-band element 460. A fourth conductive parasitic element 470, electrically isolated from the other conductive parasitic elements and driven element 425, is positioned adjacent to a narrow side of first parasitic element 430 and separated therefrom by a fourth parasitic gap 475. All conductive elements of antenna pattern 410 are formed on top of substrate 480 and can be formed by processes such as etching or printing with conductive ink. Copper strips attached to the substrate can also be used to form the conductive parasitic elements and driven elements. Substrate 480 can be a dielectric substrate. The material of substrate 480 can be a printed circuit board (PCB) made of fiberglass-reinforced epoxy (FR4), bismaleimide-triazine (BT) resin, sheet molding compound (SMC), or any other non-conductive or insulating material. In one embodiment, substrate 480 is frequency stable within a desired output frequency range (eg, 450 MHz-470 MHz).

[0048] according to Figure 4AIn one aspect of the illustrated embodiment, the parasitic elements each have a different length, which results in a multi-resonant response to the input current signal received at the feed point 420. For example, for a Figure 5 The parasitic elements of different lengths are shown to exhibit multiple resonances that allow for minimum return loss over the FCC-approved frequency range of 450 MHz to 470 MHz. However, in some embodiments, the multiple resonance frequency can be as low as 430 MHz. The multiple resonances are close in frequency, which results in a wide bandwidth aggregate response.

[0049] refer to Figure 4B As shown, a plurality of standoff elements 485 are attached to the underside of the substrate 480, which separate the antenna assembly 410 from the ground plane 490. Ground plane connector points 495 provide electrical connections between the antenna assembly 310 and the ground plane 490 at each base, respectively. Feedthrough connectors 482 are attached to the underside of the ground plane 490 and connect the feed point 420 on the antenna assembly 410 to the drive signal, e.g. Figure 2 A connection is provided between the antenna cables 150.

[0050] Figure 5 is a plan view of an antenna device according to one or more embodiments of the present disclosure. More specifically, Figure 5 The above reference Figure 4A The dimensions of the antenna elements of the antenna device described are as follows. For example, as shown, the driven element 425 is centered on the circular substrate and has a length relative to the drive member or feed point 420 that is approximately equal to 1.9 inches and a width of approximately 0.5 inches, that is, 0.25 inches on either side of the center. In addition, each parasitic element, gap, and slot has a width of approximately 0.50 inches and has a specific length that is indicative of the radiation characteristics of the antenna (described further below). In addition, the center of each conductive parasitic element is 1.0 or 2.0 inches from the center of the driven element 425. For example, the second parasitic element and the third parasitic element are positioned at 1.0 and 2.0 inches, respectively, on one side of the driven element 425, and the first parasitic element and the secondary band element are positioned at 1.0 and 2.0 inches, respectively, on the opposite side of the driven element 425. Further dimensions and relative positions of each antenna element according to this embodiment of the present disclosure are as follows: Figure 5 This is evident in the review.

[0051] Figure 4A The shorting bars (e.g., 437, 447, 457, and 467) shown increase the overall bandwidth of the antenna device. The respective lengths of the conductive elements (e.g., 425, 430, 440, 450, and 460) help indicate overlapping resonances to achieve the overall desired wide bandwidth. According to the illustrated embodiment, the overall bandwidth is large enough to accommodate manufacturing variability and material instabilities of the antenna device.

[0052] According to one or more further exemplary embodiments, the connection between the conductive portion of the antenna pattern and the ground plane is centered between the first parasitic element (430) and the second parasitic element (440). The open parasitic slots (e.g., 436, 446, 456) affect the overall tuning and bandwidth. The fourth parasitic element (470) affects the radiation pattern, for example, providing circular polarization of the radiated signal, and also affects the overall tuning. In some embodiments, the polarization of the conductive elements (e.g., 425, 430, 440, 450, and 460) affects the radiation pattern to produce circular polarization of the radiated signal. For example, the conductive elements can be a combination of horizontal polarization and vertical polarization to produce circular polarization of the radiated signal. The combination of elements, including the ground plane and the conduit (e.g., Figure 3 310) in size, helps the antenna emit a low radiation angle and pattern. For example, a pipe (such as Figure 3 310 in) may affect the operation of the antenna, such as by providing a larger effective ground plane for the antenna. Size, material type, ground depth, etc. may affect the effect of the pipeline on the antenna. In one embodiment, the radiation pattern emitted from the antenna is an orthogonal polarization radiation pattern that provides strong above-ground radiation in all directions. Each of these parameters (e.g., the number, size, and position of elements) can also be adjusted for other frequencies. In some embodiments, the antenna can be configured to transmit radio frequency (RF) signals over relatively long distances (e.g., more than a mile).

[0053] Pit covers (e.g. Figure 1 and Figure 2 115) has a loading effect on the antenna. Therefore, in the configurations provided in the various disclosed exemplary embodiments, due to this loading effect, the antenna pattern is tuned to above or above the desired frequency range (450 MHz to 470 MHz). Furthermore, this design can be adjusted for multiple frequency bands and bandwidths.

[0054] The Abstract and Summary are provided to help the reader quickly ascertain the nature of the technical disclosure. They are submitted with the understanding that they will not be used to interpret or limit the scope or meaning of the claims. This Summary is provided to introduce a selection of concepts in a simplified form that are further described in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the claimed subject matter.

[0055] When introducing elements of aspects of the invention or embodiments thereof, the articles "a," "an," "the," and "said" are intended to mean that there are one or more elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0056] In view of the above, it will be seen that the several advantages of various aspects of the invention are achieved and other advantageous results attained.

[0057] Not all components depicted in the illustrations or descriptions are required. Furthermore, some embodiments and examples may include additional components. The arrangement and types of components may be varied without departing from the spirit or scope of the claims set forth herein. Additional, different, or fewer components may be provided, and components may be combined. Alternatively or additionally, a component may be implemented by multiple components.

[0058] The above description has been given by way of example and not limitation to illustrate various aspects of the present invention. This description enables those skilled in the art to make and use aspects of the present invention, and describes several embodiments, modifications, variations, substitutions, and uses of aspects of the present invention. Furthermore, it should be understood that aspects of the present invention are not limited in their application to the configuration details and arrangements of components set forth in the specification or shown in the accompanying drawings. Various aspects of the present invention can have other embodiments and be practiced or executed in a variety of ways. Furthermore, it should be understood that the wording and terminology used herein are for descriptive purposes and should not be considered as limiting.

Claims

1. An antenna device, comprising: substrate; Ground plane; a driving element adjacent to the substrate and electrically connected to the ground plane, the driving element including a feed point for receiving an input current signal; a first parasitic element electrically connected to the driving element via a first shorting bar; a second parasitic element longer than the first parasitic element and electrically connected to the driving element via a second shorting bar; a third parasitic element shorter than the second parasitic element and electrically connected to the second parasitic element via a third shorting bar; as well as a fourth parasitic element electrically separated from the first parasitic element, the second parasitic element, and the third parasitic element, Wherein, the electromagnetic waves radiated from the antenna device are circularly polarized.

2. The antenna device according to claim 1, further comprising: a non-conductive first parasitic gap disposed between the first parasitic element and the driven element; a non-conductive second parasitic gap disposed between the second parasitic element and the driven element; as well as A non-conductive third parasitic gap is disposed between the second parasitic element and the third parasitic element.

3. The antenna device according to claim 1, wherein The first parasitic element and the second parasitic element are positioned on either side of the driven element. The antenna device according to claim 3 , wherein: The first parasitic element and the second parasitic element are positioned parallel to the driven element.

5. The antenna device according to claim 1, further comprising a secondary band element, wherein The secondary-band element is an elongated conductive member extending parallel to the first parasitic element. The antenna device according to claim 5 , wherein: The secondary band element is separated from the first parasitic element by a fifth parasitic gap.

7. The antenna device according to claim 1, wherein The first parasitic element, the second parasitic element, the third parasitic element, and the fourth parasitic element each have a different length so that the antenna device has a multi-resonant response to the input current signal received at the feed point.

8. The antenna device according to claim 7, wherein: The antenna arrangement is configured to have a multi-resonant response from 450 MHz to 470 MHz.

9. An antenna assembly comprising: Ground plane; substrate; as well as a driving element adjacent to the substrate and electrically connected to the ground plane, the driving element including a feed point for receiving an input current signal; The substrate has an antenna device arranged thereon, and the antenna device includes: a first parasitic element electrically connected to the driving element via a first shorting bar; a second parasitic element longer than the first parasitic element and electrically connected to the driving element via a second shorting bar; a third parasitic element that is shorter than the second parasitic element and electrically connected to the second parasitic element via a third shorting bar; and a fourth parasitic element electrically separated from the first parasitic element, the second parasitic element, and the third parasitic element; wherein the first parasitic element, the second parasitic element, the third parasitic element, and the fourth parasitic element each have a different length so that the antenna device has a multi-resonant response to an input current signal received at the feed point, Wherein, the electromagnetic waves radiated from the antenna device are circularly polarized.

10. The antenna assembly according to claim 9, wherein: The antenna arrangement is configured to have a multi-resonant response from 450 MHz to 470 MHz.

11. The antenna assembly according to claim 9, wherein: The antenna device further comprises: a non-conductive first parasitic gap disposed between the first parasitic element and the driven element; a non-conductive second parasitic gap disposed between the second parasitic element and the driven element; and A non-conductive third parasitic gap is disposed between the second parasitic element and the third parasitic element.

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