Dual-band omnidirectional antenna

Abstract

Provided are embodiments of a system and method for operating an omnidirectional antenna. The embodiments include operating a first antenna that includes: a first input configured to receive an input signal; a plurality of sub-arrays configured for transmitting and receiving signals; and a ground plane of the first antenna. The embodiments further include: operating a second antenna coupled to the first antenna, the second antenna including a second input configured to receive an input signal, a plurality of arms configured for transmitting and receiving signals, a ground plane of the second antenna; and coupling the ground plane of the first antenna and the ground plane of the second antenna.

Description

Technical Field

[0001] The exemplary embodiments relate to the field of wireless communication, and more particularly to systems and methods for operating a dual-band omnidirectional antenna. Background Art

[0002] Directional antennas radiate energy in a specific general direction, while omnidirectional antennas radiate energy in all directions perpendicular to the azimuthal direction in a plane. These antennas can be used in various applications, including Global Positioning System (GPS), wireless communication, radio broadcasting, etc. The antenna type can be optimized for various applications. Relative operating characteristics and functionality may be required to expand the capabilities of the antenna system. Summary of the Invention

[0003] According to an embodiment, an antenna system is provided. The system includes a first antenna, which includes: a first input configured to receive an input signal; a plurality of sub-arrays configured for transmitting and receiving signals; and a ground plane of the first antenna. The system further includes a second antenna coupled to the first antenna, where the second antenna includes: a second input configured to receive an input signal; a plurality of arms configured for transmitting and receiving signals; and a ground plane of the second antenna, where the ground plane of the first antenna is coupled to the ground plane of the second antenna.

[0004] In addition to one or more of the features described herein, or alternatively, further embodiments include: the first antenna as an omnidirectional antenna array; and the second antenna as a multi-arm folded monopole antenna, where at least one of the plurality of arms is connected to the ground plane of at least one of the sub-arrays of the first antenna.

[0005] In addition to one or more of the features described herein, or alternatively, further embodiments include a plurality of sub-arrays, which include a top layer and a bottom layer, where the bottom layer includes the ground plane of the first antenna, and the top layer includes a plurality of radiation patches.

[0006] In addition to one or more of the features described herein, or alternatively, further embodiments include a common input.

[0007] In addition to one or more of the features described herein, or alternatively, further embodiments include at least one of the plurality of sub-arrays, which includes a low-pass filter connected to one of the plurality of radiation patches.

[0008] In addition to one or more of the features described herein, or alternatively, further embodiments include a low-pass filter disposed between one of the plurality of arms of the second antenna and one of the plurality of radiation patches.

[0009] In addition to one or more of the features described herein, or alternatively, additional embodiments include a radiation patch connected to one of a plurality of arms located on top of a sub-array.

[0010] In addition to one or more of the features described herein, or alternatively, additional embodiments include a first antenna and a second antenna operating in different frequency bands.

[0011] In addition to one or more of the features described herein, or alternatively, additional embodiments include a first antenna operating in the microwave band and a second antenna operating in the ultra-high frequency band.

[0012] In addition to one or more of the features described herein, or alternatively, additional embodiments include a plurality of sub-arrays of a first antenna arranged in a circular layout.

[0013] According to another embodiment, a method of operating an antenna system is provided.

[0014] The method includes operating a first antenna that includes: a first input configured to receive an input signal; a plurality of sub-arrays configured to transmit and receive signals; and a ground plane of the first antenna. The method further includes: operating a second antenna coupled to the first antenna, the second antenna including a second input configured to receive an input signal, a plurality of arms configured to transmit and receive signals, a ground plane of the second antenna; and coupling the ground plane of the first antenna and the ground plane of the second antenna.

[0015] In addition to one or more of the features described herein, or alternatively, additional embodiments include: a first antenna as an omnidirectional antenna array; and a second antenna as a multi-arm folded monopole antenna.

[0016] In addition to one or more of the features described herein, or alternatively, additional embodiments include connecting at least one of a plurality of arms to a ground plane of a first antenna of at least one of a plurality of sub-arrays.

[0017] In addition to one or more of the features described herein, or alternatively, additional embodiments include a plurality of sub-arrays including a top layer and a bottom layer, wherein the bottom layer includes a ground plane of a first antenna and the top layer includes a plurality of radiation patches.

[0018] In addition to one or more of the features described herein, or alternatively, additional embodiments include: receiving an input, wherein the first input and the second input are a common input; filtering the received input, wherein the input is filtered using a low-pass filter, wherein the low-pass filter is positioned in at least one of a plurality of microwave sub-arrays, and wherein the low-pass filter is connected to one of a plurality of radiation patches.

[0019] In addition to one or more of the features described herein, or alternatively, additional embodiments include a low-pass filter disposed between one of the plurality of arms of the second antenna and one of the plurality of radiating patches.

[0020] In addition to one or more of the features described herein, or alternatively, additional embodiments include a radiating patch connected to one of the plurality of arms and located on top of the subarray.

[0021] In addition to one or more of the features described herein, or alternatively, additional embodiments include a first antenna and a second antenna operating in different frequency bands.

[0022] In addition to one or more of the features described herein, or alternatively, additional embodiments include that operating the first antenna includes operating in the microwave and millimeter (mm) wave bands, and operating the second antenna includes operating in the ultra-high frequency band or the microwave band.

[0023] In addition to one or more of the features described herein, or alternatively, additional embodiments include arranging a plurality of subarrays of the first antenna in a circular arrangement.

[0024] The above features and elements can be combined non-exclusively in various combinations, unless otherwise expressly indicated. From the following description and the drawings, these features and elements and their operation will become more apparent. However, it should be understood that the following description and the drawings are intended to be illustrative and explanatory in nature rather than restrictive. Description of the Drawings

[0025] The following description should in no way be construed as limiting. Referring to the drawings, like elements are numbered alike:

[0026] Figure 1 A system integrating an omnidirectional antenna array and a multi-arm folded monopole is depicted according to one or more embodiments;

[0027] Figure 2 Another system integrating an omnidirectional antenna array and a multi-arm folded monopole with a common input is depicted according to one or more embodiments;

[0028] Figure 3 A flowchart of a method of operating an antenna system is depicted according to one or more embodiments;

[0029] Figure 4A and Figure 4B The antenna characteristics of a subarray of an antenna system are depicted according to one or more embodiments;

[0030] Figure 5A 、Figure 5B and Figure 5C depicts the antenna characteristics of a multi - arm folded monopole of an antenna system according to one or more embodiments; and

[0031] Figure 6 depicts a graph representing the input impedance of a monopole according to one or more embodiments. DETAILED DESCRIPTION

[0032] In today's environment, various antennas are used for various commercial and residential applications. The applications can include radar systems, communication systems (5G), WiFi - connected routers. Antennas can be selected and configured to operate in various frequency bands and powers. Antennas for radar sensor applications and communication typically occupy a lot of space, especially when they are processed and operated separately.

[0033] Antennas can be designed to operate as directional or omnidirectional antennas. Different antenna types can be combined to expand the capabilities of a single antenna or system. However, the proximity of multiple antennas to each other can cause obstruction or interference, which actually limits the functional parameters of each antenna or antenna system. During the design process, antenna subsystems (stand - alone antennas) are usually designed separately, and only at the integration stage are the undesired phenomena of reduced functionality observed. It may be necessary to optimally and effectively combine multiple antennas into a single antenna system while maintaining the proper functionality of each antenna system.

[0034] The techniques of the embodiments described herein combine an omnidirectional antenna including a cylindrical antenna array and a multi - arm folded monopole antenna array. The utilization of the integrated antenna system allows for reduced occupied space in the sensor. The configurations of the embodiments described herein also ensure a significant reduction in the mutual obstruction between antennas, thus allowing for undistorted operation.

[0035] Figure 1 Depicts a dual - antenna system 100 according to one or more embodiments. The antenna system 100 combines a monopole antenna 102 and an omnidirectional antenna array 104 including a plurality of microwave sub - arrays 124. In a non - limiting example, the monopole antenna 102 is a multi - arm folded monopole antenna, which has a communication input 106 and four arms 108. The arms 108 of the monopole are connected to the ground plane of the microwave sub - arrays of the omnidirectional antenna array 104. The monopole antenna 102 can be configured for communication, and the operating range of the monopole antenna 102 can include, but is not limited to, the ultra - high - frequency (UHF) band (e.g., at 433 MHz, 867 MHz, 2.4 GHz, etc.).

[0036] The omnidirectional antenna array 104 can include one or more microwave sub-arrays. In a non-limiting example, the microwave sub-arrays of the omnidirectional antenna array 104 are positioned in a cylindrical arrangement. Each of the microwave sub-arrays in the microwave sub-array can be positioned separately at various degrees. In a non-limiting example, if four sub-arrays are used, the microwave sub-arrays can be offset by 90°. In another example, if six microwave sub-arrays are used, they can be offset by 60°. Although Figure 1 shows four microwave sub-arrays, it should be understood that any number of microwave sub-arrays can be used in the antenna system 100. Each of the microwave sub-arrays in the microwave sub-array can include an input 110, which is independent of the communication input 106 of the monopole antenna array 102. Additionally, each of the microwave sub-arrays in the microwave sub-array can include a plurality of radiating microstrip patch elements 116. Although Figure 1 shows four radiating microstrip patch elements 116, it should be understood that any number of radiating microstrip patch elements 116 can be incorporated into each microwave sub-array.

[0037] As Figure 1 shown, each of the microwave arrays in the microwave array extends upward from the ground plane 118, and each of the microwave sub-arrays in the microwave sub-array includes a top layer 112 and a bottom layer 114. The top layer 112 is a substrate on which the radiating microstrip patch elements 116 are provided. The bottom layer of the microwave sub-array serves as the ground plane 114.

[0038] A portion of the microwave array serves as part of the multi-arm folded monopole 102. In particular, the ground plane 114 of the microwave sub-array and the ground plane 118 of the monopole 102 are connected at the interface 122 as shown. Each of the arms 108 of the monopole 102 is connected to the ground plane 114 of the microwave sub-array at the interface 120 as shown. This reduces the size and mutual distortion of the entire antenna system 100. The multi-arm folded monopole 102 provides appropriate input impedance and better efficiency. The architecture of the system 100 enables additional electronic devices to be positioned within the integrated antenna system.

[0039] Figure 1 Also shown in is a processor 130, which is configured to control the antenna system 100. The processor 130 can be operatively coupled to the system 100. In some embodiments, the processor 130 is integrated into the system 100. In one or more embodiments, the microwave sub-arrays of the omnidirectional antenna array 104 are configured to operate at high GHz frequencies (e.g., 10 GHz, 24 GHz or higher). The processor 130 configures the operation of the microwave antenna array by turning on a single microwave sub-array or multiple microwave sub-arrays to operate in an omnidirectional mode or a directional mode. In one or more embodiments, the processor 130 can configure the amplitude and phase distribution within the antenna array to provide desired radiation characteristics.

[0040] Figure 2 depicts a dual - antenna system 200 with a common input 202 for a monopole 204 and an omnidirectional antenna array 206. The dual - omnidirectional antenna system 200 includes components similar to the Figure 1 components shown. For example, the multi - arm folded monopole 204 and the omnidirectional antenna array 206 have multiple microwave sub - arrays 216.

[0041] The microwave sub - arrays 216 can be operated using separate transmit and receive antennas. Alternatively, the microwave sub - arrays 216 can be operated using a common transmit and receive antenna. Figure 2 depicts the common input 202 of the antenna system 200.

[0042] In some embodiments, a processor 230 is integrated into the system 200. In one or more embodiments, a low - pass filter (LPF) 210 allows ultra - high - frequency (UHF) signals to pass through and blocks the flow of microwave current into the monopole while minimizing losses.

[0043] In a non - limiting example, the LPF 210 may be required in one of the antenna arrays and is connected, as shown, to the last patch of the microwave sub - array 216. One of the arms of the monopole 204 is connected to the LFP 210 at interface 212, while the other arms are connected to the ground plane of the microwave sub - array at interface 214. In a non - limiting example, a single microwave sub - array 216 is operable while the other sub - arrays 216 are used to connect the arms of the multi - arm folded monopole.

[0044] Figure 3 depicts a flowchart of a method 300 for operating a dual - antenna system according to one or more embodiments. The method 300 can be implemented using the antenna systems 100, 200 or other similar types of antenna systems. The method 300 begins at block 302 and proceeds to block 304, which specifies operating a first antenna. In one or more embodiments, the first antenna is an omnidirectional antenna array.

[0045] Block 306 operates a second antenna, where the second antenna is coupled to the first antenna. The second antenna is a multi - arm folded monopole having multiple arms. The multi - arm folded monopole is configured for communication and can be configured with an independent input. In other embodiments, the multi - arm folded monopole can be configured with a common input with the omnidirectional antenna array. In the case of sharing an input between the multi - arm folded monopole and the omnidirectional antenna array, an LPF filter can be used to separate the received signals.

[0046] The frame 308 couples the ground plane of the first antenna to the ground plane of the second antenna. The ground plane is shared between the first and second antennas. This can reduce the size of the antenna system. Method 300 ends at block 310, but it should be understood that additional steps or different sequences of steps can be performed and are not limited by Figure 3 the steps shown.

[0047] Figure 4A and Figure 4B depict the antenna characteristics of a dual-omni system. Figure 4A shows the azimuth plane = 90° of the far-field pattern when the omnidirectional antenna array is operating in the omnidirectional radiation mode. As shown, there are no nulls or gaps in the radiation of the signal, and the pattern shows the energy effectively transmitted in each direction.

[0048] Figure 4B shows the far-field pattern of the antenna system while it is operating in the directional mode or the sector scan radiation mode, where a single sub-array of the omnidirectional antenna array is used. Figure 4A and Figure 4B indicate that the omnidirectional antenna array remains viable during the operation of the multi-arm folded monopole (the multi-arm folded monopole is integrated into the antenna system) and significantly reduces interference while operating in both the omnidirectional mode and the directional mode.

[0049] Figure 5A , Figure 5B and Figure 5C depict the antenna characteristics of the multi-arm folded monopole according to one or more embodiments. The folded monopole can be the folded monopole implemented in the antenna systems 100, 200. The gain G ( , ) of the folded monopole antenna is shown at different frequencies. Figure 5A shows a graph representing the frequency of 433 MHz. As shown at = 0°, 45° and 90°, favorable gain characteristics are provided.

[0050] Figure 5B and Figure 5C show graphs representing the frequencies of 868 MHz and 2.4 GHz respectively and also provide favorable gain characteristics. Figures 5A - 5C shows that the operating performance of the monopole remains viable during the operation of the omnidirectional antenna array and communication is achieved simultaneously using different technologies (LoRa, ZigBee, WiFi).

[0051] Figure 6 depicts representing, for example, Figure 1Graph 600 of the input impedance of the multi-arm folded monopole of the integrated antenna system shown. Graph 600 shows a 5-arm monopole normalized to 50 ohms. The input impedance (Zin) can be expressed by the following Equation 1:

[0052] (Equation 1)

[0053] Where R represents the active part, and X represents the reactive part. This case includes a multi-arm folded monopole with a ground plane higher than λ / 4. The active part (R) of the input impedance can be calculated according to the following Equation 2:

[0054] (Equation 2)

[0055] Where R 0 is the radiation resistance of the single-wire monopole; n is the number of wires of the multi-arm folded monopole.

[0056] Therefore, an electrically small multi-arm folded monopole with a large ground plane can provide high efficiency. However, the resistance of a monopole with a small ground plane drops sharply. The technology of the embodiments described herein provides that a 5-arm monopole with a short ground plane can provide a high resistance (50 ohms) over a wide range. The reactive part of the input impedance (Zin) can be reduced by implementing a matching circuit to achieve simultaneous operation at different frequencies.

[0057] The frequencies 433 MHz, 868 MHz, and 2.4 GHz are provided by the corresponding curves m1, m2, m3 on Graph 600. As shown, the active parts (R) are 0.93, 1.12, and 1.14, with quality factors (Q) of 23.03, 4.96, and 1.23 respectively. The increase in system efficiency and the improved input impedance of the communication antenna (especially if it is electrically small) can relax the requirements of the transmitting and receiving parts.

[0058] The technical effects and benefits include combining a folded monopole and a microwave sub-array into a single omnidirectional antenna system. The occupied space of a communication system integrating a multi-arm folded monopole and an omnidirectional antenna array is reduced, and reduced mutual distortion is also provided. Due to the reduced size of the communication system, the cost of manufacturing the housing of the antenna system can be reduced.

[0059] The dual architecture prevents one antenna from obstructing the other, thus improving the combined performance of the antennas. A simplified dual architecture is provided, the installation time is reduced, and there is no need to focus on positioning the communication antenna during installation. The dual architecture improves the omnidirectional pattern of the communication antenna in each direction, such that there are no null values in the communication links.

[0060] As described above, embodiments can take the form of processes implemented by a processor and apparatus for implementing those processes (e.g., a processor). Embodiments can also take the form of computer program code embodied in a tangible medium such as a network cloud storage, SD card, flash drive, floppy disk, CD ROM, hard disk drive, or any other computer-readable storage medium, wherein when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for implementing the embodiments. Embodiments can also take the form of computer program code, for example, whether stored in a storage medium, loaded into and / or executed by a computer, or transmitted via some transmission medium, loaded into and / or executed by a computer, or transmitted via some transmission medium (e.g., via electrical wiring or cable, through fiber optics, or via electromagnetic radiation), wherein when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for implementing the embodiments. When implemented on a general microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.

[0061] This detailed description presents one or more embodiments of the disclosed devices and methods by way of illustration and not limitation with reference to the accompanying drawings.

[0062] The term “about” is intended to include the degree of error associated with a particular quantity of measurement based on the equipment available at the time of filing the present application.

[0063] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the disclosure. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when used in this specification, the terms “comprises” and / or “comprising” specify the presence of the 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.

[0064] Although the disclosure has been described with reference to one or more exemplary embodiments, those skilled in the art will understand that various changes can be made and equivalents can be substituted for its elements without departing from the scope of the disclosure. In addition, various modifications can be made to adapt a particular situation or material to the teachings of the disclosure without departing from its essential scope. Therefore, it is intended that the disclosure not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out the disclosure, but that the disclosure will include all embodiments falling within the scope of the claims.

Claims

1. A bi - directional antenna system, comprising: an antenna of a first type, and a second - type antenna integrated with the first - type antenna; wherein the first - type antenna comprises: a first input configured to receive a first input signal; a plurality of sub - arrays configured for transmitting and receiving a first set of signals; a first ground plane; wherein the second - type antenna comprises: a second input configured to receive a second input signal; a plurality of arms configured for transmitting and receiving a second set of signals, wherein a part of each of the plurality of arms comprises one of the plurality of sub - arrays; a second ground plane coupled to the first ground plane; wherein the second - type antenna integrated with the first - type antenna keeps the mutual interference between the first - type antenna and the second - type antenna below a level that would distort the operation of the first - type antenna and the second - type antenna.

2. The system according to claim 1, wherein the first - type antenna is an omnidirectional antenna array, and wherein the second - type antenna is a multi - arm folded monopole antenna, and wherein at least one of the plurality of arms is connected to the first ground plane of at least one of the sub - arrays.

3. The system according to claim 1, wherein each of the plurality of sub - arrays comprises a top layer and a bottom layer, wherein the bottom layer comprises the first ground plane, and wherein the top layer comprises a plurality of radiation patches.

4. The system according to claim 1, wherein the first input and the second input comprise a common input.

5. The system according to claim 3, wherein at least one of the plurality of sub - arrays comprises a low - pass filter, and wherein the low - pass filter is connected to one of the plurality of radiation patches.

6. The system according to claim 5, wherein the low - pass filter is arranged between one of the plurality of arms of the second - type antenna and one of the plurality of radiation patches.

7. The system according to claim 6, wherein the radiation patch connected to one of the plurality of arms is located at the top of the sub - array.

8. The system according to claim 1, wherein the first - type antenna and the second - type antenna operate in different frequency bands.

9. The system according to claim 8, wherein the first - type antenna operates in the microwave band, and the second - type antenna operates in the ultra - high - frequency band.

10. The system according to claim 1, wherein the plurality of sub - arrays of the first - type antenna are arranged in a circular layout.

11. A computer - implemented method for operating an omnidirectional antenna system, the computer - implemented method comprising: operating a first - type antenna, and operating a second - type antenna integrated with the first - type antenna; wherein the first - type antenna comprises: a first input configured to receive a first input signal; a plurality of sub - arrays configured for transmitting and receiving a first set of signals; a first ground plane; wherein the second - type antenna comprises: a second input configured to receive a second input signal; a plurality of arms configured for transmitting and receiving a second set of signals, wherein a part of each of the plurality of arms comprises one of the plurality of sub - arrays; A second ground plane coupled to the first ground plane; wherein, the second type of antenna integrated with the first type of antenna keeps the mutual interference between the first type of antenna and the second type of antenna below a level that would distort the operation of the first type of antenna and the second type of antenna.

12. The computer-implemented method according to claim 11, wherein the first type of antenna is an omnidirectional antenna array, and wherein the second type of antenna is a multi-arm folded monopole antenna.

13. The computer-implemented method according to claim 11, further comprising connecting at least one of the plurality of arms to the first ground plane of at least one sub-array in the sub-arrays.

14. The computer-implemented method according to claim 11, wherein each of the plurality of sub-arrays includes a top layer and a bottom layer, wherein the bottom layer includes the first ground plane, and wherein the top layer includes a plurality of radiating patches.

15. The computer-implemented method according to claim 14, further comprising receiving an input, wherein the first input and the second input include a common input; and filtering the received input, wherein the input is filtered using a low-pass filter, wherein the low-pass filter is positioned in at least one of the plurality of sub-arrays, and wherein the low-pass filter is connected to one of the plurality of radiating patches.

16. The computer-implemented method according to claim 15, wherein the low-pass filter is arranged between one of the plurality of arms of the second type of antenna and one of the plurality of radiating patches.

17. The computer-implemented method according to claim 16, wherein the radiating patch connected to one of the plurality of arms is located at the top of the sub-array.

18. The computer-implemented method according to claim 11, wherein the first type of antenna and the second type of antenna operate in different frequency bands.

19. The computer-implemented method according to claim 11, wherein operating the first type of antenna includes operating in the microwave and millimeter (mm) wave bands, and operating the second type of antenna includes operating in the ultra-high frequency band or the microwave band.

20. The computer-implemented method according to claim 11, further comprising arranging the plurality of sub-arrays of the first type of antenna in a circular arrangement.

21. A dual-omnidirectional antenna system, comprising: a first antenna, wherein the first antenna includes: a first input configured to receive an input signal; a plurality of sub-arrays configured for transmitting and receiving signals; the ground plane of the first antenna; and a second antenna coupled to the first antenna, wherein the second antenna includes: a second input configured to receive an input signal; a plurality of arms configured for transmitting and receiving signals; the ground plane of the second antenna, wherein the ground plane of the first antenna is coupled to the ground plane of the second antenna; wherein the first antenna is an omnidirectional antenna array, and wherein the second antenna is a multi-arm folded monopole antenna, and at least one of the plurality of arms is connected to the ground plane of the first antenna of at least one sub-array in the sub-arrays.

22. A computer-implemented method for operating an omnidirectional antenna system, the computer-implemented method comprises: operating a first antenna, wherein the first antenna comprises: a first input configured to receive an input signal; a plurality of sub-arrays configured for transmitting and receiving signals; a ground plane of the first antenna; operating a second antenna coupled to the first antenna, wherein the second antenna comprises: a second input configured to receive an input signal; a plurality of arms configured for transmitting and receiving signals; a ground plane of the second antenna; and coupling the ground plane of the first antenna and the ground plane of the second antenna; wherein the first antenna is an omnidirectional antenna array, and wherein the second antenna is a multi-arm folded monopole antenna, and wherein at least one of the plurality of arms is connected to the ground plane of at least one of the sub-arrays of the first antenna.

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