Patent Description:
<CIT> discloses an antenna system capable of transmitting electromagnetic radiation.

<CIT> discloses an aerial device applied to an electronic apparatus and a method for setting the aerial device.

The document <CIT> discloses an antenna arrangement comprising at least two conductive sheets arranged around at least one ground plane.

<CIT> discloses an antenna device that can receive both of vertically and horizontally polarized waves.

The object of the invention is to provide enhanced antenna performance.

The described technology provides antenna polarization diversity to enhance the MIMO performance of multiple antennas, especially when the multiple antennas do not exhibit significant placement diversity. An antenna assembly provides selectable antenna polarization in the antenna assembly on a ground plane. An antenna element of the antenna assembly drives a first electrical configuration with a radiofrequency signal to radiate with a polarization predominately in a first direction of propagation. The antenna assembly is selectively modified from the first electrical configuration to a second electrical configuration, responsive to driving the antenna element of the antenna assembly in the first electrical configuration. The antenna element of the antenna assembly is driving in the second electrical configuration with the radiofrequency signal to radiate with a polarization predominately in a second direction of propagation, responsive to selectively modifying the antenna assembly from the first electrical configuration to the second electrical configuration. The antenna element includes a loop antenna, formed at least in part from a corner notch in the ground plane.

As mobile communication devices continue to get smaller and signaling protocols push for smaller and more-tightly packed antennas (e.g., in dense antenna arrays), antenna separation diversity becomes less feasible. For example, in a <NUM> antenna array, the individual antennas may be packed tightly together, offering little separation among them. Moreover, the real estate available to antennas in the pursuit of smaller devices and smaller display bezels puts additional limitations on antenna separation diversity. Accordingly, these constraints limit the benefits of MIMO performance enhancements.

The described technology provides a communications device capable of dynamically switching the radiofrequency polarization of individual antennas through hardware and/or software control, thereby providing polarization diversity for individual antennas to obtain MIMO performance enhancements, even for antennas with minimal separate diversity.

<FIG> illustrates an example computing device <NUM> having an antenna assembly (not shown in <FIG>) at each of two corners, wherein the antenna assemblies radiate with polarization predominately in the theta (Θ) axis of polarization (e.g., in a direction of propagation). As shown in <FIG>, the theta axis extends from top to bottom in the illustrated computing device <NUM> and is orthogonal to a phi (Φ) axis extended laterally from side to side in the illustrated computing device <NUM>. It should be understood that the theta and phi axes are examples of first and second directions of propagation of linear polarization and ground plane current flow, although other directions may also be employed. In various implementations, the first and second directions of propagation may be orthogonal or substantially orthogonal (e.g., within ±<NUM>°, ±<NUM>°, ±<NUM>°).

The computing device <NUM> includes a display <NUM>, a bezel section <NUM> positioned about the display <NUM>, and various electronic and mechanical components within the computing device case <NUM>, which is at least partially include a metal or metallic enclosure, although other implementations may be made from other materials. The computing device <NUM> includes radiofrequency transmitters and receivers, including antenna assemblies at the top corners of the computing device <NUM>, although the placement of antenna assemblies may vary in other implementations.

The dashed contour lines located at each top corner of the computing device <NUM> represent electric field lines <NUM> and <NUM> associated with antenna assemblies at each corner. An antenna assembly includes a transducer that converts radiofrequency electric field current into electromagnetic radiofrequency waves that are radiated into the space around the antenna assembly. The electric field plane determines the polarization or orientation of the electromagnetic radiofrequency waves radiated from the antenna assembly. A linear polarized antenna element of an antenna assembly radiates predominately in one plane along a direction of propagation.

The computing device <NUM> includes antenna assemblies with switchable electrical configurations, wherein different electrical configurations produce electromagnetic radiofrequency waves that radiate into space predominately in different directions of propagation. Accordingly, in <FIG>, the electrical configuration of the antenna assembly, as shown later in <FIG>, induces electromagnetic radiofrequency waves that radiate into space a polarization predominately in the theta direction of propagation, which is illustrated by the arrows <NUM> and <NUM> indicated greater propagation along the theta direction of propagation than in any other direction.

<FIG> illustrates an example computing device <NUM> having an antenna assembly (not shown in <FIG>) at each of two corners, wherein the antenna assemblies radiate with polarization predominately in the phi axis of polarization (e.g., in a direction of propagation). As shown in <FIG>, the phi axis extends from laterally from side-to-side in the illustrated computing device <NUM> and is orthogonal to a theta axis extended from top to bottom in the illustrated computing device <NUM>. It should be understood that the theta and phi axes are examples of first and second directions of propagation of linear polarization and ground plane current flow, although other directions may also be employed. In various implementations, the first and second directions of propagation may be orthogonal or substantially orthogonal (e.g., within ±<NUM>°, ±<NUM>°, ±<NUM>°).

The computing device <NUM> includes antenna assemblies with switchable electrical configurations, wherein different electrical configurations produce electromagnetic radiofrequency waves that radiate into space predominately in different directions of propagation. Accordingly, in <FIG>, the electrical configuration of the antenna assembly, as shown later in <FIG>, induces electromagnetic radiofrequency waves that radiate into space a polarization predominately in the phi direction of propagation, which is illustrated by the arrows <NUM> and <NUM> indicated greater propagation along the phi direction of propagation than in any other direction.

<FIG> illustrates an example computing device <NUM> having antenna assemblies <NUM> and <NUM> for providing antenna polarization diversity. In the illustrated implementation, the computing device <NUM> includes a ground plane <NUM> with corner apertures <NUM> and <NUM> (e.g., notches or holes), each corner aperture forming at least a portion of an antenna element. For example, the antenna element can be created from a closed hole cut or otherwise formed into the corner of the ground plane <NUM>, such that the boundaries of the closed hole are part of the ground plane <NUM>. In another implementation, the antenna element can be created from an open notch cut or otherwise formed in the corner of the ground plane <NUM> with a conductive connector or routing connecting the two outer corners of the notch (e.g., so as to close the loop of a loop antenna), such that some of the boundaries of the resulting aperture are part of the ground plane <NUM> and other boundaries include one or more separate conductive paths. Other implementations may also be employed.

Each of the illustrated antenna elements forms a loop antenna having notched edges of the ground plane <NUM> as two segments of the loop, with different segments of the loop tied to ground through a switched path. The combination of multiple loop segments forms a loop antenna for each antenna assembly. A radiofrequency feed (e.g., radiofrequency feeds <NUM> and <NUM>) is coupled to drive each corresponding antenna element with a radiofrequency signal. Each antenna element is connected to ground via two switched connecting paths of the corner aperture. The switched connecting paths of the antenna assemblies <NUM> and <NUM> are controlled by a polarization switch controller <NUM>, which alternately switches between a theta polarization and a phi polarization in each antenna assembly. The polarization switch controller <NUM> may be controlled via hardware and/or software (e.g., antenna firmware).

A blowout rendering of the left antenna assembly <NUM> is shown at blowout <NUM>, although the structural and functional details described with regard to the blowout <NUM> can apply to either antenna assembly. In the illustrated embodiment, ground plane edges <NUM> and <NUM> form two segments of the loop antenna element, with conductive connectors forming additional segments <NUM> and <NUM> between the ground plane notch corners. Each ground plane notch corner is connected to ground through switched connecting paths <NUM> and <NUM>. The switched connecting path <NUM> includes a shorted connector path <NUM> and a capacitor path <NUM>, between which a selector (e.g., a switch <NUM>) selects one path or the other. The switched connecting path <NUM> includes a shorted connector path <NUM> and a capacitor path <NUM>, between which a selector (e.g., a switch <NUM>) selects one path or the other. It should be understood that multiple capacitor paths with different capacitance values may also be implemented using similar selector circuits.

A feed line <NUM> electrically drives the loop antenna from the radiofrequency feed <NUM>. The control lines <NUM> and <NUM> control the switches <NUM> and <NUM> respectively from the polarization switch controller <NUM>. When the switches <NUM> and <NUM> are switched to connect the top segment of the loop antenna through the capacitor path <NUM> to ground and the side segment of the loop antenna through the shorted connector path <NUM> to ground, radiofrequency electric field current from the radiofrequency feed <NUM> is induced predominately in the phi direction of current propagation in the ground plane, thereby inducing a predominately theta axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>). When the switches <NUM> and <NUM> are switched to connect the side segment of the loop antenna through the capacitor path <NUM> to ground and the top segment of the loop antenna through the shorted connector path <NUM> to ground, radiofrequency electric field current from the radiofrequency feed <NUM> is induced predominately in the theta direction of current propagation in the ground plane, thereby inducing a predominately phi axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>).

<FIG> illustrates an example computing device <NUM> having antenna assemblies <NUM> and <NUM> configured to provide polarization predominately in the theta axis of polarization. When the antennas assemblies <NUM> and <NUM> are switched to connect the top segment of the loop antennas through the capacitor path to ground and the side segment of the loop antenna through the shorted connector paths to ground, radiofrequency electric field current from the radiofrequency feed is induced predominately (as illustrated by the larger phi arrow <NUM> as compared to the smaller theta arrow <NUM>) in the phi direction of current propagation in the ground plane <NUM>, thereby inducing a predominately theta axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>).

<FIG> illustrates an example computing device <NUM> having antenna assemblies <NUM> and <NUM> configured to provide polarization predominately in the phi axis of polarization. When the antennas assemblies <NUM> and <NUM> are switched to connect the side segment of the loop antenna through the capacitor paths top ground and the top segment of the loop antenna through the shorted connector paths to ground, radiofrequency electric field current from the radiofrequency feed is induced predominately (as illustrated by the larger theta arrow <NUM> as compared to the smaller phi arrow <NUM>) in the theta direction of current propagation in the ground plane <NUM>, thereby inducing a predominately phi axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>).

<FIG> illustrates example operations <NUM> for providing antenna polarization diversity. A driving operation <NUM> drives an antenna element of an antenna assembly in a first electrical configuration with a radiofrequency signal to radiate with a polarization predominately in a first direction of propagation. For example, if the first electrical configuration connects the top segment of the loop antenna through the capacitor paths to ground and the side segment of the loop antenna through the shorted connector paths to ground, radiofrequency electric field current from the radiofrequency feed is induced predominately in the phi direction of current propagation in the ground plane, thereby inducing a predominately theta axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>). In contrast, if the first electrical configuration connects the side segment of the loop antenna through the capacitor paths to ground and the top segment of the loop antenna through the shorted connector paths to ground, radiofrequency electric field current from the radiofrequency feed is induced predominately in the theta direction of current propagation in the ground plane, thereby inducing a predominately phi axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>).

A selective modification operation <NUM> modifies the antenna assembly from the first electrical configuration to a second electrical configuration, such as controlled by a polarization switch controller connected to selectors. The selective modification operation <NUM> can be repeated between each electrical configuration to alternate antenna polarization.

Another driving operation <NUM> drives the antenna element of the antenna assembly in the second electrical configuration with the same radiofrequency signal to radiate with a polarization predominately in a second direction of propagation. For example, if the second electrical configuration connects the side segments of the loop antennas through the capacitor paths to ground and the top segments of the loop antennas through the shorted connector paths to ground, radiofrequency electric field current from the radiofrequency feed is induced predominately in the theta direction of current propagation in the ground plane, thereby inducing a predominately phi axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>). In contrast, if the second electrical configuration connects the top segments of the loop antennas through the capacitor paths to ground and the side segment of the loop antenna through the shorted connector paths to ground, radiofrequency electric field current from the radiofrequency feed is induced predominately in the phi direction of current propagation in the ground plane, thereby inducing a predominately theta axis polarization in the resulting electromagnetic radiofrequency (as shown in <FIG>).

<FIG> illustrates an example computing device for use in providing antenna polarization diversity. The computing device <NUM> may be a client device, such as a laptop, mobile device, desktop, tablet, or a server/cloud device. The computing device <NUM> includes one or more processor(s) <NUM>, and a memory <NUM>. The memory <NUM> generally includes both volatile memory (e.g., RAM) and non-volatile memory (e.g., flash memory). An operating system <NUM> resides in the memory <NUM> and is executed by the processor(s) <NUM>.

In an example computing device <NUM>, as shown in <FIG>, one or more modules or segments, such as antenna drivers <NUM>, application modules, and other modules, are loaded into the operating system <NUM> on the memory <NUM> and/or storage <NUM> and executed by processor(s) <NUM>. The storage <NUM> may be stored wireless communications parameters, drivers, and other data and be local to the computing device <NUM> or may be remote and communicatively connected to the computing device <NUM>.

The computing device <NUM> includes a power supply <NUM>, which is powered by one or more batteries or other power sources and which provides power to other components of the computing device <NUM>. The power supply <NUM> may also be connected to an external power source that overrides or recharges the built-in batteries or other power sources.

The computing device <NUM> may include one or more communication transceivers <NUM> which may be connected to one or more antenna(s) <NUM> to provide network connectivity (e.g., mobile phone network, Wi-Fi®, Bluetooth®) to one or more other servers and/or client devices (e.g., mobile devices, desktop computers, or laptop computers). The computing device <NUM> may further include a network adapter <NUM>, which is a type of communication device. The computing device <NUM> may use the adapter and any other types of communication devices for establishing connections over a wide-area network (WAN) or local-area network (LAN). It should be appreciated that the network connections shown are exemplary and that other communications devices and means for establishing a communications link between the computing device <NUM> and other devices may be used.

The computing device <NUM> may include one or more input devices <NUM> such that a user may enter commands and information (e.g., a keyboard or mouse). These and other input devices may be coupled to the server by one or more interfaces <NUM> such as a serial port interface, parallel port, or universal serial bus (USB). The computing device <NUM> may further include a display <NUM>, such as a touch screen display.

The computing device <NUM> may include a variety of tangible processor-readable storage media and intangible processor-readable communication signals. Tangible processor-readable storage can be embodied by any available media that can be accessed by the computing device <NUM> and includes both volatile and nonvolatile storage media, removable and non-removable storage media. Tangible processor-readable storage media excludes intangible communications signals and includes volatile and nonvolatile, removable and non-removable storage media implemented in any method or technology for storage of information such as processor-readable instructions, data structures, program modules or other data. Tangible processor-readable storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CDROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other tangible medium which can be used to store the desired information and which can be accessed by the computing device <NUM>. In contrast to tangible processor-readable storage media, intangible processor-readable communication signals may embody processor-readable instructions, data structures, program modules or other data resident in a modulated data signal, such as a carrier wave or other signal transport mechanism. By way of example, and not limitation, intangible communication signals include signals traveling through wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared, and other wireless media.

Some implementations may comprise an article of manufacture. An article of manufacture may comprise a tangible storage medium to store logic. Examples of a storage medium may include one or more types of computer-readable storage media capable of storing electronic data, including volatile memory or non-volatile memory, removable or non-removable memory, erasable or non-erasable memory, writeable or rewriteable memory, and so forth. Examples of the logic may include various software elements, such as software components, programs, applications, computer programs, application programs, system programs, machine programs, operating system software, middleware, firmware (including antenna firmware <NUM>), software modules, routines, subroutines, operation segments, methods, procedures, software interfaces, application program interfaces (API), instruction sets, computing code, computer code, code segments, computer code segments, words, values, symbols, or any combination thereof. In one implementation, for example, an article of manufacture may store executable computer program instructions that, when executed by a computer, cause the computer to perform methods and/or operations in accordance with the described embodiments. The executable computer program instructions may include any suitable type of code, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, and the like. The executable computer program instructions may be implemented according to a predefined computer language, manner or syntax, for instructing a computer to perform a certain operation segment. The instructions may be implemented using any suitable high-level, low-level, object-oriented, visual, compiled and/or interpreted programming language.

Claim 1:
A method of providing selectable antenna polarization in an antenna assembly (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) on a ground plane (<NUM>, <NUM>, <NUM>), the method comprising:
driving (<NUM>) an antenna element of the antenna assembly in a first electrical configuration with a radiofrequency signal to radiate with a polarization predominately in a first direction of propagation (<NUM>, <NUM>, <NUM>);
selectively (<NUM>) modifying the antenna assembly from the first electrical configuration to a second electrical configuration, responsive to driving the antenna element of the antenna assembly in the first electrical configuration; and
driving (<NUM>) the antenna element of the antenna assembly in the second electrical configuration with the radiofrequency signal to radiate with a polarization predominately in a second direction of propagation (<NUM>, <NUM>, <NUM>), responsive to selectively modifying the antenna assembly from the first electrical configuration to the second electrical configuration,
wherein the antenna element includes a loop antenna, formed at least in part from a corner notch (<NUM>, <NUM>) in the ground plane.