The subject disclosure generally relates to an antenna device in the field of communications, and in particular to a waveguide fed open slot antenna.
In wireless communication and radar systems, transmission and reception of signals rely on antennas. In recent years, various applications based on wireless technology have proliferated, both in microwave frequency bands and millimeter-wave frequency bands. However, the growing amount of wireless sub-systems on the same platform requires more antennas, which increases complexity and cost of the whole system. To solve this problem, many technologies have been proposed to develop wideband antennas with simple structure and low cost. However, such technologies have had some drawbacks, some of which may be noted with reference to the various embodiments described herein below.
Non-limiting embodiments of the subject disclosure are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.
Aspects of the subject disclosure will now be described more fully hereinafter with reference to the accompanying drawings in which example embodiments are shown. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the various embodiments. However, the subject disclosure may be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein.
Compared with a narrowband antenna, a wideband antenna can serve multiple applications at different frequency bands simultaneously, and can support broadband systems with high data transmission rates. In addition, antennas with a simple structure can reduce the difficulty and cost of processing, which can be especially attractive for millimeter-wave applications.
In the prior art, a slot antenna is a kind of antenna with simple structure. It can be used for millimeter-wave applications because such an antenna can be conveniently processed using a low-cost printed circuit board (PCB) technology. However, the main drawback of the slot antenna is that its bandwidth is narrow.
To these and/or related ends, various embodiments disclosed herein provide for an improved waveguide fed open slot antenna that achieves a wide bandwidth based on the simple structure of the slot antenna. In embodiments, and in contrast to the traditional slot antenna, only two sides of the slot (sometimes referred to as an “open slot”) are connected to metal, whereas the other two sides are open (i.e., not connected to metal), and the waveguide is used to feed the slot. These approaches can be applied to both the traditional microwave frequency band and the millimeter wave frequency band, and can be utilized as an element of an antenna array.
Compared with a conventional waveguide slot antenna, in embodiments, two long sides of a slot of a waveguide fed open slot antenna have metal boundaries, while two short sides do not have metal boundaries—i.e., it is an open structure. In order to excite the slot, one long side of the slot can be connected to, the top surface of the waveguide section, and the other long side can be connected to, the waveguide bottom extension (sometimes referred to as a “waveguide extension”) by the vertical metal wall (sometimes referred to as a “metal wall”). A wide bandwidth and a stable gain can be achieved by selecting an appropriate waveguide height, H, and adjusting the length of the short side of the slot, S. A matching load with appropriate length can help to further expand the bandwidth and make the patterns more symmetrical. The antenna can be used as an element in antenna arrays.
To the extent that the terms “includes,” “has,” “contains,” and other similar words are used in either the detailed description or the appended claims, such terms are intended to be inclusive—in a manner similar to the term “comprising” as an open transition word—without precluding any additional or other elements. Moreover, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is, unless specified otherwise, or clear from context, “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then “X employs A or B” is satisfied under any of the foregoing instances. In addition, the articles “a” and “an” as used in this application and the appended claims should generally be construed to mean “one or more” unless specified otherwise or clear from context to be directed to a singular form.
It is to be appreciated that the term “substantially” in conjunction with another term as used herein is intended to refer an attempt to achieve a desired outcome associated with the other term while being within an acceptable tolerance of the desired outcome. For example, “substantially equal” can equate to “equal” with an acceptable tolerance, such as manufacturing variances when attempting to achieve “equal” may be within acceptable tolerances while not being exactly “equal.”
Further, the word “exemplary” and/or “demonstrative” is used herein to mean serving as an example, instance, or illustration. For the avoidance of doubt, the subject matter disclosed herein is not limited by such examples. In addition, any aspect or design described herein as “exemplary” and/or “demonstrative” is not necessarily to be construed as preferred or advantageous over other aspects or designs, nor is it meant to preclude equivalent exemplary structures and techniques known to those of ordinary skill in the art having the benefit of the instant disclosure.
It can be understood that, herein, the terms “longitudinal,” “lateral,” and “vertical” are used for convenience and clarity of description and are based on the ground plane occupying a horizontal plane. The use of these and similar terms, such as “top,” “bottom,” and “upper” should not be taken as implying any limitation on the orientation of the antenna. Furthermore, it can be appreciated that terms such as a first side of an object and a second side of the object can be used to refer to a top and bottom of the object, respectively, and that a similar approach can be used to describe other portions of various objects.
Referring now to
In the example of
In one or more embodiments, a waveguide fed open slot antenna comprises the waveguide section 101, the slot 102, the matching load 103, the waveguide bottom extension 104, and the vertical metal wall 105.
The antenna excitation port 106 can be the port of the waveguide section 101 that is positioned away from the slot 102. The vertical metal wall 105 can be constructed by a row of metalized vias. The width of the vertical metal wall 105 (in the lateral direction) and the width (in the lateral direction) of the slot 102 can be equal in the lateral direction. The top end of the vertical metal wall 105 can be connected to the edge of the matching load 103, which is close to the slot 102.
The waveguide bottom extension 104 can be rectangular, and can be formed by extending the bottom metal wall of the waveguide section 112 along the longitudinal direction. An end of the waveguide bottom extension 104 can connect to the bottom end of the vertical metal wall 105. The height (in the vertical direction) of the vertical metal wall 105 can be equal to the height (in the vertical direction) of the waveguide section 101. The antenna can be processed by PCB technology.
The width a 115 of the waveguide section can ensure that the waveguide operates in a transverse electric 10 (TE10) mode. In order to achieve impedance matching in a wide frequency band, the height H 118 of the waveguide section can be utilized as a parameter. For example, a Rogers Duroid 5880 high frequency laminate with a thickness of 0.508 millimeters (mm), and a dielectric constant of 2.2 can be selected as the dielectric substrate, with a thickness of about 0.19λ (where λ represents the dielectric wavelength at the operating center frequency). The width S 116 of the slot is another parameter that can affect the impedance matching, which is about 0.26λ in this example. The matching load can further expand the bandwidth, and the matching load can take the form of a rectangular patch with a width L 117 of about 0.37λ.
Example dimensions (in mm) for the antenna structure in
The width (in the lateral direction) of the vertical metal wall 105 can be equal to that of the slot 102, and the height (in the vertical direction) of the vertical metal wall 105 can be equal to that of the waveguide section 101. The top of the vertical metal wall 105 can be connected to an edge of the matching load 103 on the side close to the slot 102. The bottom of the metal wall 105 can be connected to an edge of the waveguide bottom extension 104.
In one or more alternative embodiments, the waveguide section 101 can be a SIW, and the entire antenna can be built on a dielectric substrate 107, where the vertical metal wall 105 can be constructed with a row of metalized vias 114. A metalized via is generally a metal structure that connects two metal layers in an electrical circuit. The matching load 103 can take many possible forms. For example, in an alternative embodiment, the matching load 103 can comprise a piece of metal patch and can be located in the same plane as the slot 102. In this embodiment, the metal patch can be rectangular, triangular, semi-circular, or polygonal.
In one or more additional alternative embodiments, the matching load 103 can include an upper metal patch, a lower metal patch, and metalized vias. The upper metal patch and the lower metal patch can have the same shape and they can overlap each other after shifted along the vertical direction. The upper metal patch and the slot 102 can be in the same plane, and the lower metal patch and the waveguide bottom extension 104 can be in the same plane. An edge of the upper metal patch can be connected with an edge of the lower metal patch by the metalized vias. In this embodiment, the metal patches can be rectangular, triangular, semi-circular, or polygonal.
In one or more additional alternative embodiments, the waveguide section can be a rectangular waveguide, where the matching load 103 can take many possible forms. For example, in an alternative embodiment, the matching load 103 can be a piece of metal patch and can be in the same plane as the slot 102. In this embodiment, the metal patch can be rectangular, triangular, semi-circular, or polygonal. In another alternative embodiment, the matching load 103 can be a metal block. The top and bottom surfaces of the metal block can have the same shape and they can overlap each other after shifted along the vertical direction. The top surface of the metal block and the slot 102 can be in the same plane, and the bottom surface of the metal block and the waveguide bottom extension 104 can be in the same plane. One side of the metal block that is near the slot 102 can be coincident with the vertical metal wall 105. In this embodiment, the top surface of the metal block can be rectangular, triangular, semi-circular, or polygonal. In order to reduce the size of the antenna, the interior of the rectangular waveguide, and the space between the slot and the waveguide bottom extension can be filled with dielectric material.
The embodiment of
The matching load for the antenna can take many different forms other than the rectangular metal patch shown in
The waveguide section of the antenna can also adopt a rectangular waveguide, while the antenna has a metal structure as a whole, as shown in
In order to reduce antenna size, in
An antenna such as described herein can be used as a basic element to construct an antenna array.
An antenna in accordance with embodiments of the present disclosure can provide for excellent performance (such as wide bandwidth), a simple structure, and a low fabrication cost. The wide bandwidth provided by such an antenna can make it highly attractive for the development of various kinds of indoor and outdoor base station antennas for modern cellular communication systems, since this wide bandwidth can cover multiple frequency bands of different applications. In addition, the antenna can have a simple structure, and can be fabricated with a low-cost PCB technology for millimeter-wave applications. Additionally, the antenna can also be used as a basic element in the design of a low-cost and high-performance antenna array with different gain and beam widths.
The above description of illustrated embodiments of the subject disclosure, including what is described in the Abstract, is not intended to be exhaustive or to limit the disclosed embodiments to the precise forms disclosed. While specific embodiments and examples are described herein for illustrative purposes, various modifications are possible that are considered within the scope of such embodiments and examples, as those skilled in the relevant art can recognize.
In this regard, while the disclosed subject matter has been described in connection with various embodiments and corresponding Figures, where applicable, it is to be understood that other similar embodiments can be used or modifications and additions can be made to the described embodiments for performing the same, similar, alternative, or substitute function of the disclosed subject matter without deviating therefrom. Therefore, the disclosed subject matter should not be limited to any single embodiment described herein, but rather should be construed in breadth and scope in accordance with the appended claims below.
Number | Name | Date | Kind |
---|---|---|---|
4704589 | Moeller | Nov 1987 | A |
5541612 | Josefsson | Jul 1996 | A |
5638079 | Kastner et al. | Jun 1997 | A |
5831583 | Lagerstedt et al. | Nov 1998 | A |
9368878 | Chen et al. | Jun 2016 | B2 |
9620841 | Tong | Apr 2017 | B2 |
10020591 | Uemichi | Jul 2018 | B2 |
10050336 | Wang | Aug 2018 | B2 |
10199743 | Cheng | Feb 2019 | B2 |
10299368 | Huang | May 2019 | B2 |
10522919 | Pucci | Dec 2019 | B2 |
20090066597 | Yang et al. | Mar 2009 | A1 |
Number | Date | Country |
---|---|---|
104092028 | Oct 2014 | CN |
205004441 | Jan 2016 | CN |
0440126 | Aug 1991 | EP |
Entry |
---|
Zhang et al., “Wideband Millimeter-Wave Substrate Integrated Waveguide Slotted Narrow-Wall Fed Cavity Antennas,” IEEE Transactions on Antennas and Propagation, vol. 59, No. 5, pp. 1488-1496, May 2011, 9 pages. |
Gong et al., “Substrate Integrated Waveguide Cavity-Backed Wide Slot Antenna for 60-GHz Bands,” Transactions on Antennas and Propagation, vol. 60, No. 12, pp. 6023-6026, Dec. 2012, 4 pages. |
Guan et al., “An SIW Based Large-Scale Corporate-Feed Array Antenna,” IEEE Transactions on Antennas and Propagation, vol. 63, No. 7, pp. 2969-2976, Jul. 2015, 8 pages. |
Yang et al., “Wideband Millimeter-Wave Substrate Integrated Waveguide Cavity-Backed Rectangular Patch Antenna,” IEEE Antennas and Wireless Propagation Letters, vol. 13, 2014, pp. 205-208, 4 pages. |
Yan et al., “Simulation and Experiment on SIW Slot Array Antennas,” IEEE Microwave and Wireless Components Letters, vol. 14, No. 9, Sep. 2004, pp. 446-448, 3 pages. |
Ding et al., “A 4×4 Ridge Substrate Integrated Waveguide (RSIW) Slot Array Antenna,” IEEE Antennas and Wireless Propagation Letters, vol. 8, 2009, pp. 561-564, 4 pages. |
Chen et al., “Low-Cost High Gain Planar Antenna Array for 60-GHz Band Applications,” IEEE Transactions on Antennas and Propagation, vol. 58, No. 6, Jun. 2010, pp. 2126-2129, 4 pages. |
Mbaye et al., “Bandwidth Broadening of Dual-Slot Antenna Using Substrate Integrated Waveguide (SIW)” IEEE Antennas and Wireless Propagation Letters, vol. 12, 2013, pp. 1169-1171, 3 pages. |
Miura et al., “Double-Layer Full-Corporate-Feed Hollow-Waveguide Slot Array Antenna in the 60-GHz Band,” IEEE Transactions on Antennas and Propagation, vol. 59, No. 8, Aug. 2011, pp. 2844-2851, 8 pages. |
Li et al., “Low-Cost High-Gain and Broadband Substrate- Integrated-Waveguide-Fed Patch Antenna Array for 60-GHz Band,” IEEE Transactions on Antennas and Propagation, vol. 62, No. 11, Nov. 2014, pp. 5531-5538, 9 pages. |
Zhu et al., “Substrate-Integrated-Waveguide-Fed Array Antenna Covering 57-71 GHz Band for 5G Applications,” IEEE Transactions on Antennas and Propagation, vol. 65, No. 12, Dec. 2017, pp. 6298-6306, 9 pages. |
Xu et al., “Bandwidth Enhancement for a 60 GHz Substrate Integrated Waveguide Fed Cavity Array Antenna on LTCC,” IEEE Transactions on Antennas and Propagation, vol. 59, No. 3, Mar. 2011, pp. 826-832, 7 pages. |
Li et al., “60-GHz Substrate Integrated Waveguide Fed Cavity-Backed Aperture-Coupled Microstrip Patch Antenna Arrays,” IEEE Transactions on Antennas and Propagation, vol. 63, No. 3, Mar. 2015, pp. 1075-1085, 11 pages. |
Number | Date | Country | |
---|---|---|---|
20200014118 A1 | Jan 2020 | US |