The present disclosure relates to wireless communications, and more particularly, to antenna systems and methods for wireless communications.
Cellular networks operating at 4G, and Wireless Local Area Networks (WLANs), are in abundant use and have recently evolved to provide moderate to high data-rate transmissions along with voice communications in a stable and reliable network over large regions and throughout urban areas. Mobile user devices, such as cellular phones and tablets, have progressed to a point of providing not only voice communications and low data-rate text and email service, but also high data-rate internet connectivity. The next evolutionary step in mobile and high data-rate communication systems is the transition to 5G protocol and networks. 5G networks can provide substantially higher data-rates and lower latency, and can be applicable for voice, data, and Internet of Things (IoT) applications. In addition, millimeter wave (mmWave) spectrum has been opened up for use to allow for larger instantaneous bandwidth to support higher data-rates. These mmWave bands, along with the sub-6 GHz bands currently used for 4G cellular and WLAN applications, may be used with 5G systems.
One example aspect of the present disclosure is directed to an antenna system for use in a wireless device having a periphery associated therewith. The antenna system includes a first antenna array include a plurality of antenna elements. The antenna system includes a second antenna array including a plurality of antenna elements. The first and second antenna arrays are each disposed about the periphery of the wireless device. At least one of the first and second antenna arrays is an adaptive antenna array having an active multi-mode antenna. The active multimode antenna can be adapted for configuration in one of a plurality of possible modes. The active multi-mode antenna is associated with a distinct radiation pattern when configured in each of the plurality of possible modes.
For purposes herein, the term “wireless device” includes any device capable of communication over a wireless network or wireless communication link. A “mobile wireless device” refers to a device capable of communicating over a wireless network or wireless communication link that is capable of being carried by hand of a user during operation. Example mobile wireless devices include smartphones, cellular phones, tablets, wearable devices, PDAs, electronic readers, and the like. The term “periphery” as used herein includes the outer limits or edge of a planar area of a wireless device. An “antenna array” refers to a plurality of antennas operating together. An “array pattern” refers to a radiation pattern associated with an antenna array. An array pattern can also be referred to as an array beam for the antenna array. An “adaptive antenna array” refers to an antenna array with one or more multi-mode antennas that can be controlled to adjust the array pattern associated with the antenna array.
Example aspects of the present disclosure are directed to an adaptive antenna array technique applicable to small form factor wireless devices (e.g., mobile wireless devices) where dynamic control of the antennas of the array is implemented to improve antenna system performance. Dynamic control of the radiation mode of the antenna elements forming array can be used to improve gain for the intended communication link, mitigate interference from non-intended sources, and/or improve communication link reliability by bringing antenna pattern and polarization diversity to the mobile antenna system.
In some embodiments, an antenna system includes an array having one or more active multi-mode antennas (also termed “modal antennas”). In some aspects several antenna arrays can be integrated into a wireless device and coverage of these antenna arrays can be coordinated to provide seamless communication system coverage as the device is rotated or re-positioned. For higher frequency communication systems (e.g., mmWave systems) multiple antenna arrays can be integrated into a wireless device (e.g., a mobile wireless device) to provide full angular coverage around the device. A beam steering methodology along with a hand-off methodology between the multiple arrays can be used for increased performance during system operation.
In some embodiments, a multi-mode antenna can be a single port antenna system capable of generating multiple radiation pattern modes, wherein the radiation pattern modes are de-correlated when compared to each other. Arraying a plurality of multi-mode antennas together can result in an array that has a substantially larger number of individual beam states compared to an antenna array formed from single radiation mode antenna elements, such as passive antennas. The multiple radiation patterns generated by the multi-mode antennas can be used to form a plurality of different array radiation patterns for the wireless device. The multi-mode antennas can be used to form and control the location of nulls and/or lobes in the array radiation pattern. The nulls can be positioned to provide interference suppression from RF interferers, for example, by steering a null in a direction of the interferer.
In some embodiments, each multi-mode antenna in the array can be connected to a front-end module (FEM). The FEM can include a power amplifier (PA) and low noise amplifier (LNA). The FEM can interface with one or more processors to control the multi-mode antennas to provide an adaptive array. The adaptive array implementation along with multi-mode antennas used to populate the elements of the array can provide a high degree of flexibility in terms of forming a beam and forming nulls in the array radiation pattern.
In some embodiments, one or multiple linear arrays are positioned on or near the periphery of a wireless communication device, such as a mobile wireless communication device. These arrays can include multiple antenna elements. One or more of the elements can be a multi-mode antenna capable of generating one of multiple radiation patterns from a plurality of possible modes.
A FEM can be connected to each element of the array or a number of elements in the array, allowing for the configuration of an adaptive array. This linear array configuration provides array pattern generation and control in one plane, with a wide beam width pattern in a second plane distinct from the device plane. The second plane can be but is not always orthogonal to the plane of the array. A control routine (e.g., an algorithm) can be configured for execution by one or more processors (e.g., a central processing unit (CPU)) within or coupled to the wireless device to form and position a main beam from the adaptive array to increase communication link performance (e.g., increase gain, mitigate interference, etc.). In some embodiments, the control routine can be configured to control the other arrays integrated into the device and coordinate hand-off of the antenna system function from one array to another.
In some embodiments, one or multiple two-dimensional (2D) arrays are positioned on a wireless device, such as a mobile wireless device. The array configuration can be of the type such that a linear array is positioned along the periphery of the device and additional rows of elements are positioned on or near the front or rear surface of the device. The 2D array configuration provides the capability of scanning the array main beam in multiple planes, allowing control of the beam in azimuth and elevation. A control routine can be configured to form and position a main beam (e.g., lobe) from the adaptive array to increase communication link performance (e.g., increase gain, mitigate interference). Additionally, the control routine can control the other arrays integrated into the device and coordinate hand-off of the antenna system function from one array to another.
In some embodiments, the control routine can access or obtain one or multiple signal quality metrics from one or more processors (e.g., a baseband processor). The control routine can uses these metrics to make array pattern steering decisions. The metric(s) can include a channel quality indicator (CQI), receive signal strength indicator (RSSI), Signal to Interference plus Noise Ratio (SINR), bit error rate (BER), data rate, other metric(s), or a combination of any of the foregoing, that provide information regarding the propagation channel and/or communication system performance. The one or more processors can include a baseband processor, application processor, or other processor resident in the communication system or connected to the communication system. The control routine can provide control signal settings to the multi-mode antennas to alter the antenna mode and array radiation pattern based on the metrics.
In some embodiments, the control routine can be configured to specifically determine multi-mode antenna array pattern states that reduce interference in the communication system connected to the multi-mode antenna array from sources such as communication systems or other sources of RF transmission in the field of view of the multi-mode antenna array. In some implementations, the control routine can use the CQI, RSSI, and/or SINR to model the propagation channel for each of the available possible radiation pattern of each antenna array. With the propagation channel modeled for each available possible array beam combination, the control routine can predict which radiation pattern, among the multiple radiation patterns of adaptive antenna array, will provide the best performances and/or improved performances for the next data communication exchange. Especially, if the SINR metric is being maximized, near maximized, or increased by the control routine, the level of interferences can be taken into account and the radiation pattern chosen can be radiation pattern that provides a good communication link with the intended transceiver and/or reduces interference from undesired RF sources.
In some embodiments, the control routine can control hand-off of the antenna system duties from one array to another array on the wireless communication device. In some implementations, the control routine can use the CQI, RSSI, and/or SINR to model the propagation channel for each of the available possible antenna array beam combinations. With the propagation channel modeled for each available possible radiation pattern beam combination and for each antenna array, it the control routine can predict which radiation pattern, among the multiple radiation patterns of the adaptive antenna array and among all arrays, can provide the best performances for the next data communication exchange. For instance, the control routine can predict when a current radiation pattern for a first combination of antenna arrays will deliver less performances than the radiation pattern combination for a second combination of antenna arrays. A threshold delta (difference) in signal quality or performance can be set. An appropriate array can be selected for use when handing off to the array would cause a delta in signal quality or performance that meets the threshold./ Active multi-mode antennas in the array, or a plurality of arrays, are each configured for increased performance across the mode set of respective multi-mode antennas to improve the hand-off process. For instance, the modes can be selected to reduce the time required for hand-off by increasing the delta in signal qualities between arrays.
In some embodiments, multi-mode antennas can be configured to operate as a hybrid array, wherein one FEM can be connected to two or more multi-mode antennas. The two or more multi-mode antennas can be operated as a sub-array and beam-steering coefficients can be determined to drive the grouping of two or more multi-mode antennas in the hybrid array. The modes of each multi-mode antenna can be surveyed and a mode that provides increased communication link performance can be selected.
In some embodiments, the array pattern can be adjusted according to device use case, such as to correct for hand and head loading, or device orientation. For instance, when the control routine does not rely on channel modelization and prediction to anticipate what is the best radiation pattern beam combination among all possibilities and among all antenna arrays, a deterministic approach can be used. In that deterministic approach, the radiation pattern can be chosen among the different possible radiation pattern of each array and among the different antenna arrays, based on sensor information. Look up tables, storing the performances of the different possible radiation pattern, of the different antenna arrays, versus different use cases, including device orientation, impact of the head, hand, can be used.
Device use case, such as hand and head loading, can be determined in a variety of manners, such as using one or more proximity sensors, accelerometers, or other motion sensors. One or more processors can received signals from the sensors and can implement a control routine to determine a use case of the device based on the signals. The one or more processors can then determine a mode of operation of one or more of the active multi-mode antennas in the system based at least in part on the use case of the wireless device.
One example embodiment of the present disclosure is directed to an antenna system for use in a wireless device having a periphery associated therewith. The antenna system includes a first antenna array including a plurality of first antennas. The antenna system includes a second antenna array including a plurality of second antennas. The first and second antenna arrays are each disposed about the periphery of the wireless device. At least one of the first and second antenna arrays is an adaptive antenna array including an active multi-mode antenna. The active multi-mode antenna can have a single feed port. The active multi-mode antenna can be adapted for configuration in one of a plurality of possible modes. The active multi-mode antenna can be associated with a distinct radiation pattern when configured in each of the plurality of possible modes.
In some embodiments, each of the first and second antenna arrays is an adaptive antenna array including an active multi-mode antenna. The active multi-mode antenna can have a single feed port. The active multi-mode antenna can be adapted for configuration in one of a plurality of possible modes. The active multi-mode antenna can be associated with a distinct radiation pattern when configured in each of the plurality of possible modes.
In some embodiments, the adaptive antenna array is coupled to one or more processors (e.g., via a FEM or other intervening elements). The one or more processors can be configured to execute control routine (e.g., by executing computer-readable instructions stored in one or more memory devices) to implement a control routine. In some embodiments, the control routine is operable to control the mode of the active multi-mode antenna to position a main beam of an array radiation pattern of the adaptive antenna array. For instance, the control routine can be operable to control the mode of the active multi-mode antenna based at least in part on one or more signal quality metrics (e.g., CQI, RSSI, SINR, etc.). In some embodiments, the one or more processors are configured to execute a control routine operable to coordinate handoff between the first antenna array and the second antenna array.
In some embodiments, the one or more processors are in communication with one or more sensors. The one or more processors can be operable to determine a use case for the wireless device based at least in part on the one or more sensors. The one or more processors can be configured to execute a control routine to control the adaptive antenna array based at least in part on the use case. In some embodiments, the adaptive antenna array is configured for beam pointing (e.g., steering of the main lobe of the antenna array) within the plane of the wireless device.
In some embodiments, the adaptive antenna array is arranged on a substrate having a first side and a second side that intersect each other at a junction. In some implementations, the active multi-mode antenna can be arranged on one of the first side or the second side. In some implementations, the active multi-mode antenna can include a first active multi-mode antenna arranged on the first side and a second active multi-mode antenna arranged on the second side. In some embodiments, the adaptive antenna array is arranged on an annular structure.
In some embodiments, the antenna system includes one or more multi-face antennas disposed on a planar surface within the periphery of the wireless device. The planar surface can be a front planar surface or a rear planar surface of the wireless device. In some embodiments, a distance between each of the first antennas and each of the second antennas is a distance between λ, and λ/4. λ is a wavelength associated with a frequency of operation of the first antennas and the second antennas.
Another example embodiment of the present disclosure is directed to an antenna system for use in a wireless communication device having a periphery. The antenna system includes a first adaptive antenna array having a plurality of first antenna elements disposed on the periphery of the wireless communication device. The first adaptive antenna array includes a first active multi-mode antenna being adapted for configuration in one of a plurality of possible modes. The first active multi-mode antenna is associated with a distinct radiation pattern when configured in each of the plurality of possible modes. The first adaptive antenna array is associated with a first array pattern. The system includes a second adaptive antenna array having a plurality of second antenna elements disposed on the periphery of the wireless communication device. The second adaptive antenna array includes a second active multi-mode antenna being adapted for configuration in one of a plurality of possible modes. The second active multi-mode antenna is associated with a distinct radiation pattern when configured in each of the plurality of possible modes. The second adaptive antenna array is associated with a second array pattern. The system includes one or more processors configured to execute a control routine operable to control the first adaptive antenna and the second adaptive antenna to control the first array pattern and the second array pattern. In some embodiments, the control routine is operable to control the first adaptive antenna and the second adaptive antenna for beam pointing about an azimuth associated with the wireless communication device.
In some embodiments, the antenna system includes a third adaptive antenna array located on a planar surface of the wireless communication device. The third adaptive antenna array includes a third active multi-mode antenna being adapted for configuration in one of a plurality of possible modes. The third active multi-mode antenna is associated with a distinct radiation pattern when configured in each of the plurality of possible modes. The third adaptive antenna array is associated with a third array pattern. In some embodiments, the control routine can be operable to control the first adaptive antenna array, the second adaptive antenna array, and the third adaptive antenna array for azimuth beam control and elevation beam control for the wireless device.
In some embodiments, the control routine is operable to control the first adaptive antenna array and the second adaptive antenna array based on a use case of the wireless communication device. The use case can be determined based at least in part on one or more signals from a sensor (e.g., proximity sensor, accelerometer, etc.) located on the wireless communication device.
With reference now to the FIGS., example embodiments will now be set forth.
Examples of active multi-mode antennas, also referred to as “modal antennas” or “null steering antennas”, are described in commonly owned U.S. Pat. No. 9,748,637; U.S. Pat. No. 9,240,634; U.S. Pat. No. 8,648,755; U.S. Pat. No. 8,362,962; and U.S. Pat. No. 7,911,402; the contents of each of which is hereby incorporated by reference. Example active multi-mode antennas are described with reference to
At any given frequency there can be a need to steer the array pattern (beam) of an antenna array. When the array surface is flat, conventional techniques often employ a set of antenna elements with finite spacings therebetween. However, when the surface is an odd-shape (not flat) like many IOT devices, cellphones, and other devices, a different technique can be required to achieve beam steering.
Although illustrative examples are provided in
A multi-frequency structure can include a set of active multi-mode antennas at a higher frequency within the lower frequency antennas (shared structure antennas). Distribution could be accomplished through a set of corporate feeds through the rear-side housing or cover. Mechanically, the feed could be either a contact from below, such as a spring connector, or a capacitive coupling component.
Additional features and benefits of the various embodiments may include:
adaptive antenna arrays may be implemented in one or more corners of a wireless device periphery;
modes for the active multi-mode antennas are each selected to include on of: vertical polarization, horizontal polarization, +45 degree and −45 degree polarization states to allow for dynamic control of polarization properties of the array beam;
an algorithm or control routine can be implemented to control the plurality of arrays in the wireless device to pass or hand off beam forming responsibility from one array to another as device orientation and/or position changes;
one or multiple of the arrays can be adaptive antenna arrays, wherein digital beamforming techniques are applied;
beam select modes can be designed into the arrays and control routine can provide an omni-directional mode for searching and selecting pilot signals or signaling required for an initialization phase prior to communicating with a node such as an access point;
the adaptive antenna arrays may be implemented at mmWave frequencies for use in 5G systems;
at lower frequency bands a reduced number of elements can be integrated into the device to provide a phased array, adaptive array, or hybrid array; and
as arrays are corrupted by use cases such as, hand-loading of a smartphone, hand and head loading, among others, the modes of operation of the multi-mode antennas can be controlled to compensate for the use case.
Thus, in some embodiments, multiple antenna arrays can be integrated into a wireless communication device and active multi-mode antenna elements can be used to populate some or all antenna elements in the arrays to provide full coverage and connectivity for the radio in the communication device. An algorithm or control routine can be configured to form and position a main beam from the adaptive arrays to optimize for a communication link. Additionally, the control routine can control and coordinate hand-off of the antenna system function used for communications from one array to another. Array beam positions can be selected to increase communication link effective radiated power (EIRP) or for interference suppression. The arrays can be configured along with the control routine to provide continuous beam positioning for a wireless device where orientation and position are dynamically changing. This configuration of multiple arrays is applicable for mmWave applications as well as sub-6 GHz applications such as LTE communications.
As previously discussed, the various embodiments illustrated in
While the present subject matter has been described in detail with respect to specific example embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art.
This application claims benefit of priority with U.S. Provisional Application Ser. No. 62/476,640, filed Mar. 24, 2017; and further claims benefit of priority with U.S. Provisional Application Ser. No. 62/522,109, filed Jun. 20, 2017; the contents of each of which are hereby incorporated by reference.
Number | Date | Country | |
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62522109 | Jun 2017 | US | |
62476640 | Mar 2017 | US |