Patent Grant
9385416
Embodiments of the disclosure relate to the field of communications, and in particular, to a wireless network device adapted with an antenna configuration for improved spatial/pattern diversity and/or spatial polarization.
Over the last decade or so, electronic devices responsible for establishing and maintaining wireless connectivity within a wireless network have increased in complexity. For instance, wireless electronic devices now support greater processing speeds and greater data rates. As a by-product of this increase in complexity, radio communications techniques have evolved with the emergence of multiple-input and multiple-output (MIMO) antenna architectures.
In general, MIMO involves the use of multiple antennas operating as transmitters and/or receivers to improve communication performance. Herein, multiple radio channels are used to carry data within radio signals transmitted and/or received via multiple antennas. As a result, in comparison with other conventional antenna architectures, MIMO antenna architectures offer significant increases in data throughput and link reliability (reducing fading) without increased transmit power.
Currently, in wireless access points for example, MIMO antennas are deployed on a flat surface commonly used as a heat sink. This deployment fails to optimize spatial diversity, polarization diversity or pattern diversity in order to optimize antenna performance.
The disclosure may best be understood by referring to the following description and accompanying drawings that are used to illustrate embodiments of the disclosure.
Embodiments of the disclosure relate to a wireless network device adapted with an antenna dome array. Besides operating as a cover for a heat dissipation unit that protects wireless logic from environmental effects and dissipates heat generated by the wireless logic by convection, the antenna dome array also provides a surface for multiple antenna elements. These antenna elements are positioned to provide a greater angular diversity for the antenna patterns radiating from these antenna elements.
According to one embodiment of the disclosure, the antenna dome array comprises a downward curved, outer periphery (having a general convex shape) onto which multiple antenna elements are placed. In communication with wireless logic, these antenna elements are positioned to achieve improved spatial diversity, polarization and pattern diversity. The antenna dome array may be shaped to feature a convex-shaped top surface with different radius of curvature through different segments of the antenna dome array (e.g. a higher radius of curvature toward a center area with convex-shaped top surface with a lesser radius of curvature at the outer periphery).
In particular, improved spatial diversity may be achieved in providing more spacing among antenna elements transmitting and/or receiving wireless signals in the same radio frequency (RF) band. Furthermore, improved polarization and pattern diversity may be achieved by minimizing correlation among antenna elements through an arrangement of antenna elements in different orientations and reducing Envelope Correlation Coefficient (ECC) by varying directional patterns.
Herein, certain terminology is used to describe features of the disclosure. For example, the term “logic” is generally defined as hardware and/or software. As hardware, logic may include circuitry such as processing circuitry (e.g., a microprocessor, a programmable gate array, a controller, an application specific integrated circuit, etc.), wireless receiver, transmitter and/or transceiver circuitry, semiconductor memory, combinatorial logic, or the like. As software, the logic may be one or more software modules, which are executable code such as an application, an applet, a routine, or one or more instructions. Software modules may be stored in any type of memory, namely suitable storage medium such as a programmable electronic circuit, a semiconductor memory device including a volatile memory (e.g., random access memory, etc.), any type of non-volatile memory (e.g., read-only memory, flash memory, a hard drive, etc.), a portable memory device (e.g., an optical disk, a Universal Serial Bus “USB” flash drive), or the like.
A “wireless network device” generally represents an electronic unit that supports wireless communications such as an Access Point (AP), a station (e.g., any data processing equipment that is operable by a user such as a computer, cellular phone, personal digital assistant, tablet computer, etc.), a data transfer device (e.g., wireless network switch, wireless router, brouter, etc.), or the like.
An “interconnect” is generally defined as a communication pathway established over an information-carrying medium. This information-carrying medium may be a physical medium (e.g., electrical wire, optical fiber, cable, bus traces, etc.), a wireless medium (e.g., air in combination with wireless signaling technology), or a combination thereof.
Lastly, the terms “or” and “and/or” as used herein are to be interpreted as inclusive or meaning any one or any combination. Therefore, “X, Y or Z” or “X, Y and/or Z” mean “any of the following: X; Y; Z; X and Y; X and Z; Y and Z; X, Y and Z.” An exception to this definition will occur only when a combination of elements, functions, steps or acts are in some way inherently mutually exclusive.
Certain details are set forth below in order to provide a thorough understanding of various embodiments of the disclosure, albeit the invention may be practiced through many embodiments other that those illustrated. Well-known logic and operations are not set forth in detail in order to avoid unnecessarily obscuring this description.
Referring to
As shown in this embodiment, AP 110 comprises logic, implemented within a casing 120, that controls wireless communications with other wireless network devices (STAs) 1301-130r (where r≧1, r=3 for this embodiment) and/or wired communications over interconnect 140. Although not shown, interconnect 140 further provides connectivity for network resources such as servers for data storage, web servers, or the like. These network resources are available to network users via STAs 1301-130r of
More specifically, for this embodiment of the disclosure, each AP 110-112 supports bi-directional communications by receiving wireless messages from any STAs 1301-130r within its coverage area. For instance, as shown as an illustrative embodiment of a network configuration, STA 1301 may be associated with AP 110 and communicates over the air in accordance with a selected wireless communications protocol. Hence, AP 110 may be adapted to operate as a transparent bridge connecting together a wireless and wired network.
Of course, in lieu of providing wireless transceiver functionality, it is contemplated that AP 110 may only support unidirectional transmissions thereby featuring only receive (RX) or transmit (TX) functionality.
Referring now to
More specifically, wireless logic 200 is contained within a cavity 220 formed by base section 230 of heat dissipation unit 210. A cover section 240, forming part of an antenna dome array (described below), is placed over and rests upon an opening edge 232 of base section 230. Both base section 230 and cover section 240 of heat dissipation unit 210 are made of a heat-radiating material in order to dissipate heat by convection. For example, this heat-radiating material may include aluminum or any other metal, combination of metals or a composite that conducts heat.
As further shown in
Additionally, according to one embodiment of the disclosure, cover section 240 of heat dissipation unit 210 is configured with a convex shape that is sized for mating with base section 230. For instance, a second flange 242 extends around an inner periphery of cover section 240 so that second flange 242 rests in recessed groove 236 formed between first flange 234 and edge 238 of base section 230.
A heat transfer path from wireless logic 200 to base section 230 and/or cover section 240 is provided by thermal elements 280-282. These elements 280-282 are positioned so that wireless logic 200 establishes thermal contact with cover section 240 and/or base section 230 when circuit board 260 is situated in base section 230 and cover section 240 is placed over base section 230.
Herein, a plurality of light emitting diodes (LEDs) 290 are positioned on or proximate to circuit board 260 and aligned with apertures 244 placed within cover section 240. This enables emission of light to represent status information concerning wireless network device 110 (e.g., state of operation, level of work load, etc.).
Referring now to
Referring now to
Furthermore, according to one embodiment of the disclosure, each antenna element 4101, 4102 and 4103 may be separated from each other by a uniform degree of separation. In other words, using a center point 315 of cover section 240 as a reference point, each antenna element operating in the same frequency band is separate from its neighboring antenna element by approximately 360/n degrees (120° for n=3).
According to another embodiment of the disclosure, antenna element 4102 and 4103 may be separated from antenna element 4101 by a first angle of separation while antenna element 4102 and 4103 are separated from each other by a second angle of separation. The first angle of separation is greater than the second angle of separation. For instance, antenna element 4102 and 4103 may have a second angle of separation equal to approximately ninety degree) (90° while the first degree of separation between antenna elements 4101/4102 and/or 4101/4103 may be approximately one-hundred thirty-five (135°). Element 4201, 4202 and 4203 are positioned generally opposite from antenna elements 4101, 4102 and 4103, respectively.
Referring back to
Furthermore, in lieu of placing base members 4151-4153 on a substantially horizontal surface, base members 4151-4153 are placed on a convex-shaped outer periphery that tilts antenna elements 4101-4103 upward by a prescribed angle offset from horizontal. For instance, with respect to antenna element 4101, its base member 4151 is positioned on top surface 340 so that antenna element 4101 is angled at a first angle (A) 350 offset from horizontal 360. Likewise, base member 4251 of antenna element 4151 is positioned on top surface 340 so that antenna element 4151 is angled at a second angle (B) 370 offset from horizontal 360.
According to one embodiment of the disclosure, first angle A 350 may be equal to approximately 14° (e.g.) A≈14.5° with second angle B 370 being equivalent to first angle A 350 (e.g.) B≈14.5°. However, it is contemplated that first angle A 350 may have an angle ranging between 10°-20° and second angle B 370 may have an angle ranging between 10°-20°, where angles A and B may be equivalent to each other or different from one another.
Referring now to
According to one embodiment of the disclosure, a distance D1540 from a first edge 520 of cover section 240 to base member 4151 is approximately equal to 30-34 millimeters (mm) (e.g. 31.6 mm) and a distance D2550 from a second edge 525 of cover section 240 to base member 4251 is approximately equal to 30-34 mm (e.g., 33.2 mm). Diameter 510 is approximately 190 mm and the distance between base members 4151 and 4251 is approximately 125 mm.
Furthermore, as shown in
Hence, as shown in
According to one embodiment of the disclosure, first antenna element 4101 is positioned on a corner 600 of outer periphery 320 opposite from a corner 610 featuring second antenna element 4102. Similarly, antenna elements 4201 and 4202, which operate in the same frequency band, are positioned on different corners 620 and 630 of outer periphery 320. Hence, each antenna element operating in the same frequency band (e.g., antenna elements 4101-4102 and antenna elements 4201-4202) is separated from each other by a uniform degree of separation. In other words, using a center point 640 of cover section 240 as a reference point, each antenna element operating in the same frequency band is separated from its neighboring antenna element by approximately 180° degrees and placed within the corner for maximum spatial separation.
Referring to
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the disclosure in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as determined by the appended claims and their equivalents. The description is thus to be regarded as illustrative instead of limiting.
| Number | Name | Date | Kind |
|---|---|---|---|
| 20110102281 | Su | May 2011 | A1 |
| 20120155015 | Govindasamy et al. | Jun 2012 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20140197998 A1 | Jul 2014 | US |
