Patent Application
20120075162
1. Technical Field
Aspects of embodiments according to the present invention relate to antennas. More specifically, aspects of embodiments according to the present invention relate to antennas that plug into printed circuit boards (PCBs).
2. Brief Description of the Related Art
The prior art for the technology of low cost plug-in antennas, or antennas that connect to a chassis (e.g., a printed circuit board), either a discrete chassis or an array chassis, do not address all of the unique challenges. One problem is the high cost of fabricating and assembling antenna arrays using many of the prior art approaches, such as soldered connections, which do not lend themselves to low cost assembly using pick and place machines. For example, some designs need expensive connectors, which make them impractical for cost sensitive applications. Other designs do not offer wideband antenna efficiency, or sufficient bandwidth, or proper signal direction to provide the capability to be used in a phased array antenna.
Embodiments of the present invention address these problems by providing a low cost plug-in antenna for plugging directly into a printed circuit board (PCB). Embodiments of the present invention are directed to a low cost antenna that can be interfaced into a transceiver, either for discrete or array applications. Antennas that are easily assembled are less expensive to produce, thus allowing the costs to remain competitive. Embodiments of the present invention are further directed to a modularized antenna element that is designed to work efficiently over a broadband with simplified assembly requirements to be used in discrete or array applications.
According to an exemplary embodiment of the present invention, an antenna radiator is provided. The antenna radiator includes a radiator printed circuit board (PCB), a pair of opposing antenna elements, and a pair of tabs. The radiator PCB is for plugging into a backplane PCB via an edge card connector in a direction normal to the backplane PCB. The pair of antenna elements is on one side of the radiator PCB. The pair of tabs is electrically connected to corresponding ones of the pair of antenna elements. The tabs are connecting to the edge card connector when the radiator PCB is plugged into the backplane PCB.
The antenna radiator may further include a corresponding other pair of opposing antenna elements on another side of the radiator PCB.
The antenna radiator may further include a corresponding other pair of tabs electrically connected to corresponding ones of the other pair of antenna elements. The other tabs are for connecting to the edge card connector when the radiator PCB is plugged into the backplane PCB.
The pair of antenna elements may include a plurality of pairs of opposing antenna elements. The pair of tabs may include a plurality of pairs of tabs corresponding to the plurality of pairs of antenna elements.
The antenna radiator may further include a corresponding plurality of other pairs of opposing antenna elements on another side of the radiator PCB.
The antenna radiator may further include a corresponding plurality of other pairs of tabs. Each of the other pairs of tabs is electrically connected to corresponding ones of a respective pair of the other pairs of antenna elements.
The antenna elements may be arranged in a flared notch configuration.
A height of the antenna elements may be less than a half of a signal wavelength of the antenna radiator.
The pair of tabs may include a third tab.
According to another exemplary embodiment of the present invention, an antenna is provided. The antenna includes a radiator portion and a backplane portion. The radiator portion includes a radiator printed circuit board (PCB), a pair of opposing antenna elements, and a pair of tabs. The pair of opposing antenna elements is on one side of the radiator PCB. The pair of tabs is electrically connected to corresponding ones of the pair of antenna elements. The backplane portion includes a backplane PCB, wiring on the backplane PCB, and an edge card connector. The edge card connector is on the backplane PCB. The edge card connector is for allowing the radiator portion to plug into the backplane portion in a direction normal to the backplane PCB. The edge card connector is also for electrically connecting the wiring to the tabs.
The edge card connector may include connector pins. The connector pins are for securing the radiator portion when plugged into the backplane portion. The connector pins are also for electrically connecting the wiring to the tabs.
The wiring may include a balun.
The radiator portion may further include a corresponding other pair of opposing antenna elements on another side of the radiator PCB.
The radiator portion may further include a corresponding other pair of tabs. The other tabs are electrically connected to corresponding ones of the other pair of antenna elements and to the wiring.
The pair of antenna elements may include a plurality of pairs of opposing antenna elements. The pair of tabs may include a plurality of pairs of tabs corresponding to the plurality of pairs of antenna elements.
The edge card connector may include a plurality of edge card connectors corresponding to the plurality of pairs of antenna elements and the plurality of pairs of tabs.
The radiator portion may further include a corresponding plurality of other pairs of opposing antenna elements on another side of the radiator PCB.
The radiator portion may further include a corresponding plurality of other pairs of tabs.
Each of the other pairs of tabs is electrically connected to corresponding ones of a respective pair of the other pairs of antenna elements and to the wiring.
The antenna elements may be arranged in a flared notch configuration.
A height of the antenna elements may be less than a half of a signal wavelength of the antenna.
The pair of tabs may include a third tab.
According to yet another exemplary embodiment of the present invention, an antenna array is provided. The antenna array includes a plurality of radiator portions and a backplane portion. Each of the radiator portions includes a radiator printed circuit board (PCB), one or more pairs of opposing antenna elements, and one or more pairs of tabs. The one or more pairs of opposing antenna elements are on one side of the radiator PCB. The one or more pairs of tabs correspond to the one or more pairs of antenna elements. Each of the pairs of tabs is electrically connected to corresponding ones of a respective pair of the pairs of antenna elements. The backplane portion includes a backplane PCB, wiring on the backplane PCB, and one or more edge card connectors on the backplane PCB. The one or more edge card connectors are for allowing the radiator portions to plug into the backplane portion in a direction normal to the backplane PCB and parallel or coplanar with each other. Each of the edge card connectors is for connecting to one or more pairs of antenna elements and their corresponding one or more pairs of tabs. Each of the edge card connectors is also for electrically connecting the wiring to the corresponding one or more pairs of tabs.
Each of the radiator portions may further include a corresponding one or more other pairs of opposing antenna elements on another side of the radiator PCB.
Each of the radiator portions may further include a corresponding one or more other pairs of tabs. Each of the other pairs of tabs is electrically connected to corresponding ones of a respective pair of the other pairs of antenna elements and to the wiring.
In still yet another embodiment according to the present invention, a modular antenna array is provided. The modular antenna array includes an array of antenna arrays.
The accompanying drawings illustrate exemplary embodiments of the present invention, and together with the description, serve to explain aspects of the embodiments.
Exemplary embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. Like reference numerals refer to like elements throughout.
There are a variety of integration mechanisms for an antenna into an electronic system. Antennas that screw into the transceiver chassis often require manual tools, to insure correct installation. Antenna elements that solder in place can pose difficulties due to the 3-dimensional nature of antennas and processes that are geared to PCB planar soldering. For transceivers, such as wireless handsets, or radars that are capable of being serviced, simple disassembly is required to keep the service costs low and to minimize damage to the device. Other approaches include utilizing pins either soldered to the antenna boards or routed into the boards. However, these are not low cost solutions for assembly of parts onto a standard circuit board because the antenna element cannot be installed by a pick and place machine. In addition, maintenance becomes more expensive because soldering of the elements into the backplane board prevents removal of the elements for servicing.
Plug-in antennas provide the convenience of eliminating the need for external tools, and allow the antenna to be removed for service, test, and ease of assembly. Many transceivers are assembled using printed circuit board (PCB) techniques whereon electronic components are mounted using a pick and place process. It would be desirable to place antenna connectors directly onto the circuit board; connectors that are compatible with a pick and place process and which are produced in mass quantities for the computer and telecommunications industry. This, in turn, leads to lower costs than with traditional high performance radio frequency (RF) coaxial connectors. In addition, demands for multifunction and higher performance transceivers require increasing amounts of antenna bandwidth, thus creating new design challenges that require high performance antenna connections.
Embodiments of the plug-in antenna according to the present invention offer a low cost antenna assembly solution, using PCBs and edge card connectors compatible with a pick and place process and that can be produced in mass quantities. Such antennas are compatible with a wide variety of commercially available edge card connectors. The antenna elements can be impedance matched to edge card connectors over a broad band of frequency range. Further, the antenna elements can be arrayed and plug into a backplane for high gain or for electronically steered array applications.
The backplane portion 60 includes a backplane PCB 70 onto which is mounted an edge card connector 90 for connecting with the radiator portion 20. The backplane PCB 70 also has wiring 80 to transfer signals from the backplane PCB 70 to the edge card connector 90. The wiring 80 may also include a balun when conversion between unbalanced and balanced signals is warranted. The edge card connector 90 secures the radiator PCB 30 in a direction normal to the backplane PCB 70, and connects the backplane portion 60 to the antenna elements 40 via the tabs 50 using connector pins 55, which electrically connect the wiring 80 to the tabs 50.
The edge card connectors 190 of the backplane portion 160 are arranged in rows. Each row of edge card connectors 190 is configured to receive one or more radiator portions 120. As can be seen in the embodiment depicted in
Referring further to
Referring back to
The two antenna elements 40 have a feed gap of width G that is adjusted for impedance matching. A notch is used with a feed gap G to match the impedance to the high-speed connector, which in turn is set by the wire diameter pitch and lattice of the edge card connector pins. Tabs 50 are printed on the radiator board 30 which enables a tight plug-in to the edge card connector 90 via connector pins (see, for example, connector pins 55 in
Referring now to
The backplane PCB wiring 80 may possibly contain a balun. Any type of planar balun can be used, or no balun at all. Baluns provide wider bandwidth and can be integrated as part of the backplane (ground plane for antenna) mating board. The Hybrid Ring, or 180 delay line are examples. Tabs 50 can be printed in pairs, on the front side of the radiator board 30, back side, or both, and connected to the backplane board 70 through the edge card connector 90 and driven by an unbalanced to balanced balun excitation that can be designed by those knowledgeable in the state of the art (see, for example, Lewis, U.S. Pat. No. 2,639,325, issued May 19, 1953).
A flare for wideband operation can be designed by those knowledgeable in the art (see, for example, Lee et al. cited above) with the requirement that the flare taper be modified to match to the balun impedance and the parasitic reactance and impedance of the connector pins. The shape of the taper is modified, for example, slightly different compared to the Wideband flare with Klopfenstein taper, to optimize the impedance match with the reactance of the connector pins.
Referring now to
In general, each tab can make connection to 1, 2, or 3 or more pins depending on the impedance matching requirements, bandwidth, and assembly tolerance considerations. In addition, more than one radiator can be printed on a radiator board for an array antenna. Further, more than one radiator can plug into an edge card connector, depending on the array lattice.
To summarize, the plug-in antenna offers a low cost antenna assembly solution, using PCBs and edge card connectors compatible with a pick and place process, allowing such antennas to be efficiently produced in mass quantities. Plug-in antennas are compatible with a wide variety of commercially available edge card connectors. Antenna elements can be impedance matched to edge card connectors over a broad band of frequency range. Antenna elements can be arrayed and plugged into a backplane for high gain, and/or for electronically steered array applications.
Although certain exemplary embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims, and equivalents thereof.
