PATENT DOCUMENT

Publication Number: US-11552405-B1
Application Number: US-201916576148-A
Country: US
Kind Code: B1

Title: Lens structure

Abstract:
A communication terminal may include an array of antenna modules. Each module may include an array of radiators on a substrate and a radio-frequency lens overlapping the array. The lens may include a tapered base on the substrate and a curved portion on the tapered base. The tapered base and curved portions may be rotationally symmetric about a central axis of the lens. The curved portion may be hemispherical. The tapered base portion may be conical and may have a first radius at the hemispherical portion and a second radius that is less than the first radius at the substrate. At least one radiator in the array may be located beyond the first radius and within the second radius from the central axis. The lens may be formed from lattice having interleaved layers of dielectric segments separated by gaps to reduce the overall weight of the module.

Claims:
What is claimed is: 
     
       1. An antenna module comprising:
 an array of antenna radiators; and 
 a lens having a first portion and a second portion on the first portion, wherein the first portion is between the second portion and the array, the second portion at least partially overlaps the antenna radiators in the array, the antenna radiators in the array are configured to convey radio-frequency signals through the lens, the lens has a central axis, the first portion has a radius at the array of antenna radiators, and at least a portion of at least one antenna radiator in the array of antenna radiators is located beyond the radius from the central axis. 
 
     
     
       2. The antenna module defined in  claim 1 , further comprising:
 a transceiver chain configured to generate the radio-frequency signals at a selected phase; and 
 switching circuitry configured to selectively activate a set of antenna radiators in the array, wherein the lens is configured to transmit the radio-frequency signals from the antenna radiators of the activated set in a respective direction. 
 
     
     
       3. The antenna module defined in  claim 1 , further comprising:
 an additional array of antenna radiators, wherein the array of antenna radiators is configured to transmit first radio-frequency signals in a first frequency band through the lens and the additional array of antenna radiators is configured to transmit second radio-frequency signals in a second frequency band that is different from the first frequency band through the lens. 
 
     
     
       4. The antenna module defined in  claim 3 , wherein the first frequency band comprises a frequency band selected from the group consisting of: a K a  frequency band, a Q frequency band, and a K u  frequency band, and a V frequency band. 
     
     
       5. The antenna module defined in  claim 4 , wherein the lens has a dielectric constant between 2.0 and 4.0. 
     
     
       6. The antenna module defined in  claim 5 , wherein the lens comprises plastic. 
     
     
       7. The antenna module defined in  claim 1 , wherein the first portion and the second portion are rotationally symmetric about the central axis. 
     
     
       8. The antenna module defined in  claim 7 , wherein the second portion has a hemispherical shape. 
     
     
       9. The antenna module defined in  claim 7 , wherein the first portion has a conical shape. 
     
     
       10. The antenna module defined in  claim 1 , wherein the first portion has a second radius at the second portion that is greater than the first radius, the lens having a total height greater than the second radius. 
     
     
       11. The antenna module defined in  claim 10 , wherein the lens comprises a protruding lip at the array of antenna radiators. 
     
     
       12. An antenna module comprising:
 an array of antenna radiators; and 
 a lens having a tapered base portion and a curved portion on the tapered base portion, wherein the antenna radiators in the array are configured to convey radio-frequency signals through the lens, the tapered base portion has a first radius at the array of antenna radiators and a second radius at the curved portion that is greater than the first radius, and an antenna radiator from the array of antenna radiators is positioned beyond the first radius. 
 
     
     
       13. The antenna module defined in  claim 1 , wherein the radio-frequency signals are conveyed through the lens in a frequency band and the lens comprises dielectric gaps and dielectric segments each having a corresponding width that is less than one-fifth of a wavelength corresponding to a frequency within the frequency band. 
     
     
       14. An antenna module comprising:
 at least one antenna; and 
 a lens that at least partially overlaps the at least one antenna, that has a central axis, and that is configured to redirect radio-frequency signals across a field of view, the lens comprising:
 a first portion; and 
 a second portion on the first portion, wherein the first portion has a first end at the second portion and an opposing second end, the first end has a first radius, the second end has a second radius that is less than the first radius, and at least a portion of the at least one antenna lies beyond the second radius from the central axis. 
 
 
     
     
       15. The antenna module defined in  claim 14 , wherein the lens has a total height that is greater than the first radius and wherein the first radius is between one and four times a wavelength of the radio-frequency signals. 
     
     
       16. The antenna module defined in  claim 14 , wherein the first portion and the second portion comprise stacked layers of dielectric segments separated by horizontal gaps, wherein the horizontal gaps and the dielectric segments configure the lens to exhibit a bulk dielectric constant between 2.0 and 4.0. 
     
     
       17. The antenna module of  claim 14 , wherein the first portion has a tapered shape and the second portion has a curved shape. 
     
     
       18. The antenna module of  claim 1 , wherein the first portion has a tapered shape, the first portion has an additional radius at the second portion, and the additional radius is greater than the radius. 
     
     
       19. The antenna module of  claim 18 , wherein the second portion has a curved shape. 
     
     
       20. The antenna module of  claim 12 , wherein the curved portion of the lens at least partially overlaps each of the antenna radiators in the array, the lens has a central axis, and a farthest antenna radiator from the central axis in the array of antenna radiators is positioned beyond the first radius and within the second radius from the central axis.

Description:
This application claims the benefit of provisional patent application No. 62/734,684, filed Sep. 21, 2018, which is hereby incorporated by reference herein in its entirety. 
    
    
     FIELD 
     This relates generally to lens structures, including lens structures for wireless communications systems. 
     BACKGROUND 
     Communication terminals such as communication terminals integrated into electronic devices, satellites, or other systems often include wireless components. The wireless components include one or more antennas that convey wireless data with other communication terminals in a wireless communications system. 
     In long-range wireless communications systems such as satellite communications systems, communication terminals typically convey radio-frequency signals over long distances such as tens, hundreds, or thousands of miles. These distances subject the radio-frequency signals to substantial signal attenuation during propagation. In addition, the communication terminals often need to maintain several concurrent wireless links with other communication terminals in the satellite communications system. 
     If care is not taken, wireless components that support this type of long-range communication can consume excessive resources in the communication terminal such as power, space, and weight. It can also be challenging to maintain satisfactory wireless link quality between the communication terminals, particularly over long distances such as those associated with satellite communications systems. 
     Lens structures can be used to help focus radio-frequency signals in a particular direction. However, conventional lens structures exhibit limited gain at relatively high angles off of boresight. 
     SUMMARY 
     A communication terminal in a communications system such as a satellite communications system may include control circuitry and an array of antenna modules. Each antenna module may include an array of antenna radiators on a substrate and a radio-frequency lens overlapping the array of radiators. Each antenna module may include a transceiver chain that includes a transceiver, a phase shifter, and an amplifier shared by each of the radiators in the module. Each antenna module may include switching circuitry between the radiators and the transceiver chain. 
     The control circuitry may control the switching circuitry to activate a set of one or more radiators in a given module. The control circuitry may control the transceiver chain in the module to convey radio-frequency signals at a selected phase using each of the active radiators (e.g., by applying a selected phase shift with the phase shifter in the transceiver chain). Each of the active radiators may transmit and receive the radio-frequency signals over signal beams oriented in different directions by the radio-frequency lens over the module. 
     The radio-frequency lens may include a tapered base portion on the substrate and a curved portion on the tapered base portion. The curved portion may overlap each of the radiators in the array. The tapered base portion and the curved portion may both be rotationally symmetric about a central axis of the lens. The curved portion may be hemispherical. The tapered base portion may be conical and may have a first end at the hemispherical portion and an opposing second end at the substrate. The first end may have a first radius and the second end may have a second radius that is less than the first radius. At least one radiator in the underlying array may be located farther than the first radius and within the second radius from the central axis of the lens. If desired, the lens may be formed from lattice structure having interleaved layers of dielectric segments separated by gaps to reduce the overall weight of the module. 
     The lens may allow the module to support communications links over greater elevation angles relative to boresight than in scenarios where flat panel lenses are used. The lens may redirect multiple concurrent signal beams at one or more frequencies and with any desired polarizations and phases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic diagram of an illustrative communications system (network) that includes multiple communication terminals in accordance with some embodiments. 
         FIG.  2    is a schematic diagram of an illustrative communication terminal in accordance with some embodiments. 
         FIG.  3    is a perspective view of an illustrative patch radiator having multiple feeds in accordance with some embodiments. 
         FIG.  4    is a diagram of a phased antenna array having separate transceiver chains for each radiator in the array in accordance with some embodiments. 
         FIG.  5    is a diagram of illustrative antenna modules having corresponding lenses and radiators that may be selectively activated to direct radio-frequency signals in different directions in accordance with some embodiments. 
         FIG.  6    is a cross-sectional side view of an illustrative antenna module having a lens and an array of radiators that may be selectively activated in accordance with some embodiments. 
         FIG.  7    is a top-down view of an illustrative array of antenna modules each having corresponding lenses and rectangular arrays of radiators in accordance with some embodiments. 
         FIG.  8    is a top-down view of an illustrative array of antenna modules each having corresponding lenses and circular arrays of radiators in accordance with some embodiments. 
         FIG.  9    is a top-down view of an illustrative array of antenna modules that are rotated with respect to each other in accordance with some embodiments. 
         FIG.  10    is a diagram showing how an illustrative array of antenna modules may be controlled to form a phased array of antenna modules in accordance with some embodiments. 
         FIG.  11    is a flow chart of illustrative steps involved in operating a phased array of antenna modules of the type shown in  FIG.  10    in accordance with some embodiments. 
         FIG.  12    is a side-view of an illustrative array of antenna modules that has been arranged in a curved configuration to increase system scan range in accordance with some embodiments. 
         FIG.  13    is a diagram of an illustrative antenna module having radiators coupled to different transceiver chains for conveying radio-frequency signals at different frequencies in accordance with some embodiments. 
         FIG.  14    is a diagram of an illustrative antenna module having a first set of radiators that convey radio-frequency signals at a first frequency and a second set of radiators that convey radio-frequency signals at a second frequency in accordance with some embodiments. 
         FIG.  15    is a perspective view of an illustrative antenna module having first and second sets of radiators for covering respective first and second frequencies in accordance with some embodiments. 
         FIG.  16    is a perspective view of an illustrative radio-frequency lens having hemispherical and conical portions in accordance with some embodiments. 
         FIG.  17    is a perspective view of an array of antenna modules that are each provided with a respective radio-frequency lens in accordance with some embodiments. 
         FIG.  18    is a side view of an illustrative radio-frequency lens having hemispherical and conical portions and high off-boresight gain in accordance with some embodiments. 
         FIG.  19    is a plot of an exemplary antenna radiation pattern through an illustrative radio-frequency lens of the type shown in  FIGS.  16 - 18    in accordance with some embodiments. 
         FIG.  20    is a side view of an illustrative radio-frequency lens formed from a weight-reducing lattice of dielectric material in accordance with some embodiments. 
         FIG.  21    is a perspective view of an illustrative radio-frequency lens formed from a lattice of dielectric material in accordance with some embodiments. 
         FIG.  22    is a perspective view of two layers of dielectric segments that may be used in forming a radio-frequency lens of the type shown in  FIGS.  20  and  21    in accordance with some embodiments. 
         FIG.  23    is a perspective view of illustrative concentric ring and radial spoke layers that may be used in forming a radio-frequency lens of the type shown in  FIGS.  20  and  21    in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     A communications system such as a satellite communications network may include a communication terminal. The communication terminal may include an array of antenna modules. Each antenna module may include a transceiver chain and an array of antenna radiators (sometimes referred to herein as radiators, elements, resonant elements, or resonant antenna elements). The radiators in each module may share the same transceiver chain. Each transceiver chain may include a corresponding transceiver, phase shifter, and amplifier. Switching circuitry may be coupled between each radiator in a given antenna module and the corresponding transceiver chain. 
     Each antenna module may include a lens overlapping some or all of the radiators in that module. Control circuitry may selectively activate different radiators in a given module to generate beams of radio-frequency signals in different pointing directions through the lens. Each lens and each antenna module may support multiple concurrent beams of signals and thus multiple concurrent wireless links with different external communication terminals. 
     The lenses may each include a hemispherical portion on a conical base. The hemispherical portion may serve to increase the effective aperture of the radiators located relatively far from the central axis of the lens. The conical portion may limit side lobe gain for each of the radiators to ensure that the radiators meet industry and regulatory standards on side lobe generation. The lens may have a first radius at its base that overlaps some of the radiators in the module and a second radius where the conical portion meets the hemispherical portion that overlaps each of the radiators in the module. In some scenarios where extreme scan angles greater than 60-70 degrees off boresight are needed, the radiators may be positioned beyond the second lens radius. 
     Weight may be reduced across the array of antenna modules by forming the lenses using a lattice of dielectric segments. The lenses may include alternating layers of elongated dielectric segments extending in different directions. The dielectric segments may be separated by gaps that configure the lens to exhibit a desired bulk dielectric constant. The gaps may be less than one-tenth of the wavelength of operation or less than one-fifth of the wavelength of operation of the antenna module, as examples. The lens may support communications links over a larger field of view (e.g., with external communication terminals at higher angles off of the boresight axis of the module) than in scenarios where flat panel lenses are used. 
     If desired, the control circuitry may adjust the phase shifts provided by the phase shifter in each antenna module to perform beam steering operations across the array of antenna modules. For example, the control circuitry may activate a first radiator in a first module, may activate a second radiator in a second module, and may phase the first and second modules so that the first and second radiators produce a combined signal beam in a particular pointing direction. 
     Each antenna module may include additional arrays of radiators and additional transceiver chains for covering other frequencies if desired. Operating the antenna modules using multiple frequency bands may allow the array of antenna modules to support a greater data throughput per antenna volume relative to flat panel phased antenna arrays. Data throughput may be further increased using multiple different polarizations. In this way, the communication terminal may exhibit enhanced data throughputs, may maintain multiple concurrent wireless links with satisfactory link quality over a wide field of view, and may reduce space consumption, power consumption, and manufacturing cost relative to communications terminals having flat panel phased antenna arrays. 
       FIG.  1    is a diagram of an illustrative communications system  12 . Communications system  12  (sometimes referred to herein as network  12  or communications network  12 ) may include two or more communication terminals  10  that communicate over wireless links. Each communication terminal  10  may include wireless components such as wireless communications circuitry that transmits and/or receives radio-frequency signals using one or more corresponding antennas. Arrangements in which communications system  12  is a satellite communications system that includes communication terminals implemented on one or more satellites (satellite terminals) is sometimes described herein as an example. Communications system  12  may therefore sometimes be referred to herein as satellite system  12 , satellite communications system  12 , or satellite network  12 . 
     In the example of  FIG.  1   , communications system  12  includes a first communication terminal  10 A, a second wireless communication terminal  10 B, a third wireless communication terminal  10 C, and a fourth wireless communication terminal  10 D. Communication terminals  10 A- 10 D may be integrated within electronic devices (e.g., cellular telephones, tablet computers, desktop computers, laptop computers, wearable electronic devices, media players, televisions, set-top boxes, etc.), buildings, kiosks, vehicles, satellites, wireless base stations, wireless access points, satellite network ground stations (gateways), or any other desired systems. In one suitable arrangement that is sometimes described herein as an example, communication terminal  10 A is implemented on a satellite (e.g., a medium earth orbit (MEO) satellite, a low earth orbit (LEO) satellite, a geosynchronous (GEO) satellite, etc.), communication terminal  10 B is implemented on a satellite, communication terminal  10 C is implemented on a satellite network ground station, and communication terminal  10 D is implemented on an electronic device, within a building, kiosk, vehicle, or other system (e.g., communication terminal  10 D may be implemented in a portable electronic device or user equipment such as a cellular telephone, tablet computer, or laptop computer, whereas communication terminal  10 B is implemented on a larger, stationary ground station). 
     As shown in  FIG.  1   , communication terminal  10 A may communicate with communication terminal  10 B over wireless link  16  (e.g., a satellite-to-satellite link), may communicate with communication terminal  10 C over wireless link  14  (e.g., a satellite-to-gateway link), and/or may communicate with communication terminal  10 D over wireless link  18  (e.g., a satellite-to-user equipment link). Communication terminal  10 C may communicate with communication terminal  10 D over wireless link  20  (e.g., a gateway-to-user equipment link). Intervening network components such as wireless base stations, access points, servers, or other networks (e.g., local area networks, the internet, etc.) may additionally or alternatively be used to convey signals between communication terminal  10 C and communication terminal  10 D. If desired, communication terminal  10 C may relay data between communication terminal  10 D and communication terminal  10 A over links  14  and  20  (e.g., so that communication terminal  10 A may relay the wireless data to communication terminal  10 B, other user equipment, or other ground stations that are located far away from communication terminal  10 D). Similarly, communication terminal  10 A may relay data between communication terminal  10 D and communication terminal  10 B over links  18  and  16 . Links  16 ,  18 ,  14 , and  20  may be bidirectional or unidirectional (e.g., data may be conveyed both to terminal  10 A from terminal  10 C and from terminal  10 A to terminal  10 C over link  14  or may be conveyed in only a single direction between terminals  10 A and  10 C). 
     This example is merely illustrative. In general, communications system  12  may include any desired number of communication terminals  10 A and  10 B (e.g., communication terminals implemented on satellites), any desired number of communication terminals  10 C (e.g., communication terminals implemented on ground stations), any desired number of communication terminals  10 D (e.g., any desired user equipment devices), and/or any desired number of communication terminals implemented on other systems such as wireless access points and/or wireless base stations. In practice, communication terminals in communications system  12  such as communication terminals  10 A,  10 B, and  10 C of  FIG.  1    may need to perform wireless communications with two, three, four, or more than four (e.g., tens, hundreds, thousands, etc.) other communication terminals  10  in communications system  12 . 
       FIG.  2    is a diagram of an illustrative communication terminal  10  that may perform wireless communications in communications system  12 . Communication terminal  10  of  FIG.  2    may be, for example, used to form communication terminals  10 A or  10 B (e.g., may be implemented on a satellite in system  12 ), to form communication terminal  10 C (e.g., may be implemented on a ground station in system  12 ), to form communication terminal  10 D (e.g., may be implemented on user equipment in system  12 ), or to form any other desired communication terminal for system  12 . 
     As shown in  FIG.  2   , communication terminal  10  may include control circuitry  22 . Control circuitry  22  may include storage such as nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory), volatile memory (e.g., dynamic or static random-access-memory), hard disk drive storage, etc. Control circuitry  22  may also include processing circuitry that controls the operation of communication terminal  10 . Processing circuitry in control circuitry  22  may include one or more microprocessors, digital signal processors, microcontrollers, application specific integrated circuits, field programmable gate arrays, baseband processor integrated circuits, etc. 
     Control circuitry  22  may be used to run software on communication terminal  10 , such as software applications, operating system functions, etc. Control circuitry  22  may be used in implementing wireless communications protocols. Wireless communications protocols that may be implemented using control circuitry  22  include satellite communications protocols, internet protocols, wireless local area network protocols (e.g., IEEE 802.11 protocols—sometimes referred to as WiFi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol or other wireless personal area network protocols, IEEE 802.11ad protocols, cellular telephone protocols, MIMO protocols, antenna diversity protocols, etc. 
     Communication terminal  10  may include input-output circuitry  24 . Input-output circuitry  24  may include wireless circuitry  26  (sometimes referred to herein as wireless communications circuitry  26 ) for communicating wirelessly with external equipment (e.g., other communication terminals  10  in communications system  12  of  FIG.  1   ). Wireless circuitry  26  may include radio-frequency (RF) transceiver circuitry such as one or more radio-frequency transceivers  28 . Radio-frequency transceivers  28  may each be formed from one or more integrated circuits and may include mixer circuitry (e.g., up-converter circuitry for converting from baseband to radio frequencies and down-converter circuitry for converting from radio frequencies to baseband frequencies), analog-to-digital converter circuitry, digital-to-analog converter circuitry, power amplifier circuitry, low-noise amplifier circuitry, passive radio-frequency components (e.g., filter circuitry, impedance matching circuitry, etc.), etc. Wireless circuitry  26  may also include switching circuitry, radio-frequency transmission lines, one or more antenna radiators  30  (e.g., antenna radiators in antenna modules that are phased to produce a phased array antenna), and other circuitry for handling radio-frequency wireless signals. 
     Transceivers  28  may each be satellite communications transceivers. Transceivers  28  may transmit and/or receive radio-frequency signals in any desired satellite communications (frequency) bands using antenna radiators  30 . Communications bands handled by transceivers  28  may include IEEE bands such as the IEEE K a  band (26.5-40 GHz), K u  band (12-18 GHz), K band (18-27 GHz), V band (40-75 GHz), W band (75-110 GHz), X band (8-12 GHz), C band (4-8 GHz), ISO bands such as the ISO Q band (33-50 GHz), and/or any other desired bands (e.g., bands at centimeter wave and millimeter wave frequencies or at frequencies under 10 GHz). If desired, transceivers  28  may include other transceiver circuitry for handling wireless local area network communications, wireless personal area network communications, cellular telephone communications, or other non-satellite and/or terrestrial communications using antenna radiators  30 . Satellite communications data conveyed by transceivers  28  and antenna radiators  30  may include media data (e.g., streaming video, television data, satellite radio data, etc.), voice data (e.g., telephone voice data), Internet data, and/or any other desired data. 
     Antenna radiators  30  (sometimes referred to herein as radiators  30 , elements  30 , resonant elements  30 , or resonant antenna elements  30 ) may include radiators formed using any desired types of antenna structures such as patch antenna structures, stacked patch antenna structures, dipole antenna structures, monopole antenna structures, inverted-F antenna structures, slot antenna structures, planar inverted-F antenna structures, cavity-backed antenna structures, waveguide antenna structures, helical antenna structures, Yagi antenna structures, hybrids of these and/or other types of antenna structures, etc. Different radiators  30  may be used to cover different frequency bands or the same antennas may be used to cover different frequency bands if desired. Radiators  30  and one or more transceivers  28  may transmit and/or receive radio-frequency signals (e.g., radio-frequency signals that convey wireless data) with another communication terminal in communications system  12  over a corresponding wireless link (e.g., using links such as links  16 ,  18 ,  14 , and/or  20  of  FIG.  1   ). Radiators  30  and transceivers  28  may be used to concurrently convey wireless data with multiple external communication terminals over multiple separate wireless links (e.g., communication terminal  10  may maintain multiple wireless links with other communication terminals at any given time). 
     Input-output circuitry  24  may include other input-output devices if desired. Input-output devices may be used to allow data to be supplied to communication terminal  10  and to allow data to be provided from communication terminal  10  to external devices (communication terminals). These input-output devices may include data port devices, user interface devices, and other input-output components. For example, input-output devices in communication terminal  10  may include displays (e.g., touch screens or displays without touch sensitivity), keyboards, touch pads, key pads, buttons, scrolling wheels, joysticks, cameras, infrared sensors, microphones, speakers, light sources, status indicators, audio jacks, accelerometers or other motion sensors, a compass, proximity sensors, magnetic sensors, capacitance sensors, and any other desired sensors and/or input-output components. 
     Communication terminal  10  may also include other structures  32 . Other structures  32  may include support structures such as a housing (e.g., a housing having walls formed from metal and/or dielectric materials), radome, frame, enclosure, chassis, case, wheels, windows, etc. Other structures  32  may include power source devices, solar panels for generating electricity to power wireless circuitry  26  (e.g., in scenarios where communication terminal  10  of  FIG.  2    forms communication terminal  10 A of  FIG.  1   ), propulsion systems, etc. 
     Any desired antenna structures may be used for implementing radiators  30 . In one suitable arrangement that is sometimes described herein as an example, patch antenna structures may be used for implementing radiators  30 . Radiators  30  that are implemented using patch antenna structures may sometimes be referred to herein as patch antenna radiators. An illustrative patch antenna radiator that may be used in communication terminal  10  is shown in  FIG.  3   . 
     As shown in  FIG.  3   , radiator  30  may have a patch antenna resonating element  34  that is separated from and parallel to a ground plane such as antenna ground plane  36  (sometimes referred to herein as ground  36  or antenna ground  36 ). Patch antenna resonating element  34  may lie within a plane such as the X-Y plane of  FIG.  3    (e.g., the lateral surface area of element  34  may lie in the X-Y plane). Patch antenna resonating element  34  may sometimes be referred to herein as patch  34 , patch element  34 , patch resonating element  34 , antenna resonating element  34 , or resonating element  34 . Ground plane  36  may lie within a plane that is parallel to the plane of patch element  34 . Patch element  34  and ground plane  36  may therefore lie in separate parallel planes that are separated by a fixed distance. Patch element  34  and ground plane  36  may be formed from conductive traces patterned on a dielectric substrate such as ceramic, a rigid printed circuit board substrate, or a flexible printed circuit substrate. 
     The length of the sides of patch element  34  may be selected so that radiator  30  resonates (radiates) at a desired operating frequency. For example, the sides of patch element  34  may each have a length  38  that is approximately equal to half of the wavelength of the signals conveyed by radiator  30  (e.g., the effective wavelength given the dielectric properties of the materials surrounding patch element  34 ). The example of  FIG.  3    is merely illustrative. Patch element  34  may have a square shape in which all of the sides of patch element  34  are the same length or may have a different rectangular shape. Patch element  34  may be formed in other shapes having any desired number of straight and/or curved edges. In another suitable arrangement, patch element  34  may have a circular or elliptical shape. If desired, patch element  34  and ground plane  36  may have different shapes and relative orientations. 
     To enhance the polarizations handled by radiator  30 , radiator  30  may be provided with multiple feeds. As shown in  FIG.  3   , radiator  30  may have a first feed (port) that is coupled to a first transmission line path  42  such as transmission line path  42 A and a second feed (port) that is coupled to a second transmission line path  42  such as transmission line path  42 B. The first feed may have a first ground feed terminal coupled to ground plane  36  (not shown in  FIG.  3    for the sake of clarity) and a first positive feed terminal  40 A coupled to patch element  34 . The second feed may have a second ground feed terminal coupled to ground plane  36  (not shown in  FIG.  3    for the sake of clarity) and a second positive feed terminal  40 B on patch element  34 . Transmission line paths  42 A and  42 B may include coaxial cable paths, microstrip transmission lines, stripline transmission lines, edge-coupled microstrip transmission lines, edge-coupled stripline transmission lines, waveguide structures for conveying signals at millimeter wave frequencies (e.g., coplanar waveguides, grounded coplanar waveguides, or substrate integrated waveguides), transmission lines formed from combinations of transmission lines of these types, etc. Transmission line paths  42 A and  42 B may sometimes be referred to herein as transmission lines or radio-frequency transmission lines. 
     Holes, slots, or other openings may be formed in ground plane  36  to allow radio-frequency signals to be transmitted from one side of the ground plane to the other. In one suitable arrangement, transmission lines  42 A and  42 B may pass from below ground plane  36  to positive feed terminals  40 A and  40 B. In another suitable arrangement, radio-frequency signals are coupled onto the patch element wirelessly through slots or holes (e.g., the patch element may be indirectly fed). When using the first feed associated with positive feed terminal  40 A, radiator  30  may transmit and/or receive radio-frequency signals having a first polarization (e.g., the electric field of the radiated signals generated by antenna current conveyed through positive feed terminal  40 A may be oriented parallel to the Y-axis in  FIG.  3   ). When using the feed associated with positive feed terminal  40 B, radiator  30  may transmit and/or receive radio-frequency signals having a second orthogonal polarization (e.g., the electric field of the radiated signals generated by antenna current conveyed through positive feed terminal  40 B may be oriented parallel to the X-axis of  FIG.  3    so that the polarizations associated with positive feed terminals  40 A and  40 B are orthogonal to each other). 
     One of positive feed terminals  40 A and  40 B may be used at a given time so that radiator  30  operates as a single-polarization radiator or both positive feed terminals may be operated at the same time with controlled phasing between the two feeds so that radiator  30  operates with other polarizations (e.g., as a dual-polarization radiator, a circularly-polarized radiator, an elliptically-polarized radiator, etc.). If desired, the active feed may be changed over time so that radiator  30  can switch between covering vertical or horizontal polarizations at a given time. Positive feeds terminals  40 A and  40 B may be coupled to different phase and magnitude controllers or may both be coupled to the same phase and magnitude controller. If desired, positive feed terminals  40 A and  40 B may both be operated with the same phase and magnitude at a given time (e.g., when radiator  30  acts as a dual-polarization radiator). If desired, the phases and magnitudes of radio-frequency signals conveyed over positive feed terminals  40 A and  40 B may be controlled separately and varied over time so that radiator  30  exhibits other polarizations (e.g., circular or elliptical polarizations). The example of  FIG.  3    is merely illustrative. Radiator  30  may have any desired number of feeds. Other types of antenna structures may be used if desired. 
     For long-distance wireless communications links such as links  16 ,  14 ,  18 , and  20  of  FIG.  1   , radiators  30  may need to operate with a relatively high gain in order to maintain satisfactory wireless link quality with external communications terminals (e.g., communications terminals located tens, hundreds, or thousands of miles away from communication terminal  10 ). In order to boost the gain handled by radiators  30  in a particular direction (e.g., towards external communications terminals), in some scenarios, the radiators are arranged in a phased antenna array.  FIG.  4    shows an example of how multiple radiators  30  in communication terminal  10  may be arranged in a phased antenna array. As shown in  FIG.  4   , phased antenna array  53  may be coupled to signal paths such as transmission lines  42  (e.g., one or more radio-frequency transmission lines for covering one or more polarizations). For example, a first radiator  30 - 1  in phased antenna array  53  may be coupled to a first transmission line  42 - 1 , a second radiator  30 - 2  in phased antenna array  53  may be coupled to a second transmission line  42 - 2 , an Mth radiator  40 -M in phased antenna array  53  may be coupled to an Mth transmission line  42 -N, etc. 
     A corresponding transceiver chain  46  is coupled to each transmission line  42  (e.g., transceiver chain  46 - 1  is coupled to transmission line  42 - 1 , transceiver chain  46 - 2  is coupled to transmission line  42 - 2 , transceiver chain  46 -M is coupled to transmission line  42 -M, etc.). Each transceiver chain  46  includes a corresponding phase shifter  48 , amplifier  50 , and transceiver  28  (e.g., first chain  46 - 1  includes phase shifter  48 - 1  and amplifier  50 - 1 , second chain  46 - 2  includes phase shifter  48 - 2  and amplifier  50 - 2 , etc.). While the example of  FIG.  4    only shows amplifiers  50  in a single direction (e.g., for transmitting signals) for the sake of clarity, in general, transceiver chains  46  may also include amplifiers  50  in an opposing direction (e.g., low noise amplifiers pointing towards transceivers  28  for receiving signals). Transceiver chains  46  are coupled to baseband processor  44 . Baseband processor  44  is coupled to other components (e.g., an applications processor) over data path  58 . Baseband processor  44  may convey baseband data for transmission to transceivers  28 . Transceivers  28  may convey received baseband signals to baseband processor  44 . 
     During signal transmission operations, transmission line paths  42  may be used to supply signals (e.g., radio-frequency signals such as millimeter wave and/or centimeter wave signals) from transceiver circuitry  28  (e.g., transceivers  28 - 1  through  28 -M) to radiators  30  for wireless transmission to an external communication terminal. During signal reception operations, transmission line paths  42  may be used to convey signals received by radiators  30  from the external communication terminal to transceivers  28 - 1  through  28 -M. 
     The use of multiple radiators  30  in phased antenna array  53  allows beam steering arrangements to be implemented by controlling the relative phases and magnitudes (amplitudes) of the radio-frequency signals conveyed by the radiators. Phase shifters  48  may adjust the relative phases and/or amplifiers  50  may adjust the relative magnitudes of the transmitted and received radio-frequency signals. The term “beam” or “signal beam” may be used herein to collectively refer to wireless signals that are transmitted and received by at least one radiator  30  in a particular direction. The beam exhibits a peak gain in a pointing direction (e.g., at a pointing angle) and some reduced gain away from the pointing direction (e.g., the beam may exhibit a beam width associated with the physical spread of the electromagnetic energy associated with the signals). The term “transmit beam” may sometimes be used herein to refer to a signal beam of transmitted radio-frequency signals whereas the term “receive beam” may sometimes be used herein to refer to a signal beam of received radio-frequency signals. 
     Phased antenna array  53  operates by concurrently transmitting or receiving radio-frequency signals using each radiator in the array while providing the signals for each radiator with predetermined phases and magnitudes. If, for example, phase shifters  48  and amplifiers  50  are adjusted to produce a first set of phases and magnitudes for transmitted radio-frequency signals, the signals transmitted by each radiator will constructively and destructively interfere during propagation to form a combined transmit beam that is oriented in direction  52 . If, however, phase shifters  48  and amplifiers  50  are adjusted to produce a second set of phases and magnitudes for the transmitted radio-frequency signals, the signals transmitted by each radiator will constructively and destructively interfere to form a combined transmit beam that is oriented in direction  54 . Similarly, if phase shifters  48  and amplifiers  50  are adjusted to produce the first set of phases and/or magnitudes, wireless signals may be received from direction  52 . If phase shifters  48  and amplifiers  50  are adjusted to produce the second set of phases and magnitudes, signals may be received from direction  54 . By adjusting the phase and magnitude of each transmit chain  46 - 1 , the relative phases and magnitudes of the signals transmitted (or received) by each radiator is changed to shift (steer) the direction of the beam of signals handled by phased antenna array  53 . In this way, phased antenna array  53  may steer the signal beam over field of view  56  (e.g., to point towards a single external communication terminal). 
     Phased antenna arrays such as phased antenna array  53  of  FIG.  4    require separate amplifiers  50 , transceivers  28 , and phase shifters  48  for each radiator  30  to point the signal beam in only a single direction at any given time. This may consume an excessive amount of power and space within communication terminal  10 . These factors are particularly pronounced in scenarios where communication terminal  10  needs to communicate with multiple external communication terminals at once. In these scenarios, separate phased antenna arrays (e.g., phased antenna arrays each having M radiators, M phase shifters, M amplifiers, and M transceivers) may be required to maintain each wireless link with each external communication terminal. In order to reduce or minimize power and space consumption within communication terminal  10  while supporting multiple wireless communications links with satisfactory link quality, communication terminal  10  may be provided with wireless circuitry of the type shown in  FIG.  5   . 
     As shown in  FIG.  5   , wireless circuitry  26  may include N antenna modules  68  (e.g., a first antenna module  68 - 1 , a second antenna module  68 - 2 , an Nth antenna module  68 -N, etc.). Each antenna module  68  (sometimes referred to herein as tile  68 , module tile  68 , or module  68 ) may include K radiators  30  (e.g., a first radiator  30 - 1 , a second radiator  30 - 2 , a Kth radiator  30 -K). The K radiators  30  in each module  68  may be coupled to a single corresponding (shared) one of N transceiver chains  60  (e.g., a first transceiver chain  60 - 1 , a second transceiver chain  60 - 2 , an Nth transceiver chain  60 -N, etc.). For example, each radiator  30  in module  68 - 1  may be coupled to transceiver chain  60 - 1  over a corresponding transmission line  42  (e.g., radiator  30 - 1  may be coupled to chain  60 - 1  over transmission line  42 - 1 , radiator  30 - 2  may be coupled to chain  60 - 1  over transmission line  42 - 2 , radiator  30 -K may be coupled to chain  60 - 1  over transmission line  42 -K, etc.). Similarly, each radiator  30  in module  68 - 2  may be coupled to transceiver chain  60 - 2  and each radiator  30  in module  68 -N may be coupled to transceiver chain  60 -N. 
     Each transceiver chain  60  includes a corresponding transceiver  28 , amplifier  64 , and phase shifter  62  (e.g., chain  60 - 1  may include transceiver  28 - 1 , amplifier  64 - 1 , and phase shifter  62 - 1 , chain  60 - 2  may include transceiver  28 - 2 , amplifier  64 - 2 , and phase shifter  62 - 2 , chain  60 -N may include transceiver  28 -N, amplifier  64 -N, and phase shifter  62 -N, etc.). The transceiver  28  in each chain may be coupled to one or more baseband processors  44  (e.g., a single shared baseband processor  44  or multiple separate baseband processors  44 ). Baseband processor(s)  44  may be coupled to other circuitry such as applications processor circuitry (e.g., control circuitry  22  of  FIG.  2   ) over data path  58 . While the example of  FIG.  5    only shows amplifiers  64  in a single direction (e.g., for transmitting signals) for the sake of clarity, in general, transceiver chains  60  may also include amplifiers  64  in an opposing direction (e.g., low noise amplifiers pointing towards transceivers  28  for receiving signals). 
     Amplifiers  64  of  FIG.  5    may include both power amplifiers for amplifying transmitted signals and low noise amplifiers for amplifying received signals. Filter circuitry (not shown) may be interposed on chains  60  to separate transmitted and received signals if desired. In the example of  FIG.  5   , phase shifters  62  are shown as being coupled between amplifiers  64  and radiators  30 . This is merely illustrative and, if desired, amplifiers  64  may be coupled between phase shifters  62  and radiators  30  or may be omitted. In scenarios where radiators  30  have multiple feed terminals (e.g., both feed terminals  40 A and  40 B of  FIG.  3   ), each transceiver  28  may include a first port coupled to feed terminals  40 A and a second port coupled to feed terminals  40 B (e.g., over the same amplifier, phase shifter, and switching circuitry or over separate amplifiers, phase shifters, and switching circuitry). 
     Each radiator  30  in each module  68  is coupled to its transceiver chain  60  through a corresponding switch  72  (e.g., radiator  30 - 1  in module  68 - 1  may be coupled to chain  60 - 1  through switch  72 - 1 , radiator  30 - 2  may be coupled to chain  60 - 1  through switch  72 - 2 , radiator  30 -K may be coupled to chain  60 - 1  through switch  72 -K, etc.). While switches  72  are shown as separate components in  FIG.  5   , two or more of switches  72  may be formed from the same switching circuitry (e.g., a switch matrix or switching network of any desired switches arranged in any desired manner). Baseband processor(s)  44  or other control circuitry in communication terminal  10  (e.g., control circuitry  22  of  FIG.  2   ) may provide control signals to control terminals on switches  72  that selectively turn the switches on or off. 
     When a given switch  72  is turned on (closed or activated), the associated radiator  30  is activated (enabled) by coupling the radiator  30  to the corresponding transceiver chain  60 . The activated radiator  30  subsequently transmits radio-frequency signals provided by the corresponding transceiver  28  and/or provides received radio-frequency signals to the corresponding transceiver  28 . When a given switch is turned off (opened or deactivated), the associated radiator  30  is deactivated (disabled) by decoupling the radiator  30  from transceiver chain  60 . 
     Each antenna module  68  may include a corresponding radio-frequency lens structure such as dielectric lens  66 . Dielectric lenses  66  may be placed over the radiators in each antenna module  68  for directing the radio-frequency signals conveyed by that module. For example, a first dielectric lens  66 - 1  may be placed over (e.g., overlapping or in alignment with) antenna module  68 - 1 , a second dielectric lens  66 - 2  may be placed over antenna module  68 - 2 , an Nth lens  66 -N may be placed over antenna module  68 -N, etc. Lenses  66  may have a dielectric constant and shape that serves to alter the impedance over each radiator  30  by different amounts in different directions (e.g., based on the geometry of lens  66  and the location of each radiator  30  relative to lens  66 ). This may serve to direct or shift the radio-frequency signals conveyed by each underlying radiator  30  in a different direction. 
     As shown in the example of  FIG.  5   , switches  72 - 1  and  72 -K may be turned on to couple radiators  30 - 1  and  30 -K to transceiver chain  60 - 1 . Transceiver  28 - 1  provides the same radio-frequency signals (e.g., with the same phase as provided by phase shifter  62 - 1  and the same magnitude as provide by amplifier  64 - 1 ) to both radiators  30 - 1  and  30 -K. Radiator  30 - 1  may generate a transmit beam  80 . The local geometry of lens  66 - 1  over radiator  30 - 1  may serve to redirect beam  80  in direction  78 . At the same time, radiator  30 -K may generate transmit beam  74 . The local geometry of lens  66 - 1  over radiator  30 -K may serve to redirect beam  74  in direction  76 . By selectively activating different radiators  30  in module  68 - 1 , radio-frequency signals can be transmitted and received by module  68 - 1  in one or more desired directions (e.g., directions pointing towards other communications terminals). In other words, the signal beams conveyed by module  68 - 1  may be steered by selectively activating different radiators  30  rather than by independently adjusting the phase and magnitude of each radiator. Multiple radiators  30  in module  68 - 1  may be activated at once and each beam may concurrently support separate wireless communications links between transceiver  28 - 1  and different respective communication terminals (e.g., radiator  30 -K may perform wireless communications with a first communication terminal in direction  76  using beam  74  while radiator  30 - 1  performs wireless communications with a second communication terminal in direction  78  using beam  80 ). 
     Similarly, independent wireless links may be established using the other antenna modules  68  in wireless circuitry  26 . For example, switch  72 ′ in module  68 - 2  may be turned on so that radiator  30 ′ transmits radio-frequency signals generated by transceiver  28 - 2  over beam  82  in direction  84  (e.g., a boresight direction of module  68 - 2  and lens  66 - 2 ). At the same time, switch  72 ″ in module  68 -N may be turned on so that radiator  30 ″ transmits radio-frequency signals generated by transceiver  28 -N over beam  86  in direction  88 . Similar operations may also be performed to receive wireless signals over corresponding beams pointed in different directions (e.g., to perform bi-directional communications using multiple radiators within each module and/or multiple modules with one or more external communications terminals). 
     In this way, each antenna module may be controlled to establish one or more concurrent wireless links using signal beams (e.g., spot beams) in one or more different directions (e.g., each antenna module may support up to twenty or more concurrently wireless links). Concurrent wireless links may be established within each antenna module and/or across antenna modules so that wireless circuitry  26  may concurrently communicate with any desired number of other communications terminals (e.g., two communication terminals, tens of communication terminals, twenty or more communication terminals, hundreds of communication terminals, thousands of communication terminals, etc.). The geometry of lenses  66  may allow the radio-frequency signals to be conveyed in different pointing directions with a sufficient gain to support wireless communications over the long distances associated with satellite communications networks. 
     In the arrangement of  FIG.  4   , each radiator is concurrently active and provided with an independent phase and magnitude to point a single beam in a desired direction. In contrast, in the arrangement of  FIG.  5   , the radiators  30  in each module  68  share the same transceiver chain  60  and are provided with the same phase and magnitude. Rather than using relative phases between each radiator to steer a single beam of signals, one or more radiators  30  are independently activated to produce a beam of signals in one or more desired directions (e.g., through a single corresponding lens  66 ). Sharing transceiver chains between each antenna module  68  in this way (e.g., rather than providing separate transceiver chains for each radiator) reduces the space and power required to operate wireless circuitry  26  relative to the arrangement of  FIG.  4   . By activating radiators within each antenna module and across antenna modules, wireless circuitry  26  may communicate with many other communications terminals at any given time with satisfactory link quality (e.g., tens of terminals, hundreds of terminals, etc.). 
     The N antenna modules  68  in wireless circuitry  26  may sometimes be collectively referred to herein as an array  70  of antenna modules  68 . The radiators  30  within each module  68  may sometimes be referred to herein as sub-arrays of array  70 . The antenna modules  68  in array  70  may be arranged in any desired pattern (e.g., a grid having rows and columns of modules or having other patterns of modules such as hexagonal patterns of modules). There may be any desired number N of modules  68  in array  70  (e.g., one module  68 , two modules  68 , three modules  68 , four modules  68 , more than four modules  68 , eight modules  68 , nine modules  68 , sixteen modules  68 , twenty-five modules  68 , etc.). In general, the number N of modules  68  in array  70  may be less than or equal to the number M of radiators  30  in the arrangement of  FIG.  4   , thereby serving to reduce the overall power consumption by the transceiver chains in wireless circuitry  26  relative to the arrangement of  FIG.  4   . Each module  68  may include any desired number K of radiators  30  (e.g., one radiator  30 , two radiators  30 , three radiators  30 , four radiators  30 , nine radiators  30 , twelve radiators  30 , sixteen radiators  30 , twenty-five radiators  30 , sixty-four radiators  30 , greater than four radiators  30 , greater than sixty-four radiators  30 , etc.). The radiators  30  in each module  68  may be arranged in any desired pattern (e.g., a rectangular grid of rows and columns, concentric rings, or other patterns). 
       FIG.  6    is a cross-sectional side view of antenna module  68 - 1  in array  70 . As shown in  FIG.  6   , antenna module  68 - 1  may include a substrate such as substrate  90 . Substrate  90  may be a rigid printed circuit substrate, a flexible printed circuit substrate, ceramic, glass, plastic, or any other desired substrate. Ground plane  36  for each radiator  30  may be embedded within substrate  90  (e.g., on one or more layers of substrate  90 ). Patch elements  34  of each radiator  30  may be located at the upper surface of substrate  90  and may be coupled to switching circuitry  92  mounted to the lower surface of substrate  90  over transmission line traces  95 . Transmission line traces  95  may be used in forming transmission lines  42  ( FIG.  5   ) and may include stripline transmission line structures, microstrip transmission line structures, waveguide transmission line structures, conductive through vias extending through substrate  90 , conductive traces on one or more layers of substrate  90 , etc. Switching circuitry  92  may include surface mount components or other components used to implement the K switches  72  of  FIG.  5   . As shown in  FIG.  6   , transceiver  28 - 1  may also be mounted to the lower surface of substrate  90  (e.g., as a radio-frequency integrated circuit) and may be coupled to switching circuitry  92  over conductive traces or other transmission line structures on substrate  90 . Phase shifter  62 - 1  and amplifier  64 - 1  ( FIG.  5   ) may be integrated within the integrated circuit used to form transceiver  28 - 1 , if desired. Transceiver  28 - 1  may be coupled to baseband processor(s)  44  of  FIG.  5    over baseband path  94 . 
     As shown in  FIG.  6   , lens  66 - 1  of antenna module  68 - 1  may be mounted to the upper surface of substrate  90  over patch elements  34 . Lens  66 - 1  may completely overlap each of the K patch elements  34 , may partially overlap some of the patch elements (e.g., patch element  34 - 1  as shown in  FIG.  6   ), and/or may not overlap some of the patch elements (e.g., patch element  34 -K as shown in  FIG.  6   ). Lens  66 - 1  may be affixed to substrate  90  using any desired attachment structures (e.g., a layer of adhesive, screws, pins, clips, brackets, etc.). Lens  66 - 1  may serve to direct the beam of signals for each radiator  30  in module  68 - 1  in a different respective direction. In the example of  FIG.  6   , lens  66 - 1  has a hemispheric shape. This is merely illustrative. In general, lens  66 - 1  may have any other desired shape having curved and/or flat sides (e.g., lens  66 - 1  may have an aspherical shape, a freeform shape, a spherical shape, a conical shape, a cylindrical shape, combinations of these, etc.). Likewise, the lens may have a uniform effective dielectric constant throughout its structure or may have a spatially varying dielectric constant. Using a spatially varying dielectric constant may, for example, allow the lens to have a flat shape. As an example, a flat lens may be formed using multiple materials having varying base dielectric constants or by mixing two or more materials (e.g., air and plastic) while varying their ratios. Similar structures may be used to form the other antenna modules  68  in array  70 . 
       FIG.  7    is a top-down view showing one example of how antenna modules  68  may be arranged in array  70 . As shown in  FIG.  7   , array  70  may include four or more modules  68  (e.g., modules  68 - 1 ,  68 - 2 ,  68 - 3 , and  68 - 4 ) that each include a corresponding array of patch elements  34  (radiators  30 ) and a corresponding lens  66 . Each module  68  in array  70  may be provided with the same number of patch elements and the same lens  66  or two or more of modules  68  in array  70  may be provided with a different number or arrangement of patch elements and/or different lenses  66  (e.g., lenses  66  having different shapes). Varying the orientation and position of patch elements  34  across array  70  and/or varying the location of lenses  66  relative to the underlying elements  34  across array  70  may, for example, serve to reduce side lobe gain for the signals conveyed by array  70 . 
     The patch elements  34  in each module  68  may be separated from adjacent patch elements  34  by at least distance  96 . In phased antenna arrays such as phased antenna array  53  of  FIG.  4   , each patch element needs to be separated by a lattice spacing of no more than about one-half of the wavelength of operation (e.g., approximately 12 mm for K u  band frequencies or approximately 6 mm for K a  band frequencies). This leaves relatively little space between patch elements to integrate patch elements for covering other frequencies. However, the patch elements  34  in antenna modules  68  need not be located as close together (e.g., because the patch elements  34  in each module are all provided with signals having the same phase and magnitude and steering is performed by simply activating each radiator and directing the signals using lens  66 ). In other words, distance  96  may be greater than or equal to one-half of the wavelength of operation of module  68  (e.g., greater than 6 mm, greater than 12 mm, etc.). This may, for example, allow sufficient space between adjacent patch elements  34  on module  68  for covering a first frequency band to accommodate additional radiators for covering a second frequency band. 
     In the example of  FIG.  7   , patch elements  34  in each module  68  are arranged in a rectangular grid of rows and columns. This is merely illustrative. In practice, lenses  66  may exhibit circular symmetry (e.g., to accommodate circular polarizations handled by patch elements  34 ). The arrangement of patch elements  34  need not have the same symmetry. To break that symmetry, a Cartesian grid of patch elements may be defined for a given module, which is then rotated in-plane by an angle other than 90 degrees in subsequent neighboring modules  68 . In another suitable arrangement, patch elements  34  may be arranged in a pattern of concentric rings. If an antenna module is designed with patch elements arranged in concentric rings such that when the module is rotated by 90, 180, and 270 degrees the patches are all located in different positions relative to the axis of rotation, a diversity of patch element positions may result. The lens, in this example, is assumed to be centered over the axis of rotation, and thus there is an increase in number of relative patch positions. This in turn improves aggregate scan performance by introducing diversity into scanning locations at the individual module level. It prevents side lobes from each individual module from summing across the modules as the modules are arrayed and rotated. In one suitable arrangement, array  70  may include four identical modules each rotated at one of these four distinct angles (e.g., 0, 90, 180, and 270 degrees). This may, for example, allow the array to exhibit more robust polarization performance (e.g., circular polarization performance) than in scenarios where all of the patch elements have the same orientation across the array.  FIG.  8    is a top-down view showing how array  70  may include modules  68  that have patch elements  34  arranged in a pattern of concentric rings and that are rotated with respect to each other across the array. 
     As shown in  FIG.  8   , array  70  may include antenna modules such as modules  68 - 1  and  68 - 2 . Modules  68 - 1  and  68 - 2  may each include patch elements  34  arranged in one or more concentric rings  100  centered about a central axis (e.g., an axis extending parallel to the Z-axis of  FIG.  8   ). In the example of  FIG.  8   , module  68 - 1  includes patch elements  34  arranged in first, second, and third concentric rings  100 - 1 ,  100 - 2 , and  100 - 3  about axis  102  whereas module  68 - 2  includes first, second, and third concentric rings  100 - 1 ,  100 - 2 , and  100 - 3  of patch elements  34  centered about axis  104 . Each ring may include any desired number of patch elements  34  (e.g., rings that are located farther from the central axis may include more patch elements than rings closer to the central axis). Arranging patch elements  34  in circular rings may, for example, allow the patch elements to exhibit circular symmetry similar to that of lenses  66 . 
     If desired, the patch elements  34  in module  68 - 2  (e.g., rings  100 - 1 ,  100 - 2 , and  100 - 3  in module  68 - 2 ) may be rotated at a predetermined angle (e.g., 30 degrees, 45 degrees, 90 degrees, 60 degrees, 120 degrees, etc.) with respect to the corresponding patch elements  34  (rings  100 ) in module  68 - 1 , as shown by arrow  98 . As an example, each patch element  34  in ring  100 - 2  of module  68 - 1  may be placed at 0 degrees, 45 degrees, 90 degrees, etc. relative to the X-axis about central axis  102 , whereas each patch element  34  in ring  100 - 2  of module  68 - 2  may be placed at 30 degrees, 75 degrees, 120 degrees, etc. relative to the X-axis. Orienting the patch elements  34  in adjacent modules  68  in this way may, for example, create more scan positions in the global coordinate system relative to scenarios where the patch elements  34  in each module  68  are arranged in the same orientation, while also allowing each antenna module  68  to be fabricated using the same fabrication processes. In the example of  FIG.  8   , lenses  66  are centered about axes  102  on modules  68 . In another suitable arrangement, lenses  66  may be offset with respect to the center of the underlying module  68  by different amounts across array  70  to introduce positional diversity across the array. In yet another suitable arrangement, each patch element  34  may be sequentially rotated (e.g., by 90 degrees) with respect to the other patch elements  34  within the same module  68 . This may, for example, optimize performance while reducing side lobes in scenarios where patch elements  34  are driven using circularly polarized signals. 
       FIG.  9    is a top-down view showing an example of how four modules  68  in array  70  may be formed using the same structures (e.g., using the same lenses and radiators) but may be oriented at different angles with respect to each other. As shown in  FIG.  9   , array  70  may include modules  68 - 1 ,  68 - 2 ,  68 - 3  and  68 - 4 . Each of these modules may be provided with the same pattern of patch elements  34  and lenses  66 . However, module  68 - 2  may be rotated at a non-zero angle with respect to module  68 - 1 , module  68 - 3  may be rotated at a non-zero angle with respect to modules  68 - 1  and  68 - 2 , and module  68 - 4  may be rotated at a non-zero angle with respect to modules  68 - 1 ,  68 - 2 , and  68 - 3 . Arrows  101  illustrate the relative orientations of modules  68 - 1 ,  68 - 2 ,  68 - 3 , and  68 - 4  in  FIG.  9   . For example, module  68 - 1  may be rotated at 0 degrees with respect to the X-axis, module  68 - 2  may be rotated at 90 degrees with respect to the X-axis, module  68 - 3  may be rotated at 270 degrees with respect to the X-axis, and module  68 - 4  may be rotated at 180 degrees with respect to the X-axis. 
     This may, for example, provide array  70  with a diversity of patch element positions. This may serve to improve aggregate scan performance by introducing diversity into scanning locations at the individual module level. It also allows prevents side lobes from each individual module from summing across the modules as the modules are arrayed and rotated. This may, for example, allow for array  70  to exhibit more robust polarization performance (e.g., circular polarization performance) than in scenarios where all of the patch elements have the same orientation across the array. If desired, each of antenna modules  68 - 1 ,  68 - 2 ,  68 - 3 , and  68 - 4  may be provided with radio-frequency signals (e.g., from the corresponding transceiver chains) that have been offset in phase based on the orientation (rotation angle) of the module and the distances between the modules (e.g., beam steering performed across array  70  may involve providing different phase offsets to each of modules  68 - 1 ,  68 - 2 ,  68 - 3 , and  68 - 4  to compensate for their respective orientations and separations, in addition to phasing the modules to steer a signal beam in a particular direction). The example of  FIG.  9    is merely illustrative. Patch elements  34  in modules  68 - 1 ,  68 - 2 ,  68 - 3 , and  68 - 4  may be arranged in other patterns (e.g., concentric rings, non-rectangular patterns, etc.). 
     If desired, the relative phases and magnitudes provided to each antenna module  68  (e.g., by the corresponding transceiver chain  60 ) may be adjusted to perform beam steering across the array  70  (e.g., where each module  68  is independently controlled (phased) like a corresponding radiator  30  in the phased antenna array  53  of  FIG.  4   ).  FIG.  10    is a diagram showing how each antenna module  68  may be controlled to perform beam steering across array  70 . 
     As shown in  FIG.  10   , when patch element  34 ′ is activated (e.g., using switches  72  shown in  FIG.  5   ), patch element  34 ′ and lens  66 - 1  in module  68 - 1  may produce a signal beam  108  in direction  112 . When patch element  34 ″ is activated, patch element  34 ″ and lens  66 - 2  may produce a signal beam  106  in direction  110 . Baseband processor(s)  44  and/or other control circuitry  22  ( FIG.  2   ) may adjust the phases provided by phase shifters  62 - 1  and  62 - 2  (e.g., using control signal  121 ) and/or may adjust the magnitudes provided by amplifiers  64 - 1  and  64 - 2  so that beams  108  and  106  constructively and destructively interfere to produce a combined signal beam pointing in direction  114  (e.g., a direction that is the same as directions  112  and/or  110  or that is different than directions  112  and  110 ). By adjusting the relative phase and magnitude between modules  68 , the combined beam produced by signals from multiple modules  68  may be steered in any desired directions. In other words, array  70  of modules  68  may be operated as a phased array of modules  68 . Array  70  may therefore sometimes be referred to herein as phased array antenna  70 , antenna  70 , or scanning antenna  70 . In general, different combinations of patch elements  34  may be concurrently activated while phase and magnitude are adjusted for each module  68  to produce one or more combined beams (e.g., satellite spot beams) pointing in any desired directions across field of view  122  of array  70  (e.g., directions  116 ,  118 ,  120 , etc.). 
     The combined beam may, for example, be used to point beams in directions that are not otherwise pointed to directly by individual radiators  30  (individual patch elements  34 ) or to increase the gain of array  70  in a particular direction. For example, beams  108  and  106  of  FIG.  10    may each exhibit individual gains of up to 18 dB. In some scenarios, an external communication terminal may require a wireless link with a link budget of 20 dB or higher (e.g., 33 dB). The beam from an individual patch element  34  may not offer sufficient gain to support such a wireless link. However, two or more separate beams from two or more modules  68  may be generated in the same direction (e.g., by activating appropriate patch elements  34  in each module) to produce a combined beam in the direction of the external communication module that exhibits a total gain that meets the required link budget (e.g., the combined beam may be produced at a gain of 33 dB or greater in a scenario where radiators from 32 modules contribute to the combined beam). In this way, each lens  66  may be provided with signals of different phases and magnitudes to point one or more beams of signals in any desired directions with any desired gain (e.g., to meet link budget requirements associated with different external communication terminals). 
       FIG.  11    is a flow chart of illustrative steps that may be performed in operating array  70  of  FIG.  10    as a phased array of antenna modules. At step S 1 , control circuitry  22  ( FIG.  2   ) may identify desired pointing directions for communications (e.g., directions towards external communication terminals). 
     At step S 2 , control circuitry  22  may control switches  72  ( FIG.  5   ) to selectively activate one or more radiators  30  in one or more antenna modules  68  across array  70  based on the identified pointing directions. For example, radiators  30  that produce signal beams in the identified pointing directions may be activated. 
     At optional step S 3 , control circuitry  22  may adjust the phases and magnitudes for each module  68  to generate one or more combined beams using signals from two or more modules  68  based on the desired pointing directions. The combined beams may, for example, be produced in one or more of the identified pointing directions. Control circuitry  22  may, for example, perform step S 3  in scenarios where individual radiators  30  are not capable of covering the desired pointing direction with sufficient gain. Control circuitry  22  may, for example, control array  70  so that different beams pointing in approximately the same direction from two or more antenna modules (e.g., three antenna modules, four antenna modules, sixteen antenna modules, more than sixteen antenna modules, etc.) are combined to produce a combined beam with a sufficient gain in one of the predetermined directions (e.g., to meet a link budget requirement associated with an external communication terminal at the predetermined direction). Step S 3  may be omitted if desired. 
     At step S 4 , wireless circuitry  26  may perform wireless communications over the signal beams generated by individually activated radiators  30  and/or over combined signal beams generated by multiple activated radiators  30  across two or more modules  68  (e.g., over corresponding wireless links such as links  14 ,  18 ,  16 , and  20  of  FIG.  1   ). The example of  FIG.  11    is merely illustrative. The steps of  FIG.  11    may be performed in other orders (e.g., step S 3  may be performed prior to or concurrently with step S 2 ). If desired, control circuitry  22  may sweep through different beams (e.g., by activating individual radiators  30  and/or by adjusting phases across modules) until a communications link with an external communication terminal is found and/or established. 
     Forming array  70  using modular structures such as antenna modules  68  may allow array  70  to be arranged in a non-planar shape if desired.  FIG.  12    is a side-view showing how array  70  of modules  68  may be provided with a non-planar shape. As shown in  FIG.  12   , array  70  may be curved around the Y-axis of  FIG.  12    (e.g., so that each module  68  faces a different direction). This may allow array  70  to fit within terminal  10  while accommodating other components such as curved components  124  and/or  126  (e.g., a curved housing, etc.). This may also serve to expand the field of view  128  of array  70  relative to scenarios where array  70  is planar, for example. The example of  FIG.  12    is merely illustrative. In general, array  70  may have any desired shape. Array  70  may be curved around multiple axes (e.g., around both the X and Y axes of  FIG.  12   ) to form a surface of any desired shape. 
     If desired, radiators  30  in each module  68  may be used to cover multiple different frequency bands.  FIG.  13    is a diagram of an illustrative module  68 - 1  that may be used to cover multiple different frequency bands. As shown in  FIG.  13   , antenna module  68 - 1  may include different transceiver chains  60 - 1  that each cover a respective frequency band (e.g., antenna module  68 - 1  may include transceiver chain  60 - 1 A that covers a first frequency band A and transceiver chain  60 - 1 B that covers a second frequency band B). In one suitable arrangement, frequency band A may be a K a  frequency band whereas frequency band B may be a K u  frequency band. Any other bands may be used if desired. 
     As shown in  FIG.  13   , transceiver chain  60 - 1 A includes a corresponding transceiver  28 - 1 A, amplifier  64 - 1 A, and phase shifter  62 - 1 A coupled to each of the K switches  72  of module  68 - 1 . Similarly, transceiver chain  60 - 1 B includes a corresponding transceiver  28 - 1 B, amplifier  64 - 1 B, and phase shifter  62 - 1 B coupled to each of the K switches  72  in module  68 - 1 . Each switch  72  may be controlled to selectively couple each radiator  30  to a selected one of transceiver chains  60 - 1 A and  60 - 1 B at any given time (or to decouple radiator  30  from both chains when that radiator is inactive). This may allow each radiator  30  to convey radio-frequency signals in either frequency band A (e.g., the K a  band) or frequency band B (e.g., the K u  band) in its corresponding pointing direction at any given time. The band covered by each radiator may be changed over time using switches  72 . Each module  68  may include respective transceiver chains such as chains  60 - 1 A and  60 - 1 B of  FIG.  13    for covering different frequency bands (e.g., each module  68  may include a single chain shared by each of the radiators per frequency band). 
     The example of  FIG.  13    is merely illustrative. In general, module  68 - 1  may include any desired number of transceiver chains  60 - 1  coupled to switches  72  (e.g., one transceiver chain per frequency band or per wireless data stream). The example of  FIG.  13    assumes that radiators  30  exhibit sufficient bandwidth to cover each frequency band. In another suitable arrangement, each module  68  may include different radiators for covering different frequency bands. 
       FIG.  14    is a diagram showing how module  68 - 1  may include different radiators for covering different frequency bands. As shown in  FIG.  14   , module  68 - 1  may include a first set of radiators  30 H for covering frequency band A and a second set of radiators  30 L for covering frequency band B. Each radiator  30 H may be coupled to transceiver chain  60 - 1 A over corresponding switches  72 . Each radiator  30 L may be coupled to transceiver  60 - 1 B over corresponding switches  72 . Switches  72  may be selectively activated to provide beams of signals in frequency band A or frequency band B in different directions. Forming radiators  30 H and  30 L as separate radiators may allow each radiator to be optimized for each frequency band. Radiators  30 H may be interspersed among radiators  30 L in module  68 - 1  to allow radiators  30 H and  30 L to cover similar pointing angles. The other modules  68  in array  70  may also include radiators such as radiators  30 H and  30 L for covering different frequency bands. The example of  FIG.  14    is merely illustrative. In general, module  68 - 1  may include any desired number of transceiver chains  60 - 1  and sets of radiators  30  for covering any desired number of frequency bands. 
       FIG.  15    is a perspective view of a given antenna module  68  provided with different sets of radiators for covering different frequency bands. As shown in  FIG.  15   , a first set of patch elements  34 H (e.g., patch elements  34 H in radiators  30 H of  FIG.  14   ) and a second set of patch elements  34 L (e.g., patch elements  34 L in radiators  30 L of  FIG.  14   ) may be mounted to substrate  90 . Patch elements  34 H may be interleaved among patch elements  34 L so that both frequencies may cover similar pointing angles. Patch elements  34 H and  34 L as shown in  FIG.  15    may be repeated to provide module  68  with a rectangular pattern of patch elements (e.g., as shown in  FIG.  7   ) or with concentric circular rings of patch elements (e.g., as shown in  FIG.  8   ). Lens  66  of module  68  has been omitted from  FIG.  15    for the sake of clarity. However, lens  66  may have a lateral outline  130  on the top surface of substrate  90 . Lateral outline  130  may surround each patch element or, as shown in the example of  FIG.  15   , at least one element  34 H and at least one element  34 L may lie outside of outline  130 . 
     Operating modules  68  with multiple frequency bands (e.g., using the arrangements of  FIGS.  13 - 15   ) may allow wireless circuitry  26  to support a greater data throughput per antenna volume relative to flat panel phased antenna arrays (e.g., scenarios where phased antenna array  53  of  FIG.  4    is used). Data throughput may be further increased using multiple different polarizations (e.g., by coupling separate ports on each transceiver  28  to different feed terminals on each radiator such as positive feed terminals  40 A and  40 B of  FIG.  3   ). Signal beams at multiple different frequencies and/or polarizations may be generated in approximately the same pointing direction using multiple different modules  68  to further increase data throughput with a particular external communication terminal at that pointing direction. Beam steering between modules  68  at one or more frequencies may be performed if desired (e.g., as described in connection with  FIGS.  10  and  11   ). In this way, communication terminal  10  may exhibit data throughputs that are up to or at least ten times the data throughput associated with phased antenna array  53  of  FIG.  4   , while also reducing space consumption, power consumption, and manufacturing cost (e.g., while maintaining multiple wireless links with satisfactory link quality over a wide field of view). The example of  FIGS.  6 - 10  and  15    in which radiators  30  include patch elements  34  is merely illustrative. In general, radiators  30  may be formed using any desired antenna structures (e.g., any desired antenna radiating elements having any desired shapes and feeding arrangements). 
     The examples of  FIGS.  5 - 15    in which lenses  66  are shown as having a hemispherical shape are merely illustrative. The shape of lenses  66  in array  70  may be selected to optimize gain for each separately-activated underlying radiator  30  across a desired field of view.  FIG.  16    is a perspective view of a given lens  66  provided with a shape that optimizes radio-frequency performance for modules  68 . 
     As shown in  FIG.  16   , lens  66  may exhibit cylindrical symmetry around central axis  204  (sometimes referred to herein as boresight axis  204 ). Lens  66  may include a hemispherical portion  200  on a base portion such as an underlying tapered (conical) portion  202 . Conical portion  202  may extend from the radius of hemispherical portion  200  to a lesser radius at base lip  208 . Lip  208  may include protruding lips that help stabilize lens  66  on the underlying substrate  90  (not shown). Lip  208  and/or conical portion (base)  202  may be coupled to alignment pins  206  that are received by alignment holes in substrate  90  (e.g., to ensure that lens  66  is aligned with the array of patch elements on the substrate). Lip  208  and/or alignment pins  206  may be omitted if desired. 
     Hemispherical portion  200  of lens  66  may provide a relatively constant effective aperture for the underlying radiators  30 , even for relatively high angles off of the boresight axis. This may, for example, allow for module  68  to communicate with external communication terminals with sufficient link quality over a larger field of view (e.g., communication terminals at higher angles off of the boresight axis) than scenarios where a flat lens is used. Conical portion  202  may serve to reduce the gain of side lobes in the signal beams associated with module  68 . The example of  FIG.  16    is merely illustrative. Conical portion  202  of lens  66  may be cylindrical and other shapes may be used to form lens  66  if desired. 
     Lenses  66  of  FIG.  16    may be provided over each antenna module  68  across array  70 , as shown in the perspective view of  FIG.  17   . As shown in  FIG.  17   , antenna modules  68  and thus lenses  66  may be arranged in a rectangular pattern having rows and columns across array  70 . Each lens  66  may provide a relatively high field of view with satisfactory off-boresight performance (e.g., at 45, 50, 60 degrees or more off boresight) for the corresponding antenna module  68 . Multiple radiators may be activated in each module so that each lens  66  directs multiple beams of signals in one or more frequency bands with satisfactory gain in any desired directions across the field of view of array  70 . Beam steering may be performed across modules  68  and lenses  66  if desired (e.g., as described in connection with  FIG.  10   ). 
       FIG.  18    is a cross-sectional side view of lens  66  for a given antenna module  68 . As shown in  FIG.  18   , lens  66  is mounted to upper surface  210  of substrate  90  in module  68 . Patch elements  34  (e.g., elements  34 - 1 ,  34 - 2 ,  34 - 3 ,  34 - 4 ,  34 - 5 , etc.) may be mounted at surface  210 . This example is merely illustrative and, in general, radiators formed using any desired radiating element structures may be used. Hemispherical portion  200  of lens  66  may have radius R 2 . Conical portion  202  may have an upper end at hemispherical portion  200  with radius R 2  and a lower end at lip  208  with radius R 1 . Lip  208  may extend outward and over one or more patch elements  34 . Lip  208  may be omitted if desired (e.g., conical portion  202  may meet surface  210  of substrate  90  at radius R 1 ). 
     Radius R 1  is less than radius R 2 . This provides conical portion  202  with a tapered profile that extends from hemispherical portion  200  to substrate  90  at angle φ. Angle φ may be determined by radius R 1 , radius R 2 , and height  222  of lens  66 . As examples, angle φ may be between 5 degrees and 45 degrees, between 10 degrees and 30 degrees, less than 30 degrees, greater than 5 degrees, etc.). Radius R 1  may encompass all or some of the patch elements  34  in module  68 . Similarly, radius R 2  may encompass some or all of the patch elements  34  in module  68 . In one suitable arrangement, radius R 1  does not overlap all of the patch elements in module  68  (e.g., radius R 1  may define outline  130  of  FIG.  15   ) whereas radius R 2  overlaps all of the patch elements  34  in module  68  (e.g., the patch element(s) in module  68  located farthest from boresight axis  204  may be located beyond radius R 1  but within radius R 2  from boresight axis  204 ). For example, as shown in  FIG.  18   , patch elements  34 - 1 ,  34 - 2 ,  34 - 4 , and  34 - 5  do not lie within radius R 1  of the boresight axis  204  of lens  66  but do lie within radius R 2  of boresight axis  204 . Radius R 2  may be 30-40 mm, 25-50 mm, 30-60 mm, 20-70 mm, 37-43 mm, 50-150 mm, 10-150 mm, greater than 70 mm, greater than 150 mm, less than 20 mm, or any other desired radius. Radius R 1  may be 20-30 mm, 27-32 mm, 25-35 mm, 10-35 mm, 15-45 mm, 50-150 mm, less than 50 mm, greater than 100 mm, or any other desired radius less than radius R 2 . Height  222  of lens  66  may be 70-80 mm, 73-77 mm, 60-90 mm, 50-100 mm, 100-300 mm, greater than 100 mm, less than 50 mm, or any other desired height that is greater than radius R 2 . In another suitable arrangement, radius R 1  may be between 1 and 4 times the wavelength of operation of the antenna module (e.g., the lowest wavelength of operation in scenarios where the module covers multiple frequencies). The wavelength of operation as used herein may be the free-space wavelength, the guided wavelength, or the effected wavelength in the lens medium (e.g., when adjusted for the dielectric properties of the lens). If desired, a portion of patch elements  34 - 5  and/or  34 - 1  may extend beyond radius R 2  from boresight axis  204 . 
     Lens  66  may be formed from any desired dielectric materials. As examples, lens  66  may be formed from plastic (e.g., acrylonitrile butadiene styrene (ABS) plastic), ceramic, glass, or other desired materials. Hemispherical portion  200  and conical portion (base)  202  may be formed from integral portions of the same piece of dielectric material or hemispherical portion  200  and conical portion  202  may be formed from separate dielectric structures that are attached together (e.g., using adhesive). Hemispherical portion  200  and conical portion  202  may be formed from different dielectric materials if desired. The dielectric constant of the materials used to form lens  66  and the geometry of lens  66  may affect how lens  66  redirects radio-frequency signals. As examples, lens  66  may have a dielectric constant between 2.0 and 4.0, between 2.5 and 3.5, between 2.8 and 3.2, greater than 3.0, greater than 2.5, etc. A dielectric cap such as dielectric cap  216  may be mounted over lens  66 . Dielectric cap  216  may serve to protect lens  66  and may exhibit an intermediate dielectric constant between the dielectric constant of lens  66  and the dielectric constant of the volume surrounding lens  66  (e.g., dielectric cap  216  may serve as an impedance matching layer between lens  66  and free space). This may, for example, serve to reduce internal signal reflections at the lens-free-space interface across a given operating bandwidth. 
     In scenarios where flat lenses are provided over the radiators or where the radiators are implemented in a phased antenna array (e.g., as shown in  FIG.  4   ), the array exhibits a limited gain at relatively high elevation angles θ off of boresight axis  204  due to a reduction in effective aperture at high angles. This is sometimes referred to as cosine loss, because the effective aperture decreases as a function of the cosine of the elevation angle θ off of boresight, leading to a nominal loss of 3 dB (half power) at 60 degrees off boresight and an associated broadening of the radiated beam by a nominal factor of two. Polarization, especially circular polarization, also degrades at high scan angles in flat panel arrays, often requiring complex wide angle impedance matching (WAIM) structures to maintain suitable performance. The geometry of lens  66  may sacrifice some peak boresight gain (e.g., gain at θ=0) in order to recover greater gain at higher angles θ such as 50 degrees or greater. For example, the tapering of conical portion  202  may reduce or eliminate this cosine loss at elevation angles θ greater than 50 degrees off of axis  204 , while also maintaining constant beam width, satisfactory side lobe performance, and polarization. 
     Because lens  66  both enhances directivity of each single radiator (patch element  34 ) and achieves beam scanning by activating only one patch element  34  at a time, multiple position-offset patch elements  34  may be activated simultaneously with reduced or minimal loss in gain for either patch element. In phased antenna arrays provided with flat panel lenses, this would only be possible by allocating half of the aperture to one beam and the other half to the other beam, because the phasing required to beam form is different in two different directions. This leads to nominal gain reduction of 50% for each beam and associated beam broadening and side lobe effects. Lens  66  of  FIG.  18    may allow each beam to remain independent because the radiation from each patch element  34  shares the lens structure without significant interaction, even at the same frequency and in a continuous wave (CW) mode). In other words, two or more patch elements  34  in module  68  may be activated at a given time to direct beams of signals in different directions through lens  66  (e.g., to support concurrent communications links with multiple external communication terminals). 
     The geometry of lens  66  may serve to direct signal beams for patch elements  34  on one side of boresight axis  204  out of lens  66  at an opposing side of boresight axis  204  (e.g., patch elements  34  to the left of boresight axis  204  of  FIG.  18    may convey signals through lens  66  at positive elevation angles θ whereas patch elements to the right of boresight axis  204  convey signals through lens  66  at negative elevation angles θ). In general, patch elements  34  that are located farther from boresight axis  204  will convey radio-frequency signals over beams that are at greater elevation angles than patch elements  34  located closer to boresight axis  204 . 
     For example, as shown in  FIG.  18   , patch element  34 - 5  may transmit radio-frequency signals  211 . Lens  66  may redirect signals  211  through conical portion  202  and out of hemispherical portion  200  at elevation angle −θ 1 , as shown by arrow (ray)  214 . The magnitude of elevation angle −θ 1  may be greater than 50 degrees, greater than 60 degrees, etc. Signals conveyed in this direction may exhibit sufficient gain (e.g., gain that is not subject to cosine loss) despite being at a relatively high angle with respect to boresight. Patch elements  34  that are located closer to axis  204  than patch element  34 - 5  may transmit radio-frequency signals at lower elevation angles. For example, patch element  34 - 4  may transmit radio-frequency signals through lens  66  that are emitted by lens  66  at elevation angle −θ 2 , as shown by arrow (ray)  212 . Patch element  34 - 3  that is aligned with boresight axis  204  may transmit radio-frequency signals through lens  66  at boresight (e.g., elevation angle θ=0). Similarly, as shown by  FIG.  18   , patch element  34 - 2  may transmit radio-frequency signals through lens  66  in direction  218  (e.g., at elevation angle θ 2 ) and patch element  34 - 1  may transmit radio-frequency signals through lens  66  in direction  220  (e.g., at elevation angle θ 1 ). Patch elements  34  may similarly receive radio-frequency signals from these directions through lens  66 . One or more of patch elements  34  may be activated to transmit radio-frequency in any desired direction(s) using lens  66  (e.g., module  68  may concurrently convey radio-frequency signals in directions  212 ,  214 ,  204 ,  218 , and  220  by activating each of patch elements  34 - 1 ,  34 - 2 ,  34 - 3 ,  34 - 4 , and  34 - 5 ) with satisfactory gain and thus satisfactory wireless link quality. 
     Communication terminal  10  may be subject to industry or regulatory standards limiting the generation of signal beam side-lobes by radiators  30 . Lenses  66  may provide antenna modules  68  with antenna patterns that exhibit relatively low side-lobe gain that are further reduced relative to the main signal beam as the lenses are arrayed, thereby satisfying these industry and regulatory requirements.  FIG.  19    is a side view illustrating a beam of signals that may be conveyed through lens  66 . 
     As shown in  FIG.  19   , curve  226  plots the radiation pattern of a given patch element such as patch element  34 - 5  of  FIG.  18    that has been redirected by lens  66 . As shown by curve  226  of  FIG.  19   , pattern  226  exhibits a peak gain in a particular direction (e.g., a pointing direction  214  as shown in  FIG.  18   ). The geometry of lens  66  may reduce or minimize generation of side-lobes in pattern  226  (e.g., to the order of −13 dB to −20 dB). Dashed curve  224  illustrates the radiation pattern of a radiator with unsatisfactory side-lobe performance. As shown in FIG.  19 , pattern  224  exhibits relatively high gain side-lobes  225 , which may fail to meet industry or regulatory standards on side-lobe performance even as the modules are arrayed. High-gain side-lobes such as side-lobes  225  are not present in pattern  226  associated with module  68 . 
     Summing signals across modules  68  (e.g., as described in connection with  FIGS.  10  and  11   ) may also be performed without generating excessive side-lobes in the radiation pattern of array  70 . For example, phasing each individual module  68  may coherently sum the main signal beam from each module (e.g., in the direction of peak gain), whereas the side lobes of the beams generally remain out of phase. This may prevent coherent summing of the side lobes between modules (lenses). Varying the position of the patch elements in each module may also allow for angular spreading of the side lobes for the different active radiators across the modules such that the side lobes are not coherently summed at the array level, regardless of frequency. 
     In one suitable arrangement, lenses  66  are formed from solid dielectric material. However, as the number of modules  68  in array  70  increases, the number of lenses  66  in array  70  also increases. For example, array  70  may include as many as sixteen modules  68  and thus sixteen lenses  66 , twenty-five modules  68  and lenses  66 , thirty six modules  68  and lenses  66  (e.g., as shown in  FIG.  17   ), forty-nine modules  68  and lenses  66 , or more than forty-nine modules  68  and lenses  66 . If care is not taken, the cumulative mass of lenses  66  across array  70  may become excessive and burdensome. Communication terminal  10  may be especially sensitive to mass (weight) in scenarios where communication terminal  10  is used to form space-based (satellite-based) communication terminals  10 A or  10 B of  FIG.  1   . 
     In order to reduce the mass of lenses  66  and thus array  70  without sacrificing radio-frequency performance, lenses  66  may be formed using a lattice of dielectric material instead of using a single solid dielectric material.  FIG.  20    is a side-view showing how lens  66  may be formed using a lattice of dielectric material. 
     As shown in  FIG.  20   , lens  66  may include multiple layers  228  of dielectric material such as plastic. Each layer  228  may include dielectric segments separated by gaps (e.g., air gaps) that are free from dielectric material or that are filled with a lighter (less dense) dielectric material. Each layer  228  may have the same height H (e.g., 1-3 mm, 2 mm, 0.5-5.0 mm, etc.) or different layers  228  may have different heights. Layers  228  may include a first set of layers  228 A that are interleaved (alternating) with a second set of layers  228 B. Layers  228 A may each have dielectric segments extending in a first direction (e.g., dielectric members having longitudinal axes parallel to the X-axis). Layers  228 B may each have dielectric segments extending in a second direction orthogonal to the first direction (e.g., dielectric members having longitudinal axes parallel to the Y-axis). In this way, dielectric material and thus mass may be removed from lens  66  while still allowing lens  66  to maintain structural integrity. If desired, dielectric cap  216  may be provided over lens  66 . Dielectric cap  216  may be less dense than the dielectric segments in layers  228 A and  228 B. The material of dielectric cap  216  may fill the gaps between the dielectric segments in layers  228 A and  228 B if desired. Dielectric cap  216  may serve as an impedance matching interface between lens  66  and free space and to adjust the average dielectric constant of lens  66 . 
       FIG.  21    is a perspective view of lens  66  having layers  228 A and  228 B of  FIG.  20   . In the example of  FIG.  21   , lens  66  is shown as having a cylindrical base. This is merely illustrative and, if desired, lens  66  may have a base with a conical shape such as conical lens portion  202  of  FIG.  20   . As shown in  FIG.  21   , each layer  228 B may include multiple dielectric segments  240  having longitudinal axes extending parallel to the Y axis. Each segment  240  may be separated from other segments  240  in the same layer by gaps  236 . Similarly, each layer  228 A may include multiple dielectric segments  238  having longitudinal axes extending parallel to the X axis. Each segment  238  may be separated from other segments  238  in the same layer by gaps  234 . Gaps  234  and  236  may sometimes be referred to as horizontal gaps (e.g., because the gaps horizontally or laterally separate the dielectric segments). 
     Each layer  228 A may include any desired number of segments  238  and any desired number of gaps  234 . Each layer  228 B may include any desired number of segments  240  and any desired number of gaps  236 . The number of segments and gaps in each layer may be selected to provide lens  66  with a desired geometric shape, for example. Gaps  236  in layers  228 B may each have width  230 . Gaps  234  in layers  228 A may each have width  232 . The fill factor of lens  66  may be defined by the ratio of the cumulative volume of all of the segments  238  and  240  in lens  66  to the cumulative volume of all of the gaps  236  and  234  in lens  66 . The fill factor may determine the average or effective dielectric constant of lens  66 . Width  230  of gaps  236 , width  232  of gaps  234 , the width of segments  240 , and the width of segments  238  may be selected to provide lens  66  with a desired fill factor and thus a desired average (bulk) dielectric constant (e.g., a bulk dielectric constant that configures lens  66  to direct radio-frequency signals for the corresponding module  68  in desired directions as shown in  FIG.  18   ). As an example, if the dielectric material in segments  240  and  238  of  FIG.  21    has a dielectric constant of 4.0 and gaps  236  and  234  fill half of the total volume of lens  66  with empty space, lens  66  may exhibit a bulk dielectric constant of 2.0. Gaps  236  and/or gaps  234  may be filled with dielectric material to help provide lens  66  with a desired bulk dielectric constant. 
     A greater number and width of gaps  236  and  234  in lens  66  may reduce the mass of lens  66  (and thus the entire array  70 ) relative to scenarios where fewer or narrower gaps are used. However, if width  232  and  230  are excessive, gaps  234  and  236  may undesirably affect (e.g., impede or reflect) the radio-frequency signals conveyed by lens  66 . In order to balance weight savings with radio-frequency performance, width  230  of gaps  236  and width  232  of gaps  234  may each be less than one-tenth of the wavelength of operation for antenna module  68  (or the lowest wavelength of operation in scenarios where module  68  covers multiple frequency bands). In another suitable arrangement, the widths and gaps may each be less than one-fifth, one-sixth, one-seventh, one-eighth, one-ninth, one-eleventh, one-fourth, or one-twelfth of the wavelength of operation for the lowest wavelength of operation of the antenna modules. Similarly, the widths of segments  238  and  240  (and height H of  FIG.  20   ) may also be less than one-tenth or one-sixth of the wavelength of operation for antenna module  68 . This may ensure that segments  240  and  238  and gaps  236  and  234  do not affect the radio-frequency signals propagated through lens  66  (e.g., the interfaces between the dielectric segments and the gaps may be transparent to radio-frequency signals at the wavelength of operation). When configured in this way, each lens  66  may weigh less than scenarios where solid dielectric material is used to form the entirety of lens  66 . For arrays  70  having more than thirty-six modules  68 , providing lenses  66  with the lattice structure shown in  FIGS.  20  and  21    may reduce the total weight of array  70  by 15-20 pounds relative to scenarios where solid lenses are used, as an example. 
     If desired, the layers  228  of lens  66  may be manufactured in pairs, as shown in  FIG.  22   . As shown in  FIG.  22   , each layer  228 A may fabricated from the same piece of dielectric material as an adjacent layer  228 B (e.g., using 3D printing, injection molding, or other manufacturing techniques) to form a pair (doublet) of layers  242 . Different doublets  242  may be vertically stacked on top of each other to form lens  66  of  FIG.  21   . If desired, segments  240  in each layer  228 B and segments  238  in each layer  228 A may include alignment holes  246 . Alignment holes  246  may receive alignment pins  244 , as shown by arrows  248 , that serve to hold each doublet  242  and thus each layer  228  of lens  66  in place. Doublets  242  may be adhered together using adhesive if desired. This example is merely illustrative and, in general, lens  66  may be assembled using any desired assembly methods. 
     The examples of  FIGS.  20  and  21    are merely illustrative. In general, layers  228 A and  288 B may be stacked and/or arranged in other directions (e.g., vertically, diagonally, etc.). Gaps  234  may be considered to laterally (horizontally) separate segments  238  and gaps  236  may be considered to laterally (horizontally) separate segments  240  regardless of the orientation of layers  228 A and  228 B relative to the radiators in the module. Layers  228 A and  228 B need not be formed from the same material and, if desired, different materials may be used to form layers  228 A and  228 B, different layers  228 A may be formed using different materials, different layers  228 B may be formed using different materials, etc. The elongated segments in layers  228 A and  228 B need not follow straight paths and may, if desired, follow meandering paths, curved paths, paths with corners, or other paths. In another suitable arrangement, lens  66  may be formed from a single solid piece of dielectric having holes or gaps formed therein, may be formed from mixtures of different dielectrics having different dielectric constants, may have different regions with different bulk dielectric constants, etc. In scenarios where lens  66  has a varying dielectric constant within its volume, the lens may have a flat shape, cubic shape (e.g., a shape having a flat or planar upper (top) surface rather than a hemispherical top surface), or other shapes while still allowing for the beam directing properties described herein. In another suitable arrangement, substrate  90  may be omitted and the radiators may be attached (e.g., adhered) directly to a bottom surface of the lens, may be formed from waveguide structures pointed towards the lens, etc. 
     The example of  FIGS.  20 - 22    in which lens  66  includes orthogonal dielectric segments across layers  228  is merely illustrative. If desired, lens  66  may be formed from alternating layers of concentric rings and radial spokes. As shown in  FIG.  23   , the lens may include a first set of layers  228 C interleaved with a second set of layers  228 D. A single pair (doublet)  254  of layers  228 C and  228 D is shown in  FIG.  23   . As shown in  FIG.  23   , layer  228 C may include concentric dielectric segments  250  centered around boresight axis  204  (e.g., concentric rings of dielectric material and/or circular segments of dielectric material). Layer  228 D may include dielectric segments  252  arranged in a radial spoke pattern. Dielectric segments  252  may sometimes be referred to herein as radial spokes  252 . Concentric dielectric segments  250  may be separated by lateral gaps  256 . Radial spokes  252  may be separated by lateral gaps  258 . Gaps  256  and  258  may be filled with air or other dielectric material having a dielectric constant different than that of segments  252  and  250 . 
     Radial spokes  252  may include dielectric segments that extend across the entire radius of the lens (e.g., from boresight axis  204  to the peripheral edge of the lens) and/or dielectric segments that extend across only part of the radius of the lens, such as segment  252 ′. Radial spokes  252  may be formed using straight dielectric segments (see, e.g., segment  252 ′) or using dielectric segments that follow meandering paths. Gaps  256  may each have the same width or may have different widths across layer  228 C. Gaps  258  may each have the same width or may have different widths across layer  228 D. Gaps  256 , gaps  258 , the width of segments  250 , and the width and shapes of radial spokes  252  may be selected to provide the lens with a desired fill factor and thus a desired bulk dielectric constant without impacting radio-frequency signals conveyed through the array (e.g., these dimensions may each be less than one-tenth of the wavelength of operation, one-sixth of the wavelength of operation, one-fifth of the wavelength of operation, etc.). Any desired number of radial spokes  252  may be formed in each layer  228 D and any desired number of concentric dielectric segments  250  may be formed in each layer  228 C. These examples are merely illustrative and, in general lens  66  may be formed using any desired dielectric lattice structure. 
     In accordance with some embodiments, a method may be provided as substantially described herein with reference to each or any combination of the Figures contained herein, with reference to each or any techniques disclosed herein, or with reference to each or any combination of Figures and/or techniques disclosed herein. 
     In accordance with some embodiments, a device may be configured to perform any action or combination of actions as substantially described in the disclosures set forth herein. 
     In accordance with some embodiments, a device may include any component or combination of components as described herein and performs any of the functions and/or operations disclosed herein. 
     In accordance with some embodiments, a non-volatile computer-readable medium that may store instructions that, when executed, cause processor electronics to perform any action or combination of actions as substantially described herein. 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20190919
Publication Date: 20230110
Grant Date: 20230110
Priority Date: 20180921
Inventors: Bily, Adam H.
DI NALLO, CARLO
Ettus, Matthew N.
Trela, Michael D.
PAULOTTO, Simone
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q15/02", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q21/06", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/307", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/307", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q21/06", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q15/02", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q25/007", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q19/062", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q15/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/42", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01Q3/34", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/245", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01Q21/061", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q9/0407", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 84810616