Patent Application
20190305431
The present disclosure relates generally to antenna systems or electronic devices with an antenna, and more particularly, antenna systems having conductive structures with one or more selective ground couplings.
Electronic devices, such as smartphones, are increasingly supporting more capabilities in instances where managing the overall size of the device is a concern. As part of an overall increase in capabilities, the electronic devices, such as smartphones, are increasingly being expected to support more types of communications and/or more extensive forms of existing types of communications, simultaneously or otherwise, which support an increasing number and breadth of frequencies and/or have communication conditions that provide for the inclusion of multiple detectable signal paths. Examples of communications being increasingly supported include cellular voice and data type communications, satellite GPS type communications, Bluetooth ad hoc peer to peer type communications, Wi-Fi wireless packet data type communications, etc. Examples of more extensive forms of existing types of communications include additional support for carrier aggregation, diversity, beamforming, and MIMO (multiple-input and multiple-output).
The increasing support of communications has resulted in a larger number of electromagnetic radiating/receiving elements being included as part of an antenna system, that needs to be accommodated in smaller and ever more crowded space, and/or radiating/receiving elements that can be tuned to function alternatively and/or simultaneously across multiple sets of frequencies.
The specific frequencies supported by a particular radiating/receiving structure is largely impacted by the electrical geometries, (i.e. size and shapes), associated with the conductive structure. The geometries which affect performance across one or more sets of frequencies can be impacted by an actual size or shape of the structure, or effective geometries, where types of materials and associated components may affect the apparent electrical geometries of the structure. In order for a radiating/receiving element to function alternatively and/or simultaneously across different sets of frequencies, the effective electrical geometries can be managed through the selective coupling of elements related to the radiating/receiving structures, which can result in better or worse tuning relative to each of one or more sets of frequencies.
Structure that might facilitate alternative geometries and the mechanisms for a selective adjustment between the different apparent electrical geometries can often require additional space within the device, where the available space is already a precious resource. As such, the present innovators have recognized that it would be beneficial to include some of the circuitry that can be selectively used to support the multiple possible apparent electrical geometries, as part of the structural housing, including the mechanical mounting structures used to support the inclusion of the electrical circuits into the overall structure of the device.
The present application provides an antenna system for use in an electronic device having wireless communication capabilities. The antenna system includes a conductive ground structure, and one or more arms. Each arm has two ends and a conductive path between the two ends. A first one of the two ends of the arm is coupled to the conductive ground structure, where from the first end and along the conductive path, the arm extends along a side edge of the conductive ground structure forming a slot, and continues beyond an end of the conductive ground structure a distance away from the conductive ground structure. The distance between the end of the conductive ground structure and the corresponding conductor path of the respective one of the one or more arms encompasses an area forming a loop which is internal to the antenna system. The antenna system further includes one or more bridge circuits on a circuit substrate. Each bridge circuit selectively electrically couples one of the one or more arms to the conductive ground structure across the corresponding slot, formed there between, at a respective point along the corresponding conductive path of the one of the one or more arms a distance away from the first one of the two ends of the one of the one or more arms that is coupled to the conductive ground structures. Each of the one or more bridge circuits are associated with a mechanical mounting structure for coupling at least one of the conductive ground structure or the one of the one or more arms to the circuit substrate.
In at least one embodiment, the selective electrical coupling of the one of the one or more arms to the conductive ground structure via the respective bridge circuit is used to selectively tune the one of the one or more arms for alternative use in radiating or receiving each of two different sets of electromagnetic signal frequencies.
In at least a further embodiment, the mechanical mounting structure includes a first mechanical mount, which couples the conductive ground structure to the circuit substrate, and a second mechanical mount, which couples the one of the one or more arms to the circuit substrate. In at least a still further embodiment, the conductive ground structure is included as part of the circuit substrate.
The present application further provides a wireless communication device, which includes a controller, a transceiver that is coupled to the controller, and an antenna system that is coupled to the transceiver. The antenna system has a conductive ground structure, and one or more arms. Each arm has two ends and a conductive path between the two ends. A first one of the two ends of the arm is coupled to the conductive ground structure, where from the first end and along the conductive path, the arm extends along a side edge of the conductive ground structure forming a slot, and continues beyond an end of the conductive ground structure a distance away from the conductive ground structure. The distance between the end of the conductive ground structure and the corresponding conductor path of the respective one of the one or more arms encompasses an area forming a loop which is internal to the antenna system. The antenna system further has one or more bridge circuits. Each bridge circuit selectively electrically couples one of the one or more arms to the conductive ground structure across the corresponding slot, formed there between, at a respective point along the corresponding conductive path of the one of the one or more arms a distance away from the first one of the two ends of the one of the one or more arms that is coupled to the conductive ground structures. Each of the one or more bridge circuits are associated with a mechanical mounting structure for coupling one of the conductive ground structure or the one of the one or more arms to a circuit substrate.
These and other features, and advantages of the present disclosure are evident from the following description of one or more preferred embodiments, with reference to the accompanying drawings.
While the present application is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described presently preferred embodiments with the understanding that the present disclosure is to be considered an exemplification and is not intended to limit the invention to the specific embodiments illustrated. One skilled in the art will hopefully appreciate that the elements in the drawings are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements with the intent to help improve understanding of the aspects of the embodiments being illustrated and described.
In the illustrated embodiment, the radio frequency cellular telephone includes a display 102 which covers a large portion of the front facing. In at least some instances, the display can incorporate a touch sensitive matrix, that can help facilitate the detection of one or more user inputs relative to at least some portions of the display, including an interaction with visual elements being presented to the user via the display 102. In some instances, the visual element could be an object with which the user can interact. In other instances, the visual element can form part of a visual representation of a keyboard including one or more virtual keys and/or one or more buttons with which the user can interact and/or select for a simulated actuation. In addition to one or more virtual user actuatable buttons or keys, the device 100 can include one or more physical user actuatable buttons 104. In the particular embodiment illustrated, the device has three such buttons located along the right side of the device.
The exemplary wireless communication device 100, illustrated in
While a particular peripheral communication interface is illustrated, one skilled in the art will appreciate that the peripheral communication interface can take alternative and/or still further forms via which data and/or power signals can be conveyed between a peripheral and a base device. In at least some instances, the structure that can support such an interface can include forms which are compatible with various industry standards, such as Universal Serial Bus (USB), Peripheral Component Interconnect Express (PCIE), Subscriber Identity Module (SIM), etc., type standards and/or interfaces.
In the particular embodiment illustrated, the back view has a rear housing portion 212, which can be comprised of a conductive material, which in at least the illustrated embodiment corresponding to at least some prior embodiments, does not extend the full length/height of the device. More specifically, the ends of the rear housing portion 212 stops short of both the top end 214 and the bottom end 216 of the device proximate the areas where multiple conductive arms 218 formed in an outer side band of the housing can extend around the areas forming one or more of the device corners, where the multiple conductive arms are each intended to function as an antenna. In at least some instances, the outer side band extends around the outer side perimeter of the device. By stopping short of the ends 214 and 216, a rear housing portion made of a conductive material can avoid extending into an area that might impact the performance of the multiple arms functioning as elements for radiating and/or receiving electromagnetic energy, such as an antenna.
The rear housing portion 212 being comprised of a conductive material can serve as and/or be a part of a conductive ground structure against which the signal traveling along a respective one of the arms can radiate. The conductive ground structure can also provide a return path for any currents associated with the wireless signaling. The distance that the respective arm extends beyond the corresponding end 214 or 216 helps serve to define an area corresponding to a loop that is internal to the antenna structure. While the conductive ground structure, in the illustrated embodiment, has been associated with an external housing surface, the conductive ground structure can also and/or alternatively be incorporated into other conductive elements, such as a circuit board substrate internal to the housing, a back side surface inlay or insert, and/or a housing for a secondary device or peripheral that might be coupled to the main device.
A more precise description of the path that the current follows includes a path that takes into account the respective slot 314 formed between an arm 218 and the conductive ground structure 301, which extends along a side edge 316 of the conductive ground structure 301, and continues beyond an end 318 of the conductive ground structure. In the illustrated embodiment, the right side slot has an overall physical slot length of L1, which can affect the length of the current path, which in turn can affect the ability of the arm 218 to receive/radiate a wireless signal at one or more frequencies. While the physical slot length is often generally fixed, an effective slot length or virtual slot length can be created through the selective coupling of the corresponding one of the one or more arms 218 to the conductive ground structure 301 at different points along the length of the arm. Different slot lengths will correspondingly be respectively better or worse for radiating/receiving wireless signals relative to different sets of frequencies. For example, in at least one embodiment, one particular slot length, such as a slot length of 40 millimeters, may be more suitable for ultra-low band and low band operation on the order of 700-960 MHz. An alternative slot length, such as a slot length of 20 millimeters, may be more suitable for mid-band operation on the order of 1700-2200 MHz.
A different apparent or virtual effective slot length L2 can be created via a bridge circuit 320, which can selectively electrically couple the conductive arm 218 to the conductive ground structure 301. By adjusting an apparent or virtual effective slot length of the slot, the particular sets of frequencies that the conductive arm 218 has an ability to radiate or receive can be made selectively better or worse. In essence, the arm can be selectively tuned/detuned for different sets of frequencies by alternatively configuring the operation of the structure including adjusting the respective apparent slot length, as desired. While a single bridge circuit 320 is illustrated in
The manner in which the bridge circuit couples to one or both of the conductive ground structure 301 and/or one of the one or more conductive arms 218 can impact the amount of space required for affecting the various connections. By incorporating an electrical connection as part of the mechanical mounting, a separate exclusively electrical coupling, and the associated space that would be used therewith, may be avoided.
While the embodiment illustrated in
In an alternative embodiment,
While in some instances the values of the various components could be selected so as to manage the nature of the coupling for each of the various frequencies. The bridge circuit 320 can in some instances incorporate some degree of active control, so as to produce the desired effect at each frequency and/or operating mode of interest. The bridge circuit 320 can include various passive elements, such as inductors, capacitor and resistors having fixed values. The bridge circuit 320 can also include various active element, such as the switch 904, and variable value elements, such as the variable capacitor 1010. The control of the active elements can be coordinated with the current desired wireless communication operating frequencies being used with the one or more radiating structures, such as the one or more conductive arms 218, so as to enable the radiating structures to continue to operate in a desired manner. In at least some instances, an ability to adjust the apparent slot length can be used to coordinate the use of low band signals with high band signals, and in other instances an ability to adjust the apparent slot length can be used to coordinate the use of ultra low band signals with mid band frequencies. Other combinations are further possible.
Management of the active elements can be through the use of a controller, that could be implemented in the form of one or more processors, which are capable of executing one or more sets of pre-stored instructions. The controller can additionally or alternatively include state machines and/or logic circuitry. Such a controller could be incorporated as part of the overall control of the device, or could be included as part of the structure specific to the wireless modem and/or one or more transceivers. Presumably, the controller would be aware of the desired operating mode and frequencies of the various forms of wireless communications that are currently being used, and would be able to adjust the operating characteristics of the bridge circuit and included selective electrical coupler, accordingly.
The various passive elements forming the bridge circuit could be in the form of a lumped element, such as a lumped capacitor or a lumped inductor, such as a separate discrete component. The various elements could alternatively include distributed elements, such as a distributed capacitor. In some instances, the distributed element can be incorporated into the structure of the circuit substrate.
While the preferred embodiments have been illustrated and described, it is to be understood that the invention is not so limited. Numerous modifications, changes, variations, substitutions and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims.
