Electronically steerable antenna array

Abstract

The present disclosure provides an electronically steerable and switchable antenna array. The antenna array can: produce a first beam having a first coverage and a second beam having a second coverage by selecting one of a first beamwidth and a second beamwidth for the first beam and the second beam; responsive to selecting the first beamwidth: switch a signal input to a narrow beam antenna array; steer the first beam to one of a first positive, negative, or zero offset position; independently steer the second beam to one of a second positive, negative, or zero offset position; transmit a signal received from the signal input via the first beam and the second beam; and responsive to selecting the second beamwidth: switch the signal input to a wide beam antenna array; and transmit a signal received from the signal input via the first beam and the second beam.

Description

[0001] Cross-reference to related applications

[0002] This disclosure claims priority and benefit to U.S. Provisional Patent Application Serial No. 62 / 931,583, filed November 6, 2019, which is incorporated herein by reference in its entirety. Technical Field

[0003] The embodiments presented in this disclosure generally relate to antennas. More specifically, the embodiments disclosed herein relate to antenna arrays that provide a variety of controllable coverage patterns and low interference to adjacent devices. Background Technology

[0004] As wireless communication options become available in more locations and more users utilize the provided wireless communication services, the demand for bandwidth and the potential for interference are both increasing. In large venues such as stadiums, theaters, gymnasiums, and parks, there may be large open spaces between access points (APs) providing wireless communication services and stations (STAs) that rely on access points for network connectivity. Unimpeded signal propagation in open spaces can lead to low inter-cell cross-attenuation and exacerbate interference within the network, as network operation is limited in how different channels can be reused; free spectrum becomes increasingly important. Attached Figure Description

[0005] To gain a more detailed understanding of the features described above, the present disclosure, which has been briefly summarized above, can be described in more detail with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate typical embodiments and should not be considered limiting; other equally effective embodiments are also considered.

[0006] Figure 1A and Figure 1B The coverage of an antenna array including a wide beam array is shown according to an embodiment of the present disclosure.

[0007] Figures 2A-2F The coverage of an antenna array including a steerable narrow beam array is shown according to an embodiment of the present disclosure.

[0008] Figure 3A and Figure 3B The overlap of the first wide coverage area of ​​the first wide beam array and the coverage area of ​​the first narrow beam array according to an embodiment of the present disclosure is shown.

[0009] Figure 4A and Figure 4B The turning position and offset of a narrow beam array according to an embodiment of the present disclosure are shown.

[0010] Figure 5 An antenna segment component layout according to an embodiment of the present disclosure is shown.

[0011] Figure 6 The component layout of an antenna array according to an embodiment of the present disclosure is shown.

[0012] Figure 7 This is a flowchart of a method for managing an electronically steerable antenna array according to embodiments of the present disclosure.

[0013] Figure 8 Hardware for a computing device that can be used in the AP described in this disclosure is shown.

[0014] For ease of understanding, the same reference numerals are used to identify the same elements in the drawings where possible. It is contemplated that elements disclosed in one embodiment may be advantageously used in other embodiments without specific description. Detailed Implementation

[0015] Overview

[0016] One embodiment presented in this disclosure is an apparatus comprising: a plurality of antenna segments, each antenna segment comprising: a narrow-beam antenna array configured to generate a first beam having a first beamwidth; a wide-beam antenna array configured to generate a second beam having a second beamwidth greater than the first beamwidth of the first beam; a switching path configured to selectively activate one of the narrow-beam antenna array or the wide-beam antenna array at a given time; and a first phase shifter and a second phase shifter connected between the switching path and the narrow-beam antenna array. The device is configured to redirect the first beam from a first position to a second position in an azimuth plane; wherein, when a given first beam of a given antenna segment of the plurality of antenna segments is redirected to the first position and a different first beam of a different antenna segment of the plurality of antenna segments is redirected to the first position, the corresponding coverage areas of the given first beam and the different first beam overlap; and wherein, when the given first beam is redirected to the second position and the different first beam is redirected to the second position, the corresponding coverage areas of the given first beam and the different first beam are spatially isolated from each other.

[0017] One embodiment presented in this disclosure is a system comprising: a steerable and switchable antenna array configured to generate a first beam having a first coverage area and a second beam having a second coverage area; a processor; and a memory storing instructions that, when executed by the processor, cause the steerable and switchable antenna array to perform the following operations: selecting one of a first beamwidth and a second beamwidth for both the first beam and the second beam; in response to selecting the first beamwidth: switching a signal input to a narrow-beam antenna array included in the steerable and switchable antenna array; steer the first beam to one of a first positive offset, a first negative offset, and a first neutral position; steer the second beam to one of a second positive offset, a second negative offset, and a second neutral position; and transmitting a signal received from the signal input via the first beam and the second beam; and in response to selecting the second beamwidth: switching the signal input to a wide-beam antenna array included in the steerable and switchable antenna array; and transmitting a signal received from the signal input via the first beam and the second beam.

[0018] One embodiment presented in this disclosure is a method comprising: forming a first beam having a first coverage area via a first antenna segment, wherein forming the first beam comprises: reducing a first amplitude of the first beam by providing lower power to external elements of a first antenna array than to internal elements of the first antenna array; and shifting the first beam from a first neutral position to one of a first positive offset and a first negative offset by a phase shift signal to transmit according to the first beam on a column of the first antenna array; and forming a second beam having a second coverage area via a second antenna segment, wherein forming the second beam comprises: providing lower power to external elements of the second antenna array than to internal elements of the second antenna array. The power is used to gradually reduce the second amplitude of the second beam; and the second beam is redirected from a second neutral position to one of a second positive offset and a second negative offset by a phase shift signal, so as to transmit according to the second beam on the column of the second antenna array; wherein, when the first beam is redirected to the first positive offset and the second beam is redirected to the second negative offset, the first coverage area and the second coverage area form a line-of-sight pattern; and wherein, when the first beam is redirected to the first negative offset and the second beam is redirected to the second positive offset, the first coverage area and the second coverage area form an extended linear pattern with spatial isolation between the first coverage area and the second coverage area.

[0019] Example Implementation

[0020] This disclosure provides an electronically switchable, beam-steerable antenna array with ultra-low sidelobes. The antennas can be packaged together with AP control hardware in a single weatherproof enclosure for deployment in various locations, including enclosed, semi-enclosed, or open spaces. These arrays are capable of switching from various beamwidths and are electronically steerable in a beamwidth setting (i.e., the antenna remains stationary, but the direction of the main beam projection changes). In one embodiment, the antenna array includes two independently switchable and steerable antenna groups, each allowing switching between a fixed wide beam and associated coverage / area with a steerable narrow beam. Each antenna group is configured to operate in a MIMO (Multiple-Input Multiple-Output) arrangement according to various communication standards. In various embodiments, the Butler matrix steers the main beam to form various coverage patterns based on the physical layout of the antennas and the wireless communication requirements of the location.

[0021] Figure 1A and Figure 1B The coverage areas 120a, 120b of the antenna arrays 110a, 110b included therein, according to embodiments of the present disclosure, are shown. Figure 1A Isometric views of the coverage areas 120a and 120b associated with AP 150 and wide-beam arrays 110a and 110b are provided, while Figure 1B A top view of coverage areas 120a, 120b (e.g., in the YX plane) is provided. When switching to use wide beam arrays 110a, 110b, AP 150 can transmit and receive signals with various devices located within the corresponding coverage areas 120a, 120b of those wide beam arrays 110a, 110b. Wide beam arrays 110a, 110b generate corresponding fixed beams 130a, 130b (i.e., non-electronically steerable beams) to generate corresponding coverage areas 120a, 120b centered on a given point 140a, 140b in the environment. As shown, fixed beams 130a, 130b are shown emanating from the corresponding wide beam arrays 110a, 110b at the center of the corresponding coverage areas 120a, 120b.

[0022] Figures 2A-2F The coverage area 220a-f of the antenna arrays 210a, 210b included therein, according to embodiments of the present disclosure, is shown. Figure 2A , Figure 2C and Figure 2E Isometric views of the coverage area 220a-f associated with AP 150 and narrow beam arrays 210a and 210b are provided, while Figure 2B , Figure 2D and Figure 2FA top view of coverage areas 220a-f (e.g., in the YX plane) is provided. When switching to use narrow beam arrays 210a, 210b, AP 150 can transmit and receive signals with various devices located within the respective coverage areas 220a-f of those narrow beam arrays 210a, 210b. Narrow beam arrays 210a, 210b generate corresponding steerable beams 230a-f (i.e., beams electronically steerable to different transmission angles relative to narrow beam arrays 210a, 210b) to generate corresponding coverage areas 220a-f, 220b centered on a given point 240a-c in the environment. As shown, the steerable beams 230a-f are shown emanating from the respective narrow beam arrays 210a, 210b at the center of the corresponding coverage areas 220a-f.

[0023] Figures 2A-2F Each figure in the diagram illustrates three potential steering arrangements of a second narrow beam array 210b associated with one potential steering arrangement of the first narrow beam array 210a in a given figure. Each of the narrow beam arrays 210a and 210b is independent of each other and can be steered individually; therefore, in an embodiment with X potential steering arrangements, there are X... 2 There are nine potential overall arrangements. For example, the first narrow beam array 210a and the second narrow beam array 210b each have three potential steering states, and together they provide a total of nine different potential steering arrangements.

[0024] Figure 2A and Figure 2B A first narrow beam array 210a is shown, which generates a narrow beam 230a with a first narrow coverage area 220a at a first position, and a second narrow beam array 210b is shown, which generates corresponding fourth narrow beams 230d, fifth narrow beam 230e, and sixth narrow beams 230f with fourth narrow coverage areas 220d, fifth narrow coverage areas 220e, and sixth narrow coverage areas 220f, respectively. The first narrow coverage area 220a and the fourth narrow coverage area 220d form a line-of-sight coverage pattern, wherein there is significant overlap between the coverage areas of the different beam arrays 210a and 210b (e.g., the maximum overlap of the potential patterns). As the second narrow beam array 210b turns the narrow beam from the fourth position 230d to the fifth position 230e and from the fifth position 230e to the sixth position 230f (i.e., further away from the first narrow coverage area 220a than the fourth coverage area 220d), the overlap between coverage areas decreases. Although in Figure 2A and Figure 2BThe first coverage area 220a is shown to have at least some overlap with the fifth coverage area 220e and the sixth coverage area 220f, but in various embodiments, there may be spatial isolation between the first coverage area 220a and one or more of the fifth coverage area 220e and the sixth coverage area 220f, wherein there is no overlap between the respective coverage areas.

[0025] Figure 2C and Figure 2D A first narrow beam array 210a is shown, which generates a narrow beam 230b with a second narrow coverage area 220b at a second position, and can generate corresponding fourth narrow beams 230d, fifth narrow beam 230e, and sixth narrow beams 230f with fourth narrow coverage areas 220d, fifth narrow coverage areas 220e, and sixth narrow coverage areas 220f, respectively. Compared to the first narrow coverage area 220a, the second narrow coverage area 220b provides less overlap and / or greater spatial isolation for the fourth narrow coverage areas 220d, fifth narrow coverage areas 220e, and sixth narrow coverage areas 220f, respectively.

[0026] Figure 2E and Figure 2F The diagram illustrates a narrow beam 230c with a third narrow coverage area 220c at a third position, generated by a first narrow beam array 210a, and corresponding fourth narrow beams 230d, fifth narrow beam 230e, and sixth narrow beams 230f, respectively, generated by a second narrow beam array 210b. The third narrow coverage area 220c and sixth narrow coverage area 220f form an extended linear coverage pattern, with significant spatial isolation between the coverage areas of the different beam arrays 210a and 210b (e.g., the maximum spatial isolation of the potential patterns). Compared to the second narrow coverage area 220b, the third narrow coverage area 220c provides less overlap and / or greater spatial isolation to the fourth narrow coverage area 220d, fifth narrow coverage area 220e, and sixth narrow coverage area 220f, respectively.

[0027] Figure 3A and Figure 3B The diagram illustrates the overlap of wide coverage areas 120a, 120b of wide beam arrays 110a, 110b (not shown) and narrow coverage areas 220a-f of narrow beam arrays 210a, 210b (not shown) according to embodiments of the present disclosure.

[0028] The first wide coverage area 120a and the second wide coverage area 120b are shown to encompass all narrow coverage areas 220a-f. In some embodiments, the first wide coverage area 120a may include associated narrow coverage areas 220a-c generated in a shared antenna segment and some, but not all, narrow coverage areas 220d-f generated in different antenna segments. Similarly, in some embodiments, the second wide coverage area 120b may include associated narrow coverage areas 220d-f generated in a shared antenna segment and some, but not all, narrow coverage areas 220a-c generated in different antenna segments. Thus, for example, due to high user density in the environment (all of which are competing for limited bandwidth or user capacity in a given AP 150), the AP may switch to wide coverage areas 120a, 120b to serve a larger area in the environment and switch to narrow coverage areas 220a-f to serve a smaller (and therefore more selective) area in the environment.

[0029] Despite Figure 3A The cross-section is shown as approximately circular, but it will be understood that coverages 120a, 120b, and 220a-f can have other shapes depending on the number of elements in each array. For example, in Figure 3B In this design, coverage areas 120a and 120b are shown as asymmetrical (e.g., non-circular oval), which allows for smaller differences in the areas served by the wide-beam array and the narrow-beam array. It will also be understood that the various embodiments can cover areas with greater spatial isolation, less spatial isolation, greater overlap, less overlap, etc., between the various coverage areas. Figure 3A and Figure 3B A non-restrictive example of overlapping coverage is provided.

[0030] Figure 4A and Figure 4B The turning position and offset of a narrow beam array 210 according to an embodiment of the present disclosure are shown. Figure 4A A first set of turning positions 410a, 420a, and 430a of a first narrow-beam array 210a and a second set of turning positions 410b, 420b, and 430b of a second narrow-beam array 210b relative to a reference line 440 are shown. The reference line 440 is perpendicular to the mounting direction of the antenna array including the narrow-beam array 210. For example, when the antenna array is mounted horizontally (e.g., to a ceiling, the underside of a passageway, a horizontal support, or a pillar), the reference line 440 is vertically aligned; however, when the antenna array is mounted vertically (e.g., to a wall, the side of a passageway, a vertical support, or a pillar), the reference line is horizontally aligned. Therefore, this set of turning positions is in the azimuth plane relative to the reference line 440.

[0031] The first narrow beam array 210a can redirect the narrow beam to correspond to the second narrow coverage area 220b (according to...). Figure 2C and Figure 2D The first neutral position 410a (also known as the first zero offset position) corresponds to the third narrow coverage area 220c (according to) Figure 2E and Figure 2F The first negative offset 420a and the corresponding first narrow coverage area 220a (according to) Figure 2A and Figure 2B The first positive offset 430a. Similarly, the second narrow beam array 210b can direct the narrow beam to correspond to the fifth narrow coverage area 220e (according to...). Figures 2A-2F The second neutral position 410b (also known as the second zero offset position) corresponds to the fourth narrow coverage area 220d (according to) Figures 2A-2F The second negative offset 420b and the corresponding sixth narrow coverage range 220f (according to) Figures 2A-2F The second positive offset is 430b.

[0032] Each offset (positive and negative) adjusts the angle of the corresponding narrow beam by a uniform amount from the corresponding neutral position. The first positive offset 430a and the second negative offset 420b align the corresponding narrow beams parallel to the reference line 440. The first narrow beam array 210a and the second narrow beam array 210b are positioned in a plane inclined relative to the reference line 440, the angle of inclination being set based on the steerable angle of the corresponding narrow beam. For example, when the steerable angle between the first neutral position 410a and the first positive offset 430a is R degrees, the first narrow beam array 210a is tilted in the opposite direction by R degrees, such that the angle between the first neutral position 410a and the reference line 440 is -R degrees, and the first positive offset 430a is parallel to the reference line 440. Continuing this example, the difference from the first neutral position 410a to the first negative offset 420a is -T degrees, where, in various embodiments, T may be equal to or not equal to R.

[0033] Figure 4BAdjustments are shown from a reference line 440 marked at position 0, a first neutral position 410a marked at position -X, and a second neutral position 410b marked at position +X. Each narrow beam array 210 can be steered from the neutral positions 410a / 410b in positive or negative increments to make the beam parallel to the reference line 440 (e.g., at position 0) or aligned with the reference line 440 at positions ±Y. Steering angles 450a-d between the different positions are shown such that the first steering angle 450a is equal to the fourth steering angle 450d (e.g., the first neutral position 410a and the first negative offset 420a, and the second neutral position 410b and the second positive offset 430b), and the second steering angle 450b is equal to the third steering angle 450c (e.g., the first neutral position 410a and the first positive offset 430a, and the second neutral position 410b and the second negative offset 420b). In some embodiments, all steering angles 450a-d are equal to each other, while in other embodiments, the two sets of steering angles 450a / 450d and 450b / 450c are different from each other. As will be understood, depending on the terrain or the presence of walls or other obstacles in the environment (and whether the antenna array is mounted vertically, horizontally, or at some intermediate angle), steering the beam at equal angles in opposite directions may not result in a uniform shift of the coverage area. Furthermore, portions of the coverage area located at different distances from the antenna array may experience different signal strengths.

[0034] Figure 5 The component layout of an antenna segment 500 according to an embodiment of the present disclosure is shown. Each antenna segment 500 is configured to operate a narrow-beam antenna array 510 and a wide-beam antenna array 550 (for a given time). The narrow-beam antenna array 510 provides an N×N array of antenna elements, while the wide-beam antenna array 550 provides a 1×M array of antenna elements. The number of elements in the array (e.g., the individual signaling elements that make up the antenna array) determines the beamwidth at the azimuth and elevation angles. The layout of the narrow-beam antenna array 510 provides an (N-2)×(N-2) subset of internal antenna elements 512, which are surrounded by a subset of external antenna elements (i.e., those antenna elements in the narrow-beam antenna array 510 that are not adjacent to at least four antennas).

[0035] Narrow-beam antenna array 510 and wide-beam antenna array 550 are dual-polarization antenna arrays. Through dual polarization, two different radio paths can use the same array simultaneously. One path is connected to a vertical polarization feed, while the other is connected to a horizontal polarization feed, effectively providing two antenna arrays with a single set of elements.

[0036] Signals are routed to or from either narrow-beam antenna array 510 or wide-beam antenna array 550 via a switching path. The switching path includes several switches 530a-b and 540a-b that route signals to / from the active antenna array. Base station switches 540a-b determine whether a signal is routed to or from the narrow-beam array 510 or wide-beam antenna array 550, while intermediate switches 530a-b route signals to / from the phase shifters 520a-b connected to / from the narrow-beam antenna array 510. Although one arrangement of switch components has been described, it will be understood that various other arrangements of switch components (including cascaded 2:1 switches) can be used to link antenna arrays to various signaling sources.

[0037] The low sidelobes created by significantly tapering the narrow beam prevent APs at the same frequency from detecting each other's transmissions, even when installed very close to each other (e.g., within 50 feet). In some embodiments, the sidelobes have an amplitude of -30 dB relative to the main lobe of the narrow beam. In various embodiments, unequal power dividers and attenuators are used to provide lower power signals to the external antenna elements of the narrow beam antenna array 510 than to the internal antenna elements, thereby reducing the power of the sidelobes relative to the main lobe. Due to the control of the sidelobe amplitude, the bandpass filters 560a-b, which are typically used to increase isolation between radios located in the same location within the AP, can be omitted from antenna segment 500 (and any antenna array including antenna segment 500) due to the control of the sidelobe amplitude, although in some embodiments the bandpass filters may be retained to increase isolation between radios located in the same location.

[0038] A pair of phase shifters 520a-b are connected to each feed of the dual-polarization narrow-beam antenna array 510, thereby allowing steering of each polarization of the beam. These positions can include a neutral position with no steering applied, a positive offset from the neutral position in a first direction, and a negative offset from the neutral position in a second direction opposite to the first direction. In each respect, the phase shifters 520a-b are Butler matrices, but other switched phase feed networks can also be used as phase shifters 520a-b to steering the beam in discrete increments while maintaining minimum sidelobes, wherein the first phase shifter 520a steering the vertically polarized first beam by phase shifting a first signal on a column of the narrow-beam antenna array 510, and wherein the second phase shifter 520b steering the horizontally polarized first beam by phase shifting a second signal on a column of the narrow-beam antenna array 510.

[0039] In various embodiments, phase shifters 520a-b steer the narrow beam by generating relative phase differences in the columns of the narrow beam array 510. For example, when steer positively, if the first column 511a has a phase of A, then the second column 511b will have a phase of A+B, where B is a fixed phase difference determined to produce the desired degree of steer; the third column 511c will have a phase of A+(2*B); and the fourth column 511d will have a phase of A+(3*B). For steer negatively, if the first column 511a has a phase of A, then the second column 511b will have a phase of AB, where B is a fixed phase difference determined to produce the desired degree of steer; the third column 511c will have a phase of A-(2*B); and the fourth column 511d will have a phase of A-(3*B). To maintain a neutral or zero-offset position, the phases on columns 511a-d are all equal.

[0040] The wide-beam antenna array 550 generates a fixed-position beam (e.g., Figure 1A and Figure 1B The beams 130a and 130b discussed in the text, while the narrow beam antenna array 510 generates an electronically steerable beam (e.g., Figures 2A-2F (The beams 230a-f discussed herein). The narrow-beam antenna array 510 generates a beam with a first beamwidth smaller than the beamwidth of the beam generated by the wide-beam antenna array 550. In various embodiments, the beamwidth of the beam generated by the wide-beam antenna array 550 includes or encompasses the entire coverage area of ​​the beam generated by the narrow-beam antenna array 510, which is redirected to any of its potential locations.

[0041] Figure 6 The component layout of an antenna array 600 according to an embodiment of the present disclosure is shown. The antenna array 600 includes components as described above. Figure 5 The four instances of antenna segments 500a-d and interface 610, which act as a signal source for signals transmitted via antenna segments 500a-d, can be used as a steerable and switchable antenna array for various APs in locations where available bandwidth is very scarce. In various embodiments, two or more radios are connected to antenna segments 500a-d (and / or alternative antennas) via interface 610.

[0042] In various embodiments, additional alternative antennas may also be connected (via one or more switches) to various ports of interface 610 to allow the use of different frequencies, communication standards, or beam patterns in antenna array 600. For example, antenna segments 500a-d may operate in a first frequency bandwidth (e.g., 5 GHz) of all radios transmitting signals from ports (e.g., ports ABCD and EFGH) via interface 610, but additional antennas (not shown) connected to a subset of ports (e.g., port EGHG) may operate in a second frequency bandwidth (e.g., 2.4 GHz).

[0043] Using four instances of antenna array 600, the APs are configured to operate in dual 4×4 MIMO mode without mutual interference between radios. Therefore, antenna array 600 allows for high channel reuse in high-density applications, where several APs are deployed together with corresponding instances of antenna array 600, thanks to beamforming and attenuation provided by the individual antenna segments 500a-d (e.g., precise antenna patterns with low sidelobe levels). Switchable beam orientation allows for flexible cell alignment in the same or adjacent coverage areas of different APs, enabling several APs to be closely grouped together (e.g., within 50 feet of each other).

[0044] Figure 7 This is a flowchart of a method 700 for managing an electronically steerable antenna array according to embodiments of the present disclosure. Method 700 can be performed independently by each antenna group in the antenna array, such that each beam independently switches to / from a narrow or wide configuration, and independently steers to various positions when in a narrow configuration. As will be understood, elements of method 700 are essentially performed using the antenna array disclosed herein, and one or more blocks can be performed substantially in parallel or simultaneously with other blocks of method 700, and method 700 can be periodically looped or repeated as the antenna array is controlled to update the way coverage is generated.

[0045] In block 710, the antenna array switches between wide coverage mode and narrow coverage mode. The access point (AP) connected to the antenna array can signal which operating mode to switch to based on factors such as the coverage requirements of various sites communicating with the AP, the signal propagation characteristics of the environment, and the number of sites attempting to communicate with the AP. When the antenna array switches to narrow coverage mode, method 700 proceeds to block 720. When the antenna array switches to wide coverage mode, method 700 proceeds to block 760.

[0046] In block 720, by activating the narrow beam array, the antenna array forms a narrow beam with a narrow coverage area. The narrow beam array can transmit and receive signals through various polarizations to reuse available hardware and available spectrum. When forming the narrow beam, the antenna array diminishes the amplitude of the narrow beam by providing lower power to the external elements of the narrow beam array than to the internal elements (according to block 730) and determines where to steer the narrow beam. In various embodiments, the difference in power supplied to the internal and external elements of the narrow beam array produces a beam with sidelobes whose power level is -30 dB relative to the power level of the main beam. This allows several APs using the antenna array to be placed close to each other (e.g., within 50 feet of each other) and use the same channel without interfering with each other or causing crosstalk between APs.

[0047] In block 740, the antenna array steers the narrow beam to a desired offset. In various embodiments, the antenna array can steer the narrow beam to one of three positions by: leaving the narrow beam in a neutral position; applying a positive phase shift to the signal on a column of the narrow beam array to steer the narrow beam to a positive offset; or applying a negative phase shift to the signal on a column of the narrow beam array to steer the narrow beam to a negative offset.

[0048] When both narrow-beam arrays are in narrow mode, the antenna arrays can provide a variety of different coverage patterns, such as Figures 2A-2F As shown. For example, when the first coverage area is turned to a first positive offset and the second coverage area is turned to a second negative offset, the antenna array produces a line-of-sight pattern where, given the turning options, each coverage area overlaps as much as possible. Conversely, when the first coverage area is turned to a first negative offset and the second coverage area is turned to a second positive offset, given the turning options, the antenna array produces an extended linear pattern with maximum spatial isolation between the two coverage areas. The antenna array can produce additional coverage patterns with intermediate levels of overlap / spatial isolation based on the wireless communication needs of the sites served by the associated APs.

[0049] In box 750, by activating the wide beam array, the antenna array forms a wide beam with a wide coverage area. The wide beam array is neither diminishing nor backward-facing, and provides a wide coverage area that encompasses the range of the narrow beam at each backward-facing position.

[0050] Once a beam (narrow or wide) is formed, method 700 proceeds to block 760, where the antenna array transmits and receives signals according to the beam formed within the corresponding coverage area. Then, when the beam is re-formed (e.g., switching from a narrow beam to a wide beam, switching from a wide beam to a narrow beam, turning to a different offset, etc.), method 700 can end or restart at block 710.

[0051] Figure 8 Hardware for a computing device 800, which can be used in the AP 150 described herein, is shown. The computing device 800 includes a processor 810, memory 820, and a communication interface 830. The processor 810 can be any processing element capable of performing the functions described herein. The processor 810 represents a single processor, multiple processors, a processor with multiple cores, or combinations thereof. The communication interface 830 facilitates communication between the computing device 800 and other devices such as interface 830. The memory 820 can be volatile or non-volatile memory and can include RAM, flash memory, cache, disk drives, and other computer-readable storage devices. Although shown as a single entity, the memory 820 can be divided into different memory storage elements, such as RAM and one or more hard disk drives.

[0052] As shown, memory 820 includes various instructions executable by processor 810 to provide operating system 821 to manage various functions of computing device 800 and to provide one or more applications 822 to provide various functions to users of computing device 800, including one or more functions and features described in this disclosure.

[0053] Various embodiments have been referenced in this disclosure. However, the scope of this disclosure is not limited to the embodiments specifically described. Rather, any combination of the described features and elements is contemplated for implementation and practice, regardless of whether it is associated with a different embodiment. Furthermore, when elements of an embodiment are described in the form of "at least one of A and B," it will be understood that embodiments including element A alone, including element B alone, and including both elements A and B are all considered. Moreover, while some embodiments disclosed herein may achieve advantages over other possible solutions or prior art, whether a given embodiment achieves a particular advantage does not limit the scope of this disclosure. Therefore, the aspects, features, embodiments, and advantages disclosed herein are merely illustrative and should not be considered elements of the claims or limitations thereof unless expressly stated in one or more claims. Similarly, unless expressly stated in one or more claims, references to "the invention" should not be construed as a generalization of any inventive subject matter disclosed herein and should not be considered elements of or limitations of the appended claims.

[0054] As those skilled in the art will understand, the embodiments disclosed herein can be embodied as systems, methods, or computer program products. Therefore, embodiments can take the form of entirely hardware embodiments, entirely software embodiments (including firmware, resident software, microcode, etc.), or embodiments combining software and hardware aspects, all of which can be collectively referred to herein as “circuit,” “module,” or “system.” Furthermore, embodiments can take the form of computer program products embodied in one or more computer-readable media having computer-readable program code embodied thereon.

[0055] Any suitable medium may be used to transmit program code embodied on a computer-readable medium, including but not limited to wireless, wired, fiber optic cable, RF, or any suitable combination thereof.

[0056] Computer program code used to perform the operations of embodiments of this disclosure may be written in any combination of one or more programming languages, including object-oriented programming languages ​​(e.g., Java, Smalltalk, C++, etc.) and traditional procedural programming languages ​​(e.g., the "C" programming language or similar programming languages). The program code may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0057] This document describes aspects of the present disclosure with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments presented herein. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create tools for implementing the functions / actions specified in the blocks of the flowchart illustrations and / or block diagrams.

[0058] These computer program instructions may also be stored in a computer-readable medium that can direct a computer, other programmable data processing apparatus or other device to operate in a particular manner, such that the instructions stored in the computer-readable medium produce an article of writing which includes instructions that perform functions / actions specified in boxes of flowcharts and / or block diagrams.

[0059] Computer program instructions may also be loaded onto a computer, other programmable data processing apparatus or other equipment to cause a series of operational steps to be performed on the computer, other programmable apparatus or other equipment to produce a computer-implemented process, such that the instructions, which execute on the computer, other programmable data processing apparatus or other equipment, provide a process for implementing the functions / actions specified in the frames of a flowchart and / or block diagram.

[0060] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments. In this regard, each block in the flowchart or block diagram may represent a module, segment, or code portion, which includes one or more executable instructions for implementing one or more specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the blocks may not appear in the order indicated in the figures. For example, depending on the functions involved, two blocks shown consecutively may actually be executed substantially simultaneously, or sometimes these blocks may be executed in reverse order. It will also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, may be implemented by a dedicated hardware-based system that performs the specified function or action or a combination of dedicated hardware and computer instructions.

[0061] In view of the foregoing, the scope of this disclosure is defined by the appended claims.

Claims

1. An apparatus for wireless communication, comprising: a plurality of antenna segments, each antenna segment comprising: a narrow-beam antenna array configured to produce a first beam having a first beamwidth; a wide-beam antenna array configured to produce a second beam having a second beamwidth that is greater than the first beamwidth of the first beam; a switching path configured to selectively activate one of the narrow-beam antenna array or the wide-beam antenna array at a given time; a first phase shifter and a second phase shifter connected between the switching path and the narrow-beam antenna array, the first and second phase shifters configured to steer the first beam from a first position to a second position in an azimuth plane; wherein, when a given first beam of a given antenna segment of the plurality of antenna segments is steered to the first position and a different first beam of a different antenna segment of the plurality of antenna segments is steered to the first position, respective coverage areas of the given first beam and the different first beam overlap; and wherein, when the given first beam is steered to the second position and the different first beam is steered to the second position, respective coverage areas of the given first beam and the different first beam are spatially isolated from each other.

2. The apparatus of claim 1, wherein, applying an amplitude taper to the narrow-beam antenna array such that outer antenna elements of the narrow-beam antenna array receive less power than inner antenna elements of the narrow-beam antenna array, thereby reducing power of a sidelobe relative to a main lobe of the first beam.

3. The apparatus of claim 1 or 2, further comprising a bandpass filter included between one of radio paths of the narrow-beam antenna array and the wide-beam antenna array and the switching path.

4. The apparatus of claim 1 or 2, wherein, radio paths of the narrow-beam antenna array and the wide-beam antenna array are directly connected to the switching path.

5. The apparatus of claim 1 or 2, wherein, the given first beam is further steerable to a third position that is intermediate the first position and the second position, wherein the third position is a neutral position in which the first phase shifter and the second phase shifter do not apply steering.

6. The apparatus of claim 5, wherein: when the given first beam is steered to the first position and the different first beam is steered to the second position, respective coverage areas of the given first beam and the different first beam are spatially isolated from each other to a lesser extent than when both the given first beam and the different first beam are steered to the second position; and when the given first beam is steered to the first position and the different first beam is steered to the third position, respective coverage areas of the given first beam and the different first beam overlap each other to a lesser extent than when both the given first beam and the different first beam are steered to the first position.

7. The apparatus of claim 5, wherein, When the given first beam and the different first beam are steered to the third location, the respective coverage of the given first beam and the different first beam are spatially isolated from each other that is less than when both the given first beam and the different first beam are steered to the second location.

8. The apparatus of claim 5, wherein, When the given first beam and the different first beam are steered to the third location, the respective coverage of the given first beam and the different first beam spatially partially overlap with each other that is less than when both the given first beam and the different first beam are steered to the first location.

9. The apparatus of claim 1 or 2, wherein, The coverage of the wide beam antenna array includes the respective coverage of the first beam at the first location and at the second location.

10. The apparatus of claim 1 or 2, wherein, The narrow beam antenna array and the wide beam antenna array are dual polarized.

11. The apparatus of claim 10, wherein, The first phase shifter steers the first beam for a vertical polarized signal by phase shifting a first signal on a column of the narrow beam antenna array, and wherein the second phase shifter steers the first beam for a horizontal polarized signal by phase shifting a second signal on a column of the narrow beam antenna array.

12. A system for wireless communication, comprising: a steerable and switchable antenna array configured to produce a first beam having a first coverage and a second beam having a second coverage; a processor; and a memory storing instructions that, when executed by the processor, cause the steerable and switchable antenna array to: select one of a first beam width and a second beam width for both the first beam and the second beam; in response to selecting the first beam width, perform the following operations: switch a signal input to a narrow beam antenna array included in the steerable and switchable antenna array; steer the first beam to one of a first positive offset, a first negative offset, and a first neutral location; steer the second beam to one of a second positive offset, a second negative offset, and a second neutral location; and transmit signals received from the signal input via the first beam and the second beam; and in response to selecting the second beam width, perform the following operations: switch a signal input to a wide beam antenna array included in the steerable and switchable antenna array; and transmit signals received from the signal input via the first beam and the second beam. The instructions, when executed by the processor, further cause the steerable and switchable antenna array to: shape the first beam and the second beam to have a side lobe having a magnitude of -30 dB relative to a main lobe of the first beam and the second beam.

13. The system of claim 12, wherein, channels selected for the first beam are reused by other access points within 50 feet of the steerable and switchable antenna array. The first beam and the second beam are steered via phase shifting signals on columns of antenna columns of the narrow beam antenna array.

14. The system of claim 13, wherein, The system operates in a 4x4 MIMO mode.

15. The system of any one of claims 12 to 14, wherein, The first beam and the second beam are steered via phase shifting signals on columns of antenna columns of the narrow beam antenna array.

16. The system of any one of claims 12 to 14, wherein, ​ 17. The system of any one of claims 12 to 14, wherein, The first beam and the second beam are steered via a Butler matrix.

18. A method for wireless communication, comprising: forming a first beam having a first coverage range by a first antenna segment, wherein forming the first beam comprises: tapering a first amplitude of the first beam by providing lower power to outer elements of a first antenna array than to inner elements of the first antenna array; and steering the first beam from a first neutral position to one of a first positive offset and a first negative offset by phase shifting signals to transmit according to the first beam on columns of the first antenna array; forming a second beam having a second coverage range by a second antenna segment, wherein forming the second beam comprises: tapering a second amplitude of the second beam by providing lower power to outer elements of a second antenna array than to inner elements of the second antenna array; and steering the second beam from a second neutral position to one of a second positive offset and a second negative offset by phase shifting signals to transmit according to the second beam on columns of the second antenna array; wherein the first coverage range and the second coverage range form a boresight pattern when the first beam is steered to the first positive offset and the second beam is steered to the second negative offset; and wherein the first coverage range and the second coverage range form an extended linear pattern with spatial isolation between the first coverage range and the second coverage range when the first beam is steered to the first negative offset and the second beam is steered to the second positive offset.

19. The method of claim 18, wherein, Beamforming and amplitude tapering result in beams with -30 dB sidelobes relative to the main beam, where the channel selected for the first beam is reused by other access points within 50 feet of the first antenna segment.

20. The method of claim 18 or 19, further comprising: in the first antenna segment, switching from the first antenna array to a second antenna array to produce a third beam having a wider beamwidth than the first beam, wherein a coverage range of the third beam contains a coverage range of the first beam in each of the first positive offset, the first neutral position, and the first negative offset; and in the second antenna segment, switching from the second antenna array to a fourth antenna array to produce a fourth beam having a wider beamwidth than the second beam, wherein a coverage range of the fourth beam contains a coverage range of the second beam in each of the second positive offset, the second neutral position, and the second negative offset.

Images