PATENT DOCUMENT

Publication Number: US-11700035-B2
Application Number: US-202016920297-A
Country: US
Kind Code: B2

Title: Dielectric resonator antenna modules

Abstract:
An electronic device may be provided with an antenna module having a substrate. A phased antenna array of dielectric resonator antennas and a radio-frequency integrated circuit for the array may be mounted to one or more surfaces of the substrate. The dielectric resonator antennas may include dielectric columns excited by feed probes. The feed probes may be printed onto sidewalls of the dielectric columns or may be pressed against the sidewalls by biasing structures. A plastic substrate may be molded over each dielectric column and each of the feed probes in the array. The feed probes may cover multiple polarizations. The array may include elements for covering multiple frequency bands. The dielectric columns may be aligned a longitudinal axis and may be rotated at a non-zero and non-perpendicular angle with respect to the longitudinal axis.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 a substrate; 
 a phased antenna array having dielectric resonator antennas mounted to a surface of the substrate, wherein one of the dielectric resonator antennas comprises:
 a dielectric resonating element, 
 a feed probe configured to excite a resonant mode of the dielectric resonating element, and 
 a biasing structure that presses the feed probe against the dielectric resonating element, the biasing structure being molded over the feed probe and at least some of the dielectric resonating element. 
 
 
     
     
       2. The electronic device defined in  claim 1 , further comprising:
 a radio-frequency integrated circuit (RFIC) mounted to the substrate, wherein the RFIC is configured to adjust a direction of a signal beam formed by the phased antenna array, the substrate comprises an additional surface opposite the surface, and the RFIC is mounted to the additional surface of the substrate. 
 
     
     
       3. The electronic device defined in  claim 2 , further comprising:
 a board-to-board connector mounted to the surface of the substrate; and 
 radio-frequency transceiver circuitry coupled to the RFIC via the board-to-board connector. 
 
     
     
       4. The electronic device defined in  claim 2 , further comprising:
 an over-mold structure on the additional surface, wherein the RFIC is embedded within the over-mold structure. 
 
     
     
       5. The electronic device defined in  claim 2 , wherein the RFIC is soldered to the surface of the substrate. 
     
     
       6. The electronic device defined in  claim 2 , further comprising:
 an additional phased antenna array mounted to the additional surface of the substrate, wherein the additional phased antenna array is configured to convey radio-frequency signals at a frequency greater than 10 GHz within a signal beam, the RFIC being configured to adjust a direction of the signal beam. 
 
     
     
       7. The electronic device defined in  claim 6 , further comprising:
 peripheral conductive housing structures that run around a periphery of the electronic device; 
 a display having a display cover layer mounted to the peripheral conductive housing structures and having a display module configured to emit light through the display cover layer; and 
 a housing wall mounted to the peripheral conductive housing structures opposite the display cover layer, wherein the phased antenna array is configured to convey additional radio-frequency signals within an additional signal beam through the display cover layer and the additional phased antenna array is configured to convey the radio-frequency signals within the signal beam through the housing wall. 
 
     
     
       8. The electronic device defined in  claim 6 , wherein the additional phased antenna array comprises antennas selected from the group consisting of: stacked patch antennas embedded within the substrate and dielectric resonator antennas mounted to the additional surface of the substrate. 
     
     
       9. The electronic device of  claim 1 , wherein the feed probe biasing structure presses the feed probe against a sidewall of the dielectric resonating element. 
     
     
       10. The electronic device of  claim 9 , further comprising:
 a plastic substrate molded over the feed probe biasing structure and at least some of the dielectric resonating element. 
 
     
     
       11. The electronic device of  claim 10 , wherein the dielectric resonator antennas comprise an additional dielectric resonator antenna, the additional dielectric resonator antenna comprising:
 an additional dielectric resonating element mounted to the surface of the substrate; 
 an additional feed probe configured to excite a resonant mode of the additional dielectric resonating element; and 
 an additional feed probe biasing structure that presses the additional feed probe against the additional dielectric resonating element, wherein the additional feed probe biasing structure is molded over the additional feed probe and at least some of the additional dielectric resonating element, and the plastic substrate is molded over the additional feed probe biasing structure and at least some of the additional dielectric resonating element, wherein the substrate comprises a flexible printed circuit substrate. 
 
     
     
       12. The electronic device of  claim 9 , wherein the dielectric resonating element has an additional sidewall oriented perpendicular to a sidewall of the dielectric resonating element contacting the feed probe, the dielectric resonator antenna comprises an additional feed probe coupled to the additional sidewall, the resonant mode is associated with a first linear polarization, the additional feed probe is configured to excite an additional resonant mode of the dielectric resonating element associated with a second linear polarization orthogonal to the first linear polarization, the feed probe biasing structure presses the additional feed probe against the additional sidewall, and the feed probe biasing structure is molded over the additional feed probe. 
     
     
       13. An electronic device comprising:
 a substrate; 
 a phased antenna array having dielectric resonator antennas mounted to a surface of the substrate, wherein the dielectric resonator antennas are aligned along a longitudinal axis, comprise dielectric resonating elements having sidewalls that are oriented at a non-zero and non-perpendicular angle with respect to the longitudinal axis, and are fed by feed probes coupled to the sidewalls at the surface of the substrate; and 
 feed probe biasing structures molded over the feed probes and configured to hold the feed probes against the sidewalls. 
 
     
     
       14. The electronic device defined in  claim 13 , further comprising:
 a dielectric substrate molded over each of the feed probe biasing structures; and 
 openings in the dielectric substrate, wherein each of the openings is laterally interposed between a respective pair of dielectric resonating elements in the probe-fed dielectric resonator antennas, and wherein each of the dielectric resonating elements comprises first, second, third, and fourth sidewalls, a first feed probe pressed against the first sidewall by a respective one of the feed probe biasing structures, a second feed probe pressed against the second sidewall by the respective one of the feed probe biasing structures, a first parasitic element pressed against the third sidewall by the respective one of the feed probe biasing structures, and a second parasitic element pressed against the fourth sidewall by the respective one of the feed probe biasing structures. 
 
     
     
       15. The electronic device of  claim 13 , further comprising a radio-frequency integrated circuit mounted to the substrate and configured to control the phased antenna array to form a signal beam in a first direction at a first time and configured to control the phased antenna array to form the signal beam in a second direction different from the first direction at a second time.

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with wireless circuitry. 
     Electronic devices often include wireless circuitry. For example, cellular telephones, computers, and other devices often contain antennas and wireless transceivers for supporting wireless communications. 
     It may be desirable to support wireless communications in millimeter wave and centimeter wave communications bands. Millimeter wave communications, which are sometimes referred to as extremely high frequency (EHF) communications, and centimeter wave communications involve communications at frequencies of about 10-300 GHz. Operation at these frequencies may support high bandwidths but may raise significant challenges. For example, radio-frequency communications in millimeter and centimeter wave communications bands can be characterized by substantial attenuation and/or distortion during signal propagation through various mediums. The presence of conductive electronic device components can also make it difficult to incorporate circuitry for handling millimeter and centimeter wave communications into the electronic device. In addition, if care is not taken, manufacturing variations can undesirably limit the mechanical reliability and wireless performance of the antennas in the electronic device. 
     It would therefore be desirable to be able to provide electronic devices with improved components for supporting millimeter and centimeter wave communications. 
     SUMMARY 
     An electronic device may be provided with a housing, a display, and wireless circuitry. The housing may include peripheral conductive housing structures that run around a periphery of the device. The display may include a display cover layer mounted to the peripheral conductive housing structures. The wireless circuitry may include a phased antenna array that conveys radio-frequency signals in one or more frequency bands between 10 GHz and 300 GHz. The phased antenna array may convey the radio-frequency signals through the display cover layer or other dielectric cover layers in the device. 
     The phased antenna array may include probe-fed dielectric resonator antennas. The phased antenna array and a radio-frequency integrated circuit (RFIC) for the phased antenna array may both be integrated into an antenna module. The antenna module may include an antenna module substrate. The RFIC may be surface-mounted to a first surface of the substrate whereas the probe-fed dielectric resonator antennas are mounted to a second surface of the substrate. Alternatively, the RFIC and probe-fed dielectric resonator antennas may be mounted to the same surface of the substrate. An over-mold structure may be provided over the RFIC. Additional phased antenna arrays may be mounted to the substrate if desired. 
     Each of the probe-fed dielectric resonator antennas may include a dielectric resonating element mounted to a surface of the substrate. One or two feed probes may be coupled to sidewalls of the dielectric resonating element at the surface of the substrate to feed the dielectric resonating element. In one suitable arrangement, the feed probes may be formed from conductive traces that are patterned onto the sidewalls. In this arrangement, each dielectric resonating element may be formed on the antenna module at the same time, thereby minimizing mechanical variations to optimize mechanical and wireless performance of the module. The antenna module may be cut from a substrate used to form multiple antenna modules for multiple devices to minimize manufacturing cost and complexity if desired. 
     In another suitable arrangement, the feed probes may be formed from stamped sheet metal and may be pressed against the sidewalls by feed probe biasing structures that are molded over the feed probes and at least some of the dielectric resonating element. The feed probe biasing structures may also press parasitic elements against the sidewalls if desired. A plastic substrate may be molded over the feed probes and at least some of the dielectric resonating element for each of the antennas in the array to form an antenna package. The antenna package may be surface-mounted to the substrate (e.g., a flexible printed circuit) to form the antenna module. The antenna module may be aligned with a notch in a display module for the device. The dielectric resonating elements may be aligned along a longitudinal axis. If desired, each of the sidewalls of the dielectric resonating elements may be rotated at non-zero and non-perpendicular angles with respect to the longitudinal axis to maximize isolation between the antennas. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an illustrative electronic device in accordance with some embodiments. 
         FIG.  2    is a schematic diagram of illustrative circuitry in an electronic device in accordance with some embodiments. 
         FIG.  3    is a schematic diagram of illustrative wireless circuitry in accordance with some embodiments. 
         FIG.  4    is a diagram of an illustrative phased antenna array that may be adjusted using control circuitry to direct a beam of signals in accordance with some embodiments. 
         FIG.  5    is a cross-sectional side view of an illustrative electronic device having phased antenna arrays for radiating through different sides of the device in accordance with some embodiments. 
         FIG.  6    is a perspective view of an illustrative probe-fed dielectric resonator antenna for covering multiple polarizations in accordance with some embodiments. 
         FIG.  7    is a top-down view of an illustrative probe-fed dielectric resonator antenna having multiple feed probes and floating parasitic patches for mitigating cross-polarization interference in accordance with some embodiments. 
         FIG.  8    is a top-down view of an illustrative probe-fed dielectric resonating antenna having a single feed probe and grounded parasitic patches for mitigating cross-polarization interference in accordance with some embodiments. 
         FIG.  9    is a top-down view of an illustrative antenna module having dielectric resonator antennas in accordance with some embodiments. 
         FIG.  10    is a cross-sectional side view of an illustrative antenna module having dielectric resonator antennas in accordance with some embodiments. 
         FIG.  11    is a perspective view of an illustrative antenna module having dielectric resonator antennas in accordance with some embodiments. 
         FIG.  12    is a top-down view of an illustrative antenna module having dielectric resonator antennas and a radio-frequency integrated circuit mounted to the same side of a substrate in accordance with some embodiments. 
         FIG.  13    is a side view of an illustrative antenna module having dielectric resonator antennas and a radio-frequency integrated circuit mounted to the same side of a substrate in accordance with some embodiments. 
         FIG.  14    is a side view of an illustrative antenna module having dielectric resonator antennas on opposing sides of a substrate in accordance with some embodiments. 
         FIG.  15    is a cross-sectional side view of an illustrative antenna module having patch antennas and dielectric resonator antennas at opposing sides of a substrate in accordance with some embodiments. 
         FIGS.  16  and  17    are diagrams of an illustrative assembly process for an antenna module having dielectric resonator antennas mounted to a substrate in accordance with some embodiments. 
         FIG.  18    is a flow chart of illustrative steps that may be performed in assembling an antenna module having dielectric resonator antennas mounted to a substrate in accordance with some embodiments. 
         FIG.  19    is a perspective view of an illustrative antenna module having dielectric resonator antennas with feed probes that are biased towards dielectric resonating elements by biasing structures in accordance with some embodiments. 
         FIG.  20    is a diagram showing how an illustrative antenna module of the type shown in  FIG.  19    may be assembled in accordance with some embodiments. 
         FIG.  21    is a top-down view of an illustrative electronic device having an antenna module aligned with a notch in a display module in accordance with some embodiments. 
         FIG.  22    is a top-down view of an illustrative antenna module having rotated dielectric resonating elements in accordance with some embodiments. 
         FIG.  23    is a perspective view of an illustrative antenna module having rotated dielectric resonating elements in accordance with some embodiments. 
         FIG.  24    is an exploded perspective view of an illustrative antenna module of the type shown in  FIGS.  22  and  23    in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     An electronic device such as electronic device  10  of  FIG.  1    may contain wireless circuitry. The wireless circuitry may include one or more antennas. The antennas may include phased antenna arrays that are used for performing wireless communications using millimeter and centimeter wave signals. Millimeter wave signals, which are sometimes referred to as extremely high frequency (EHF) signals, propagate at frequencies above about 30 GHz (e.g., at 60 GHz or other frequencies between about 30 GHz and 300 GHz). Centimeter wave signals propagate at frequencies between about 10 GHz and 30 GHz. If desired, device  10  may also contain antennas for handling satellite navigation system signals, cellular telephone signals, local wireless area network signals, near-field communications, light-based wireless communications, or other wireless communications. 
     Electronic device  10  may be a portable electronic device or other suitable electronic device. For example, electronic device  10  may be a laptop computer, a tablet computer, a somewhat smaller device such as a wrist-watch device, pendant device, headphone device, earpiece device, or other wearable or miniature device, a handheld device such as a cellular telephone, a media player, or other small portable device. Device  10  may also be a set-top box, a desktop computer, a display into which a computer or other processing circuitry has been integrated, a display without an integrated computer, a wireless access point, a wireless base station, an electronic device incorporated into a kiosk, building, or vehicle, or other suitable electronic equipment. 
     Device  10  may include a housing such as housing  12 . Housing  12 , which may sometimes be referred to as a case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of these materials. In some situations, parts of housing  12  may be formed from dielectric or other low-conductivity material (e.g., glass, ceramic, plastic, sapphire, etc.). In other situations, housing  12  or at least some of the structures that make up housing  12  may be formed from metal elements. 
     Device  10  may, if desired, have a display such as display  14 . Display  14  may be mounted on the front face of device  10  (e.g., display  14  may form some or all of the front face of the device). Display  14  may be a touch screen that incorporates capacitive touch electrodes or may be insensitive to touch. The rear face of housing  12  (i.e., the face of device  10  opposing the front face of device  10 ) may have a substantially planar housing wall such as rear housing wall  12 R (e.g., a planar housing wall). Rear housing wall  12 R may have slots that pass entirely through the rear housing wall and that therefore separate portions of housing  12  from each other. Rear housing wall  12 R may include conductive portions and/or dielectric portions. If desired, rear housing wall  12 R may include a planar metal layer covered by a thin layer or coating of dielectric such as glass, plastic, sapphire, or ceramic. Housing  12  may also have shallow grooves that do not pass entirely through housing  12 . The slots and grooves may be filled with plastic or other dielectrics. If desired, portions of housing  12  that have been separated from each other (e.g., by a through slot) may be joined by internal conductive structures (e.g., sheet metal or other metal members that bridge the slot). 
     Housing  12  may include peripheral housing structures such as peripheral structures  12 W. Conductive portions of peripheral structures  12 W and conductive portions of rear housing wall  12 R may sometimes be referred to herein collectively as conductive structures of housing  12 . Peripheral structures  12 W may run around the periphery of device  10  and display  14 . In configurations in which device  10  and display  14  have a rectangular shape with four edges, peripheral structures  12 W may be implemented using peripheral housing structures that have a rectangular ring shape with four corresponding edges and that extend from rear housing wall  12 R to the front face of device  10  (as an example). Peripheral structures  12 W or part of peripheral structures  12 W may serve as a bezel for display  14  (e.g., a cosmetic trim that surrounds all four sides of display  14  and/or that helps hold display  14  to device  10 ) if desired. Peripheral structures  12 W may, if desired, form sidewall structures for device  10  (e.g., by forming a metal band with vertical sidewalls, curved sidewalls, etc.). 
     Peripheral structures  12 W may be formed of a conductive material such as metal and may therefore sometimes be referred to as peripheral conductive housing structures, conductive housing structures, peripheral metal structures, peripheral conductive sidewalls, peripheral conductive sidewall structures, conductive housing sidewalls, peripheral conductive housing sidewalls, sidewalls, sidewall structures, or a peripheral conductive housing member (as examples). Peripheral conductive housing structures  12 W may be formed from a metal such as stainless steel, aluminum, or other suitable materials. One, two, or more than two separate structures may be used in forming peripheral conductive housing structures  12 W. 
     It is not necessary for peripheral conductive housing structures  12 W to have a uniform cross-section. For example, the top portion of peripheral conductive housing structures  12 W may, if desired, have an inwardly protruding ledge that helps hold display  14  in place. The bottom portion of peripheral conductive housing structures  12 W may also have an enlarged lip (e.g., in the plane of the rear surface of device  10 ). Peripheral conductive housing structures  12 W may have substantially straight vertical sidewalls, may have sidewalls that are curved, or may have other suitable shapes. In some configurations (e.g., when peripheral conductive housing structures  12 W serve as a bezel for display  14 ), peripheral conductive housing structures  12 W may run around the lip of housing  12  (i.e., peripheral conductive housing structures  12 W may cover only the edge of housing  12  that surrounds display  14  and not the rest of the sidewalls of housing  12 ). 
     Rear housing wall  12 R may lie in a plane that is parallel to display  14 . In configurations for device  10  in which some or all of rear housing wall  12 R is formed from metal, it may be desirable to form parts of peripheral conductive housing structures  12 W as integral portions of the housing structures forming rear housing wall  12 R. For example, rear housing wall  12 R of device  10  may include a planar metal structure and portions of peripheral conductive housing structures  12 W on the sides of housing  12  may be formed as flat or curved vertically extending integral metal portions of the planar metal structure (e.g., housing structures  12 R and  12 W may be formed from a continuous piece of metal in a unibody configuration). Housing structures such as these may, if desired, be machined from a block of metal and/or may include multiple metal pieces that are assembled together to form housing  12 . Rear housing wall  12 R may have one or more, two or more, or three or more portions. Peripheral conductive housing structures  12 W and/or conductive portions of rear housing wall  12 R may form one or more exterior surfaces of device  10  (e.g., surfaces that are visible to a user of device  10 ) and/or may be implemented using internal structures that do not form exterior surfaces of device  10  (e.g., conductive housing structures that are not visible to a user of device  10  such as conductive structures that are covered with layers such as thin cosmetic layers, protective coatings, and/or other coating layers that may include dielectric materials such as glass, ceramic, plastic, or other structures that form the exterior surfaces of device  10  and/or serve to hide peripheral conductive housing structures  12 W and/or conductive portions of rear housing wall  12 R from view of the user). 
     Display  14  may have an array of pixels that form an active area AA that displays images for a user of device  10 . For example, active area AA may include an array of display pixels. The array of pixels may be formed from liquid crystal display (LCD) components, an array of electrophoretic pixels, an array of plasma display pixels, an array of organic light-emitting diode display pixels or other light-emitting diode pixels, an array of electrowetting display pixels, or display pixels based on other display technologies. If desired, active area AA may include touch sensors such as touch sensor capacitive electrodes, force sensors, or other sensors for gathering a user input. 
     Display  14  may have an inactive border region that runs along one or more of the edges of active area AA. Inactive area IA of display  14  may be free of pixels for displaying images and may overlap circuitry and other internal device structures in housing  12 . To block these structures from view by a user of device  10 , the underside of the display cover layer or other layers in display  14  that overlap inactive area IA may be coated with an opaque masking layer in inactive area IA. The opaque masking layer may have any suitable color. Inactive area IA may include a recessed region such as notch  8  that extends into active area AA. Active area AA may, for example, be defined by the lateral area of a display module for display  14  (e.g., a display module that includes pixel circuitry, touch sensor circuitry, etc.). The display module may have a recess or notch in upper region  20  of device  10  that is free from active display circuitry (i.e., that forms notch  8  of inactive area IA). Notch  8  may be a substantially rectangular region that is surrounded (defined) on three sides by active area AA and on a fourth side by peripheral conductive housing structures  12 W. 
     Display  14  may be protected using a display cover layer such as a layer of transparent glass, clear plastic, transparent ceramic, sapphire, or other transparent crystalline material, or other transparent layer(s). The display cover layer may have a planar shape, a convex curved profile, a shape with planar and curved portions, a layout that includes a planar main area surrounded on one or more edges with a portion that is bent out of the plane of the planar main area, or other suitable shapes. The display cover layer may cover the entire front face of device  10 . In another suitable arrangement, the display cover layer may cover substantially all of the front face of device  10  or only a portion of the front face of device  10 . Openings may be formed in the display cover layer. For example, an opening may be formed in the display cover layer to accommodate a button. An opening may also be formed in the display cover layer to accommodate ports such as speaker port  16  in notch  8  or a microphone port. Openings may be formed in housing  12  to form communications ports (e.g., an audio jack port, a digital data port, etc.) and/or audio ports for audio components such as a speaker and/or a microphone if desired. 
     Display  14  may include conductive structures such as an array of capacitive electrodes for a touch sensor, conductive lines for addressing pixels, driver circuits, etc. Housing  12  may include internal conductive structures such as metal frame members and a planar conductive housing member (sometimes referred to as a backplate) that spans the walls of housing  12  (i.e., a substantially rectangular sheet formed from one or more metal parts that is welded or otherwise connected between opposing sides of peripheral conductive housing structures  12 W). The backplate may form an exterior rear surface of device  10  or may be covered by layers such as thin cosmetic layers, protective coatings, and/or other coatings that may include dielectric materials such as glass, ceramic, plastic, or other structures that form the exterior surfaces of device  10  and/or serve to hide the backplate from view of the user. Device  10  may also include conductive structures such as printed circuit boards, components mounted on printed circuit boards, and other internal conductive structures. These conductive structures, which may be used in forming a ground plane in device  10 , may extend under active area AA of display  14 , for example. 
     In regions  22  and  20 , openings may be formed within the conductive structures of device  10  (e.g., between peripheral conductive housing structures  12 W and opposing conductive ground structures such as conductive portions of rear housing wall  12 R, conductive traces on a printed circuit board, conductive electrical components in display  14 , etc.). These openings, which may sometimes be referred to as gaps, may be filled with air, plastic, and/or other dielectrics and may be used in forming slot antenna resonating elements for one or more antennas in device  10 , if desired. 
     Conductive housing structures and other conductive structures in device  10  may serve as a ground plane for the antennas in device  10 . The openings in regions  22  and  20  may serve as slots in open or closed slot antennas, may serve as a central dielectric region that is surrounded by a conductive path of materials in a loop antenna, may serve as a space that separates an antenna resonating element such as a strip antenna resonating element or an inverted-F antenna resonating element from the ground plane, may contribute to the performance of a parasitic antenna resonating element, or may otherwise serve as part of antenna structures formed in regions  22  and  20 . If desired, the ground plane that is under active area AA of display  14  and/or other metal structures in device  10  may have portions that extend into parts of the ends of device  10  (e.g., the ground may extend towards the dielectric-filled openings in regions  22  and  20 ), thereby narrowing the slots in regions  22  and  20 . 
     In general, device  10  may include any suitable number of antennas (e.g., one or more, two or more, three or more, four or more, etc.). The antennas in device  10  may be located at opposing first and second ends of an elongated device housing (e.g., ends at regions  22  and  20  of device  10  of  FIG.  1   ), along one or more edges of a device housing, in the center of a device housing, in other suitable locations, or in one or more of these locations. The arrangement of  FIG.  1    is merely illustrative. 
     Portions of peripheral conductive housing structures  12 W may be provided with peripheral gap structures. For example, peripheral conductive housing structures  12 W may be provided with one or more gaps such as gaps  18 , as shown in  FIG.  1   . The gaps in peripheral conductive housing structures  12 W may be filled with dielectric such as polymer, ceramic, glass, air, other dielectric materials, or combinations of these materials. Gaps  18  may divide peripheral conductive housing structures  12 W into one or more peripheral conductive segments. The conductive segments that are formed in this way may form parts of antennas in device  10  if desired. Gaps  18  may be omitted if desired. Other dielectric openings may be formed in peripheral conductive housing structures  12 W (e.g., dielectric openings other than gaps  18 ) and may serve as dielectric antenna windows for antennas mounted within the interior of device  10 . Antennas within device  10  may be aligned with the dielectric antenna windows for conveying radio-frequency signals through peripheral conductive housing structures  12 W. Antennas within device  10  may also be aligned with inactive area IA of display  14  for conveying radio-frequency signals through display  14 . 
     In order to provide an end user of device  10  with as large of a display as possible (e.g., to maximize an area of the device used for displaying media, running applications, etc.), it may be desirable to increase the amount of area at the front face of device  10  that is covered by active area AA of display  14 . Increasing the size of active area AA may reduce the size of inactive area IA within device  10 . This may reduce the area behind display  14  that is available for antennas within device  10 . For example, active area AA of display  14  may include conductive structures that serve to block radio-frequency signals handled by antennas mounted behind active area AA from radiating through the front face of device  10 . It would therefore be desirable to be able to provide antennas that occupy a small amount of space within device  10  (e.g., to allow for as large of a display active area AA as possible) while still allowing the antennas to communicate with wireless equipment external to device  10  with satisfactory efficiency bandwidth. 
     In a typical scenario, device  10  may have one or more upper antennas and one or more lower antennas (as an example). An upper antenna may, for example, be formed at the upper end of device  10  in region  20 . A lower antenna may, for example, be formed at the lower end of device  10  in region  22 . Additional antennas may be formed along the edges of housing  12  extending between regions  20  and  22  if desired. The antennas may be used separately to cover identical communications bands, overlapping communications bands, or separate communications bands. The antennas may be used to implement an antenna diversity scheme or a multiple-input-multiple-output (MIMO) antenna scheme. Other antennas for covering any other desired frequencies may also be mounted at any desired locations within the interior of device  10 . The example of  FIG.  1    is merely illustrative. If desired, housing  12  may have other shapes (e.g., a square shape, cylindrical shape, spherical shape, combinations of these and/or different shapes, etc.). 
     A schematic diagram of illustrative components that may be used in device  10  is shown in  FIG.  2   . As shown in  FIG.  2   , device  10  may include control circuitry  28 . Control circuitry  28  may include storage such as storage circuitry  30 . Storage circuitry  30  may include hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid-state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Control circuitry  28  may include processing circuitry such as processing circuitry  32 . Processing circuitry  32  may be used to control the operation of device  10 . Processing circuitry  32  may include on one or more microprocessors, microcontrollers, digital signal processors, host processors, baseband processor integrated circuits, application specific integrated circuits, central processing units (CPUs), etc. Control circuitry  28  may be configured to perform operations in device  10  using hardware (e.g., dedicated hardware or circuitry), firmware, and/or software. Software code for performing operations in device  10  may be stored on storage circuitry  30  (e.g., storage circuitry  30  may include non-transitory (tangible) computer readable storage media that stores the software code). The software code may sometimes be referred to as program instructions, software, data, instructions, or code. Software code stored on storage circuitry  30  may be executed by processing circuitry  32 . 
     Control circuitry  28  may be used to run software on device  10  such as internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, etc. To support interactions with external equipment, control circuitry  28  may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry  28  include 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 WPAN protocols, IEEE 802.11ad protocols, cellular telephone protocols, MIMO protocols, antenna diversity protocols, satellite navigation system protocols, antenna-based spatial ranging protocols (e.g., radio detection and ranging (RADAR) protocols or other desired range detection protocols for signals conveyed at millimeter and centimeter wave frequencies), etc. Each communication protocol may be associated with a corresponding radio access technology (RAT) that specifies the physical connection methodology used in implementing the protocol. 
     Device  10  may include input-output circuitry  24 . Input-output circuitry  24  may include input-output devices  26 . Input-output devices  26  may be used to allow data to be supplied to device  10  and to allow data to be provided from device  10  to external devices. Input-output devices  26  may include user interface devices, data port devices, sensors, and other input-output components. For example, input-output devices may include touch screens, displays without touch sensor capabilities, buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, speakers, status indicators, light sources, audio jacks and other audio port components, digital data port devices, light sensors, gyroscopes, accelerometers or other components that can detect motion and device orientation relative to the Earth, capacitance sensors, proximity sensors (e.g., a capacitive proximity sensor and/or an infrared proximity sensor), magnetic sensors, and other sensors and input-output components. 
     Input-output circuitry  24  may include wireless circuitry such as wireless circuitry  34  for wirelessly conveying radio-frequency signals. While control circuitry  28  is shown separately from wireless circuitry  34  in the example of  FIG.  2    for the sake of clarity, wireless circuitry  34  may include processing circuitry that forms a part of processing circuitry  32  and/or storage circuitry that forms a part of storage circuitry  30  of control circuitry  28  (e.g., portions of control circuitry  28  may be implemented on wireless circuitry  34 ). As an example, control circuitry  28  may include baseband processor circuitry or other control components that form a part of wireless circuitry  34 . 
     Wireless circuitry  34  may include millimeter and centimeter wave transceiver circuitry such as millimeter/centimeter wave transceiver circuitry  38 . Millimeter/centimeter wave transceiver circuitry  38  may support communications at frequencies between about 10 GHz and 300 GHz. For example, millimeter/centimeter wave transceiver circuitry  38  may support communications in Extremely High Frequency (EHF) or millimeter wave communications bands between about 30 GHz and 300 GHz and/or in centimeter wave communications bands between about 10 GHz and 30 GHz (sometimes referred to as Super High Frequency (SHF) bands). As examples, millimeter/centimeter wave transceiver circuitry  38  may support communications in an IEEE K communications band between about 18 GHz and 27 GHz, a K a  communications band between about 26.5 GHz and 40 GHz, a K u  communications band between about 12 GHz and 18 GHz, a V communications band between about 40 GHz and 75 GHz, a W communications band between about 75 GHz and 110 GHz, or any other desired frequency band between approximately 10 GHz and 300 GHz. If desired, millimeter/centimeter wave transceiver circuitry  38  may support IEEE 802.11ad communications at 60 GHz and/or 5 th  generation mobile networks or 5 th  generation wireless systems (5G) communications bands between 27 GHz and 90 GHz. Millimeter/centimeter wave transceiver circuitry  38  may be formed from one or more integrated circuits (e.g., multiple integrated circuits mounted on a common printed circuit in a system-in-package device, one or more integrated circuits mounted on different substrates, etc.). 
     If desired, millimeter/centimeter wave transceiver circuitry  38  (sometimes referred to herein simply as transceiver circuitry  38  or millimeter/centimeter wave circuitry  38 ) may perform spatial ranging operations using radio-frequency signals at millimeter and/or centimeter wave signals that are transmitted and received by millimeter/centimeter wave transceiver circuitry  38 . The received signals may be a version of the transmitted signals that have been reflected off of external objects and back towards device  10 . Control circuitry  28  may process the transmitted and received signals to detect or estimate a range between device  10  and one or more external objects in the surroundings of device  10  (e.g., objects external to device  10  such as the body of a user or other persons, other devices, animals, furniture, walls, or other objects or obstacles in the vicinity of device  10 ). If desired, control circuitry  28  may also process the transmitted and received signals to identify a two or three-dimensional spatial location of the external objects relative to device  10 . 
     Spatial ranging operations performed by millimeter/centimeter wave transceiver circuitry  38  are unidirectional. Millimeter/centimeter wave transceiver circuitry  38  may additionally or alternatively perform bidirectional communications with external wireless equipment. Bidirectional communications involve both the transmission of wireless data by millimeter/centimeter wave transceiver circuitry  38  and the reception of wireless data that has been transmitted by external wireless equipment. The wireless data may, for example, include data that has been encoded into corresponding data packets such as wireless data associated with a telephone call, streaming media content, internet browsing, wireless data associated with software applications running on device  10 , email messages, etc. 
     If desired, wireless circuitry  34  may include transceiver circuitry for handling communications at frequencies below 10 GHz such as non-millimeter/centimeter wave transceiver circuitry  36 . Non-millimeter/centimeter wave transceiver circuitry  36  may include wireless local area network (WLAN) transceiver circuitry that handles 2.4 GHz and 5 GHz bands for Wi-Fi® (IEEE 802.11) communications, wireless personal area network (WPAN) transceiver circuitry that handles the 2.4 GHz Bluetooth® communications band, cellular telephone transceiver circuitry that handles cellular telephone communications bands from 700 to 960 MHz, 1710 to 2170 MHz, 2300 to 2700 MHz, and/or or any other desired cellular telephone communications bands between 600 MHz and 4000 MHz, GPS receiver circuitry that receives GPS signals at 1575 MHz or signals for handling other satellite positioning data (e.g., GLONASS signals at 1609 MHz), television receiver circuitry, AM/FM radio receiver circuitry, paging system transceiver circuitry, ultra-wideband (UWB) transceiver circuitry, near field communications (NFC) circuitry, etc. Non-millimeter/centimeter wave transceiver circuitry  36  and millimeter/centimeter wave transceiver circuitry  38  may each include one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive radio-frequency components, switching circuitry, transmission line structures, and other circuitry for handling radio-frequency signals. Non-millimeter/centimeter wave transceiver circuitry  36  may be omitted if desired. 
     Wireless circuitry  34  may include antennas  40 . Non-millimeter/centimeter wave transceiver circuitry  36  may convey radio-frequency signals below 10 GHz using one or more antennas  40 . Millimeter/centimeter wave transceiver circuitry  38  may convey radio-frequency signals above 10 GHz (e.g., at millimeter wave and/or centimeter wave frequencies) using antennas  40 . In general, transceiver circuitry  36  and  38  may be configured to cover (handle) any suitable communications (frequency) bands of interest. The transceiver circuitry may convey radio-frequency signals using antennas  40  (e.g., antennas  40  may convey the radio-frequency signals for the transceiver circuitry). The term “convey radio-frequency signals” as used herein means the transmission and/or reception of the radio-frequency signals (e.g., for performing unidirectional and/or bidirectional wireless communications with external wireless communications equipment). Antennas  40  may transmit the radio-frequency signals by radiating the radio-frequency signals into free space (or to freespace through intervening device structures such as a dielectric cover layer). Antennas  40  may additionally or alternatively receive the radio-frequency signals from free space (e.g., through intervening devices structures such as a dielectric cover layer). The transmission and reception of radio-frequency signals by antennas  40  each involve the excitation or resonance of antenna currents on an antenna resonating element in the antenna by the radio-frequency signals within the frequency band(s) of operation of the antenna. 
     In satellite navigation system links, cellular telephone links, and other long-range links, radio-frequency signals are typically used to convey data over thousands of feet or miles. In Wi-Fi® and Bluetooth® links at 2.4 and 5 GHz and other short-range wireless links, radio-frequency signals are typically used to convey data over tens or hundreds of feet. Millimeter/centimeter wave transceiver circuitry  38  may convey radio-frequency signals over short distances that travel over a line-of-sight path. To enhance signal reception for millimeter and centimeter wave communications, phased antenna arrays and beam steering techniques may be used (e.g., schemes in which antenna signal phase and/or magnitude for each antenna in an array are adjusted to perform beam steering). Antenna diversity schemes may also be used to ensure that the antennas that have become blocked or that are otherwise degraded due to the operating environment of device  10  can be switched out of use and higher-performing antennas used in their place. 
     Antennas  40  in wireless circuitry  34  may be formed using any suitable antenna types. For example, antennas  40  may include antennas with resonating elements that are formed from stacked patch antenna structures, loop antenna structures, patch antenna structures, inverted-F antenna structures, slot antenna structures, planar inverted-F antenna structures, monopole antenna structures, dipole antenna structures, helical antenna structures, Yagi (Yagi-Uda) antenna structures, hybrids of these designs, etc. In another suitable arrangement, antennas  40  may include antennas with dielectric resonating elements such as dielectric resonator antennas. If desired, one or more of antennas  40  may be cavity-backed antennas. Different types of antennas may be used for different bands and combinations of bands. For example, one type of antenna may be used in forming a non-millimeter/centimeter wave wireless link for non-millimeter/centimeter wave transceiver circuitry  36  and another type of antenna may be used in conveying radio-frequency signals at millimeter and/or centimeter wave frequencies for millimeter/centimeter wave transceiver circuitry  38 . Antennas  40  that are used to convey radio-frequency signals at millimeter and centimeter wave frequencies may be arranged in one or more phased antenna arrays. 
     A schematic diagram of an antenna  40  that may be formed in a phased antenna array for conveying radio-frequency signals at millimeter and centimeter wave frequencies is shown in  FIG.  3   . As shown in  FIG.  3   , antenna  40  may be coupled to millimeter/centimeter (MM/CM) wave transceiver circuitry  38 . Millimeter/centimeter wave transceiver circuitry  38  may be coupled to antenna feed  44  of antenna  40  using a transmission line path that includes radio-frequency transmission line  42 . Radio-frequency transmission line  42  may include a positive signal conductor such as signal conductor  46  and may include a ground conductor such as ground conductor  48 . Ground conductor  48  may be coupled to the antenna ground for antenna  40  (e.g., over a ground antenna feed terminal of antenna feed  44  located at the antenna ground). Signal conductor  46  may be coupled to the antenna resonating element for antenna  40 . For example, signal conductor  46  may be coupled to a positive antenna feed terminal of antenna feed  44  located at the antenna resonating element. 
     In another suitable arrangement, antenna  40  may be a probe-fed antenna that is fed using a feed probe. In this arrangement, antenna feed  44  may be implemented as a feed probe. Signal conductor  46  may be coupled to the feed probe. Radio-frequency transmission line  42  may convey radio-frequency signals to and from the feed probe. When radio-frequency signals are being transmitted over the feed probe and the antenna, the feed probe may excite the resonating element for the antenna (e.g., may excite electromagnetic resonant modes of a dielectric antenna resonating element for antenna  40 ). The resonating element may radiate the radio-frequency signals in response to excitation by the feed probe. Similarly, when radio-frequency signals are received by the antenna (e.g., from free space), the radio-frequency signals may excite the resonating element for the antenna (e.g., may excite electromagnetic resonant modes of the dielectric antenna resonating element for antenna  40 ). This may produce antenna currents on the feed probe and the corresponding radio-frequency signals may be passed to the transceiver circuitry over the radio-frequency transmission line. 
     Radio-frequency transmission line  42  may include a stripline transmission line (sometimes referred to herein simply as a stripline), a coaxial cable, a coaxial probe realized by metalized vias, a microstrip transmission line, an edge-coupled microstrip transmission line, an edge-coupled stripline transmission lines, a waveguide structure, combinations of these, etc. Multiple types of transmission lines may be used to form the transmission line path that couples millimeter/centimeter wave transceiver circuitry  38  to antenna feed  44 . Filter circuitry, switching circuitry, impedance matching circuitry, phase shifter circuitry, amplifier circuitry, and/or other circuitry may be interposed on radio-frequency transmission line  42 , if desired. 
     Radio-frequency transmission lines in device  10  may be integrated into ceramic substrates, rigid printed circuit boards, and/or flexible printed circuits. In one suitable arrangement, radio-frequency transmission lines in device  10  may be integrated within multilayer laminated structures (e.g., layers of a conductive material such as copper and a dielectric material such as a resin that are laminated together without intervening adhesive) that may be folded or bent in multiple dimensions (e.g., two or three dimensions) and that maintain a bent or folded shape after bending (e.g., the multilayer laminated structures may be folded into a particular three-dimensional shape to route around other device components and may be rigid enough to hold its shape after folding without being held in place by stiffeners or other structures). All of the multiple layers of the laminated structures may be batch laminated together (e.g., in a single pressing process) without adhesive (e.g., as opposed to performing multiple pressing processes to laminate multiple layers together with adhesive). 
       FIG.  4    shows how antennas  40  for handling radio-frequency signals at millimeter and centimeter wave frequencies may be formed in a phased antenna array. As shown in  FIG.  4   , phased antenna array  54  (sometimes referred to herein as array  54 , antenna array  54 , or array  54  of antennas  40 ) may be coupled to radio-frequency transmission lines  42 . For example, a first antenna  40 - 1  in phased antenna array  54  may be coupled to a first radio-frequency transmission line  42 - 1 , a second antenna  40 - 2  in phased antenna array  54  may be coupled to a second radio-frequency transmission line  42 - 2 , an Nth antenna  40 -N in phased antenna array  54  may be coupled to an Nth radio-frequency transmission line  42 -N, etc. While antennas  40  are described herein as forming a phased antenna array, the antennas  40  in phased antenna array  54  may sometimes also be referred to as collectively forming a single phased array antenna. 
     Antennas  40  in phased antenna array  54  may be arranged in any desired number of rows and columns or in any other desired pattern (e.g., the antennas need not be arranged in a grid pattern having rows and columns). During signal transmission operations, radio-frequency transmission lines  42  may be used to supply signals (e.g., radio-frequency signals such as millimeter wave and/or centimeter wave signals) from millimeter/centimeter wave transceiver circuitry  38  ( FIG.  3   ) to phased antenna array  54  for wireless transmission. During signal reception operations, radio-frequency transmission lines  42  may be used to supply signals received at phased antenna array  54  (e.g., from external wireless equipment or transmitted signals that have been reflected off of external objects) to millimeter/centimeter wave transceiver circuitry  38  ( FIG.  3   ). 
     The use of multiple antennas  40  in phased antenna array  54  allows beam steering arrangements to be implemented by controlling the relative phases and magnitudes (amplitudes) of the radio-frequency signals conveyed by the antennas. In the example of  FIG.  4   , antennas  40  each have a corresponding radio-frequency phase and magnitude controller  50  (e.g., a first phase and magnitude controller  50 - 1  interposed on radio-frequency transmission line  42 - 1  may control phase and magnitude for radio-frequency signals handled by antenna  40 - 1 , a second phase and magnitude controller  50 - 2  interposed on radio-frequency transmission line  42 - 2  may control phase and magnitude for radio-frequency signals handled by antenna  40 - 2 , an Nth phase and magnitude controller  50 -N interposed on radio-frequency transmission line  42 -N may control phase and magnitude for radio-frequency signals handled by antenna  40 -N, etc.). 
     Phase and magnitude controllers  50  may each include circuitry for adjusting the phase of the radio-frequency signals on radio-frequency transmission lines  42  (e.g., phase shifter circuits) and/or circuitry for adjusting the magnitude of the radio-frequency signals on radio-frequency transmission lines  42  (e.g., power amplifier and/or low noise amplifier circuits). Phase and magnitude controllers  50  may sometimes be referred to collectively herein as beam steering circuitry (e.g., beam steering circuitry that steers the beam of radio-frequency signals transmitted and/or received by phased antenna array  54 ). 
     Phase and magnitude controllers  50  may adjust the relative phases and/or magnitudes of the transmitted signals that are provided to each of the antennas in phased antenna array  54  and may adjust the relative phases and/or magnitudes of the received signals that are received by phased antenna array  54 . Phase and magnitude controllers  50  may, if desired, include phase detection circuitry for detecting the phases of the received signals that are received by phased antenna array  54 . The term “beam” or “signal beam” may be used herein to collectively refer to wireless signals that are transmitted and received by phased antenna array  54  in a particular direction. The signal beam may exhibit a peak gain that is oriented in a particular pointing direction at a corresponding pointing angle (e.g., based on constructive and destructive interference from the combination of signals from each antenna in the phased antenna array). The term “transmit beam” may sometimes be used herein to refer to radio-frequency signals that are transmitted in a particular direction whereas the term “receive beam” may sometimes be used herein to refer to radio-frequency signals that are received from a particular direction. 
     If, for example, phase and magnitude controllers  50  are adjusted to produce a first set of phases and/or magnitudes for transmitted radio-frequency signals, the transmitted signals will form a transmit beam as shown by beam B 1  of  FIG.  4    that is oriented in the direction of point A. If, however, phase and magnitude controllers  50  are adjusted to produce a second set of phases and/or magnitudes for the transmitted signals, the transmitted signals will form a transmit beam as shown by beam B 2  that is oriented in the direction of point B. Similarly, if phase and magnitude controllers  50  are adjusted to produce the first set of phases and/or magnitudes, radio-frequency signals (e.g., radio-frequency signals in a receive beam) may be received from the direction of point A, as shown by beam B 1 . If phase and magnitude controllers  50  are adjusted to produce the second set of phases and/or magnitudes, radio-frequency signals may be received from the direction of point B, as shown by beam B 2 . 
     Each phase and magnitude controller  50  may be controlled to produce a desired phase and/or magnitude based on a corresponding control signal  52  received from control circuitry  28  of  FIG.  2    (e.g., the phase and/or magnitude provided by phase and magnitude controller  50 - 1  may be controlled using control signal  52 - 1 , the phase and/or magnitude provided by phase and magnitude controller  50 - 2  may be controlled using control signal  52 - 2 , etc.). If desired, the control circuitry may actively adjust control signals  52  in real time to steer the transmit or receive beam in different desired directions over time. Phase and magnitude controllers  50  may provide information identifying the phase of received signals to control circuitry  28  if desired. A codebook on device  10  may map each beam pointing angle to a corresponding set of phase and magnitude values to be provided to phase and magnitude controllers  50  (e.g., the control circuitry may generate control signals  52  based on information from the codebook). 
     When performing wireless communications using radio-frequency signals at millimeter and centimeter wave frequencies, the radio-frequency signals are conveyed over a line of sight path between phased antenna array  54  and external communications equipment. If the external object is located at point A of  FIG.  4   , phase and magnitude controllers  50  may be adjusted to steer the signal beam towards point A (e.g., to steer the pointing direction of the signal beam towards point A). Phased antenna array  54  may transmit and receive radio-frequency signals in the direction of point A. Similarly, if the external communications equipment is located at point B, phase and magnitude controllers  50  may be adjusted to steer the signal beam towards point B (e.g., to steer the pointing direction of the signal beam towards point B). Phased antenna array  54  may transmit and receive radio-frequency signals in the direction of point B. In the example of  FIG.  4   , beam steering is shown as being performed over a single degree of freedom for the sake of simplicity (e.g., towards the left and right on the page of  FIG.  4   ). However, in practice, the beam may be steered over two or more degrees of freedom (e.g., in three dimensions, into and out of the page and to the left and right on the page of  FIG.  4   ). Phased antenna array  54  may have a corresponding field of view over which beam steering can be performed (e.g., in a hemisphere or a segment of a hemisphere over the phased antenna array). If desired, device  10  may include multiple phased antenna arrays that each face a different direction to provide coverage from multiple sides of the device. 
       FIG.  5    is a cross-sectional side view of device  10  in an example where device  10  has multiple phased antenna arrays. As shown in  FIG.  5   , peripheral conductive housing structures  12 W may extend around the (lateral) periphery of device  10  and may extend from rear housing wall  12 R to display  14 . Display  14  may have a display module such as display module  64  (sometimes referred to as a display panel or conductive display structures). Display module  64  may include pixel circuitry, touch sensor circuitry, force sensor circuitry, and/or any other desired circuitry for forming active area AA of display  14 . Display  14  may include a dielectric cover layer such as display cover layer  56  that overlaps display module  64 . Display module  64  may emit image light and may receive sensor input through display cover layer  56 . Display cover layer  56  and display  14  may be mounted to peripheral conductive housing structures  12 W. The lateral area of display  14  that does not overlap display module  64  may form inactive area IA of display  14 . 
     Device  10  may include multiple phased antenna arrays (e.g., phased antenna arrays  54  of  FIG.  4   ). For example, device  10  may include a rear-facing phased antenna array. The rear-facing phased antenna array may be adhered to rear housing wall  12 R using adhesive, may be pressed against (e.g., in contact with) rear housing wall  12 R, or may be spaced apart from rear housing wall  12 R. The rear-facing phased antenna array may transmit and/or receive radio-frequency signals  60  at millimeter and centimeter wave frequencies through rear housing wall  12 R. In scenarios where rear housing wall  12 R includes metal portions, radio-frequency signals  60  may be conveyed through an aperture or opening in the metal portions of rear housing wall  12 R or may be conveyed through other dielectric portions of rear housing wall  12 R. The aperture may be overlapped by a dielectric cover layer or dielectric coating that extends across the lateral area of rear housing wall  12 R (e.g., between peripheral conductive housing structures  12 W). The rear-facing phased antenna array may perform beam steering for radio-frequency signals  60  across at least some of the hemisphere below the rear face of device  10 . 
     The field of view of the rear-facing phased antenna array is limited to the hemisphere under the rear face of device  10 . Display module  64  and other components  58  (e.g., portions of input-output circuitry  24  or control circuitry  28  of  FIG.  2   , a battery for device  10 , etc.) in device  10  include conductive structures. If care is not taken, these conductive structures may block radio-frequency signals from being conveyed by a phased antenna array within device  10  across the hemisphere over the front face of device  10 . While a front-facing phased antenna array for covering the hemisphere over the front face of device  10  may be mounted against display cover layer  56  within inactive area IA, there may be insufficient space between the lateral periphery of display module  64  and peripheral conductive housing structures  12 W to form all of the circuitry and radio-frequency transmission lines necessary to fully support the phased antenna array, particularly as the size of active area AA is maximized. 
     In order to mitigate these issues and provide coverage through the front face of device  10 , a front-facing phased antenna array may be mounted within peripheral region  66  of device  10 . The antennas in the front-facing phased antenna array may include dielectric resonator antennas. Dielectric resonator antennas may occupy less area in the X-Y plane of  FIG.  5    than other types of antennas such as patch antennas and slot antennas. Implementing the antennas as dielectric resonator antennas may allow the radiating elements of the front-facing phased antenna array to fit within inactive area IA between display module  64  and peripheral conductive housing structures  12 W. At the same time, the radio-frequency transmission lines and other components for the phased antenna array may be located behind (under) display module  64 . The front-facing phased antenna array may transmit and/or receive radio-frequency signals  62  at millimeter and centimeter wave frequencies through display cover layer  56 . The front-facing phased antenna array may perform beam steering for radio-frequency signals  62  across at least some of the hemisphere above the front face of device  10 . 
     Device  10  may include both a front-facing phased antenna array (e.g., within peripheral region  66 ) and a rear-facing phased antenna array (e.g., within peripheral region  66  or elsewhere between display module  64  and rear housing wall  12 R). If desired, device  10  may additionally or alternatively include one or more side-facing phased antenna arrays. The side-facing phased antenna arrays may be aligned with dielectric antenna windows in peripheral conductive housing structures  12 W. The front, rear, and/or side-facing phased antenna arrays may be omitted if desired. The front and rear-facing phased antenna arrays (and optionally the side-facing phased antenna arrays) may collectively provide radio-frequency cover across an entire sphere around device  10 . 
     The phased antenna array(s)  54  in device  10  may be formed in corresponding integrated antenna modules. Each antenna module may include a substrate such as a rigid printed circuit board substrate, a flexible printed circuit substrate, a plastic substrate, or a ceramic substrate, and one or more phased antenna arrays mounted to the substrate. Each antenna module may also include electronic components (e.g., radio-frequency components) that support the operations of the phased antenna array(s) therein. For example, each antenna module may include a radio-frequency integrated circuit (e.g., an integrated circuit chip) or other circuitry mounted to the corresponding substrate. Transmission line structures (e.g., radio-frequency signal traces), conductive vias, conductive traces, solder balls, or other conductive interconnect structures may couple the radio-frequency integrated circuit to each of the antennas in the phased antenna array(s) of the antenna module. The radio-frequency integrated circuit (RFIC) and/or other electronic components in the antenna module may include radio-frequency components such as amplifier circuitry, phase shifter circuitry (e.g., phase and magnitude controllers  50  of  FIG.  4   ), and/or other circuitry that operates on radio-frequency signals. The rear-facing, front-facing, and/or side-facing phased antenna array(s) in device  10  may be formed within respective antenna modules. In another suitable arrangement, a rear-facing and front-facing phased antenna array may be formed as a part of the same antenna module in device  10 . 
       FIG.  6    is a perspective view of an illustrative probe-fed dielectric resonator antenna that may be used in forming the antennas of any of the phased antenna arrays in device  10 . Antenna  40  of  FIG.  6    may be a dielectric resonator antenna. In this example, antenna  40  includes a dielectric resonating element  68  mounted to an underlying substrate such as substrate  72 . Substrate  72  may, for example, be the substrate of a corresponding antenna module in device  10 . Substrate  72  may be a rigid printed circuit board substrate, a flexible printed circuit substrate, a ceramic substrate, a plastic substrate, or any other desired substrate. 
     In the example of  FIG.  6   , antenna  40  is a dual-polarization antenna that conveys both vertically and horizontally polarized radio-frequency signals  84  (e.g., linearly-polarized signals having orthogonal electric field orientations). This example is merely illustrative and, in another suitable arrangement, antenna  40  may only cover a single polarization. Antenna  40  may be fed using radio-frequency transmission lines that are formed on and/or embedded within flexible substrate  72  such as radio-frequency transmission lines  88  (e.g., a first radio-frequency transmission line  88 V for conveying vertically-polarized signals and a second radio-frequency transmission line  88 H for conveying horizontally-polarized signals). Radio-frequency transmission lines  88 V and  88 H may, for example, form part of radio-frequency transmission lines  42  of  FIGS.  3  and  4   . Radio-frequency transmission lines  88 V and  88 H may include ground traces (e.g., for forming part of ground conductor  48  of  FIG.  3   ) and signal traces (e.g., for forming part of signal conductor  46  of  FIG.  3   ) on and/or embedded within substrate  72 . Radio-frequency transmission lines  88 V and  88 H may be coupled to a radio-frequency integrated circuit or other radio-frequency components on the antenna module that includes antenna  40 . 
     Dielectric resonating element  68  of antenna  40  may be formed from a column (pillar) of dielectric material mounted to the top surface of substrate  72 . If desired, dielectric resonating element  68  may be embedded within (e.g., laterally surrounded by) a dielectric substrate mounted to the top surface of substrate  72  such as dielectric substrate  70 . Dielectric resonating element  68  may have a height  96  that extends from a bottom surface  82  at substrate  72  to an opposing top surface  80 . Dielectric substrate  70  (sometimes referred to herein as over-mold structure  70 ) may extend across some or all of height  96 . Top surface  80  may lie flush with the top surface of dielectric substrate  70 , may protrude beyond the top surface of dielectric substrate  70 , or dielectric substrate  70  may extend over and cover top surface  80  of dielectric resonating element  68 . 
     The operating (resonant) frequency of antenna  40  may be selected by adjusting the dimensions of dielectric resonating element  68  (e.g., in the direction of the X, Y, and/or Z axes of  FIG.  6   ). Dielectric resonating element  68  may be formed from a column of dielectric material having dielectric constant dk 1 . Dielectric constant dk 1  may be relatively high (e.g., greater than 10.0, greater than 12.0, greater than 15.0, greater than 20.0, between 22.0 and 25.0, between 15.0 and 40.0, between 10.0 and 50.0, between 18.0 and 30.0, between 12.0 and 45.0, etc.). In one suitable arrangement, dielectric resonating element  68  may be formed from zirconia or a ceramic material. Other dielectric materials may be used to form dielectric resonating element  68  if desired. 
     Dielectric substrate  70  may be formed from a material having dielectric constant dk 2 . Dielectric constant dk 2  may be less than dielectric constant dk 1  of dielectric resonating element  68  (e.g., less than 18.0, less than 15.0, less than 10.0, between 3.0 and 4.0, less than 5.0, between 2.0 and 5.0, etc.). Dielectric constant dk 2  may be less than dielectric constant dk 1  by at least 10.0, 5.0, 15.0, 12.0, 6.0, etc. In one suitable arrangement, dielectric substrate  70  may be formed from molded plastic (e.g., injection molded plastic). Other dielectric materials may be used to form dielectric substrate  70  or dielectric substrate  70  may be omitted if desired. The difference in dielectric constant between dielectric resonating element  68  and dielectric substrate  70  may establish a radio-frequency boundary condition between dielectric resonating element  68  and dielectric substrate  70  from bottom surface  82  to top surface  80 . This may configure dielectric resonating element  68  to serve as a resonating waveguide for propagating radio-frequency signals  84  at millimeter and centimeter wave frequencies. 
     Dielectric substrate  70  may have a width (thickness)  94  on some or all sides of dielectric resonating element  68 . Width  94  may be selected to isolate dielectric resonating element  68  from surrounding device structures and/or from other dielectric resonating elements in the same antenna module and to minimize signal reflections in dielectric substrate  70 . Width  94  may be, for example, at least one-tenth of the effective wavelength of the radio-frequency signals in a dielectric material of dielectric constant dk 2 . Width  94  may be 0.4-0.5 mm, 0.3-0.5 mm, 0.2-0.6 mm, greater than 0.1 mm, greater than 0.3 mm, 0.2-2.0 mm, 0.3-1.0 mm, or greater than between 0.4 and 0.5 mm, just as a few examples. 
     Dielectric resonating element  68  may radiate radio-frequency signals  84  when excited by the signal conductor for radio-frequency transmission lines  88 V and/or  88 H. In some scenarios, a slot is formed in ground traces on substrate  72 , the slot is indirectly fed by a signal conductor embedded within substrate  72 , and the slot excites dielectric resonating element  68  to radiate radio-frequency signals  84 . However, in these scenarios, the radiating characteristics of the antenna may be affected by how the dielectric resonating element is mounted to substrate  72 . For example, air gaps or layers of adhesive used to mount the dielectric resonating element to the flexible printed circuit can be difficult to control and can undesirably affect the radiating characteristics of the antenna. In order to mitigate the issues associated with exciting dielectric resonating element  68  using an underlying slot, antenna  40  may be fed using one or more radio-frequency feed probes  100  such as feed probes  100 V and  100 H of  FIG.  6   . Feed probes  100  may form part of the antenna feeds for antenna  40  (e.g., antenna feed  44  of  FIG.  3   ). 
     As shown in  FIG.  6   , feed probe  100 V may be formed from conductive structure  86 V and feed probe  100 H may be formed from conductive structure  86 H. Conductive structure  86 V may include a first portion patterned onto or pressed against a first sidewall  102  of dielectric resonating element  68 . If desired, conductive structure  86 V may also include a second portion on the surface of substrate  72  and the second portion may be coupled to the signal traces of radio-frequency transmission line  88 V (e.g., using solder, welds, conductive adhesive, etc.). The second portion of conductive structure  86 V may be omitted if desired (e.g., the signal traces in radio-frequency transmission line  88 V may be soldered directly to the portion of conductive structure  86 V on the first sidewall  102 ). Conductive structure  86 V may include conductive traces patterned directly onto the first sidewall  102  or may include stamped sheet metal in scenarios where conductive structure  86 V is pressed against the first sidewall  102 , as examples. 
     The signal traces in radio-frequency transmission line  88 V may convey radio-frequency signals to and from feed probe  100 V. Feed probe  100 V may electromagnetically couple the radio-frequency signals on the signal traces of radio-frequency transmission line  88 V into dielectric resonating element  68 . This may serve to excite one or more electromagnetic modes (e.g., radio-frequency cavity or waveguide modes) of dielectric resonating element  68 . When excited by feed probe  100 V, the electromagnetic modes of dielectric resonating element  68  may configure the dielectric resonating element to serve as a waveguide that propagates the wavefronts of radio-frequency signals  84  along the height of dielectric resonating element  68  (e.g., in the direction of the Z-axis and along the central/longitudinal axis  76  of dielectric resonating element  68 ). The radio-frequency signals  84  conveyed by feed probe  100 V may be vertically polarized. 
     Similarly, conductive structure  86 H may include a first portion patterned onto or pressed against a second sidewall  102  of dielectric resonating element  68 . If desired, conductive structure  86 H may also include a second portion on the surface of substrate  72  and the second portion may be coupled to the signal traces of radio-frequency transmission line  88 H (e.g., using solder, welds, conductive adhesive, etc.). The second portion of conductive structure  86 H may be omitted if desired (e.g., the signal traces in radio-frequency transmission line  88 H may be soldered directly to the conductive structure  86 H on sidewall  102 ). Conductive structure  86 H may include conductive traces patterned directly onto the second sidewall  102  or may include stamped sheet metal in scenarios where conductive structure  86 H is pressed against the second sidewall  102 , as examples. 
     The signal traces in radio-frequency transmission line  88 H may convey radio-frequency signals to and from feed probe  100 H. Feed probe  100 H may electromagnetically couple the radio-frequency signals on the signal traces of radio-frequency transmission line  88 H into dielectric resonating element  68 . This may serve to excite one or more electromagnetic modes (e.g., radio-frequency cavity or waveguide modes) of dielectric resonating element  68 . When excited by feed probe  100 H, the electromagnetic modes of dielectric resonating element  68  may configure the dielectric resonating element to serve as a waveguide that propagates the wavefronts of radio-frequency signals  84  along the height of dielectric resonating element  68  (e.g., along central/longitudinal axis  76  of dielectric resonating element  68 ). The radio-frequency signals  84  conveyed by feed probe  100 H may be horizontally polarized. 
     Similarly, during signal reception, radio-frequency signals  84  may be received by antenna  40 . The received radio-frequency signals may excite the electromagnetic modes of dielectric resonating element  68 , resulting in the propagation of the radio-frequency signals down the height of dielectric resonating element  68 . Feed probe  100 V may couple the received vertically-polarized signals onto radio-frequency transmission line  88 V. Feed probe  100 H may couple the received horizontally-polarized signals onto radio-frequency transmission line  88 H. Radio-frequency transmission lines  88 H and  88 V may pass the received radio-frequency signals to millimeter/centimeter wave transceiver circuitry (e.g., millimeter/centimeter wave transceiver circuitry  38  of  FIGS.  2  and  3   ) through the radio-frequency integrated circuit for antenna  40 . The relatively large difference in dielectric constant between dielectric resonating element  68  and dielectric substrate  70  may allow dielectric resonating element  68  to convey radio-frequency signals  84  with a relatively high antenna efficiency (e.g., by establishing a strong boundary between dielectric resonating element  68  and dielectric substrate  70  for the radio-frequency signals). The relatively high dielectric constant of dielectric resonating element  68  may also allow the dielectric resonating element  68  to occupy a relatively small volume compared to scenarios where materials with a lower dielectric constant are used. 
     The dimensions of feed probes  100 V and  100 H (e.g., height  90  and width  92  on sidewalls  102 ) may be selected to help match the impedance of radio-frequency transmission lines  88 V and  88 H to the impedance of dielectric resonating element  68 . As an example, width  92  may be between 0.3 mm and 0.7 mm, between 0.2 mm and 0.8 mm, between 0.4 mm and 0.6 mm, or other values. Height  90  may be between 0.3 mm and 0.7 mm, between 0.2 mm and 0.8 mm, between 0.4 mm and 0.6 mm, or other values. Height  90  may be equal to width  92  or may be different than width  92 . Feed probes  100 V and  100 H may sometimes be referred to herein as feed conductors, feed patches, or probe feeds. Dielectric resonating element  68  may sometimes be referred to herein as a dielectric radiating element, dielectric radiator, dielectric resonator, dielectric antenna resonating element, dielectric column, dielectric pillar, radiating element, or resonating element. When fed by one or more feed probes such as feed probes  100 V and  100 H, dielectric resonator antennas such as antenna  40  of  FIG.  6    may sometimes be referred to herein as probe-fed dielectric resonator antennas. 
     Antenna  40  may be included in a rear-facing, front-facing, or side-facing phased antenna array in device  10  (e.g., radio-frequency signals  84  may form radio-frequency signals  62  or  60  of  FIG.  5   ). In scenarios where antenna  40  is formed in a front-facing phased antenna array, top surface  80  may be pressed against, adhered to, or separated from display cover layer  56  of  FIG.  5   . In scenarios where antenna  40  is formed in a rear-facing phased antenna array, top surface  80  may be pressed against, adhered to, or separated from rear housing wall  12 R of  FIG.  5   . An optional impedance matching layer may be interposed between top surface  80  and rear housing wall  12 R or display cover layer  56 . The impedance matching layer may have a dielectric constant that is between dielectric constant dk 1  and the dielectric constant of rear housing wall  12 R or display cover layer  56 . If desired, the dielectric constant and thickness of the impedance matching layer may be selected to configure the impedance matching layer to form a quarter-wave impedance transformer for antenna  40  at the frequencies of operation of antenna  40 . This may configure the impedance matching layer to help minimize signal reflections at the interfaces between top surface  80  and free space exterior to device  10 . 
     If desired, radio-frequency transmission lines  88 V and  88 H may include impedance matching structures (e.g., transmission line stubs) to help match the impedance of dielectric resonating element  68 . Both feed probes  100 H and  100 V may be active at once so that antenna  40  conveys both vertically and horizontally polarized signals at any given time. If desired, the phases of the signals conveyed by feed probes  100 H and  100 V may be independently adjusted so that antenna  40  conveys radio-frequency signals  84  with an elliptical or circular polarization. In another suitable arrangement, a single one of feed probes  100 H and  100 V may be active at once so that antenna  40  conveys radio-frequency signals of only a single polarization at any given time. In another suitable arrangement, antenna  40  may be a single-polarization antenna where radio-frequency transmission line  88 V and feed probe  100 V have been omitted. 
     As shown in  FIG.  6   , dielectric resonating element  68  may have a height  96 , a length  74 , and a width  73 . Length  74 , width  73 , and height  96  may be selected to provide dielectric resonating element  68  with a corresponding mix of electromagnetic cavity/waveguide modes that, when excited by feed probes  100 H and/or  100 V, configure antenna  40  to radiate at desired frequencies. For example, height  96  may be 2-10 mm, 4-6 mm, 3-7 mm, 4.5-5.5 mm, or greater than 2 mm. Width  73  and length  74  may each be 0.5-1.0 mm, 0.4-1.2 mm, 0.7-0.9 mm, 0.5-2.0 mm, 1.5 mm-2.5 mm, 1.7 mm-1.9 mm, 1.0 mm-3.0 mm, etc. Width  73  may be equal to length  74  (e.g., dielectric resonating element  68  may have a square-shaped lateral profile in the X-Y plane) or, in other arrangements, may be different than length  74  (e.g., dielectric resonating element  68  may have a rectangular or non-rectangular lateral profile in the X-Y plane). Sidewalls  102  of dielectric resonating element  68  may directly contact the surrounding dielectric substrate  70 . Dielectric substrate  70  may be molded over feed probes  100 H and  100 V or may include openings, notches, or other structures that accommodate the presence of feed probes  100 H and  100 V. Each sidewall  102  may be planar or, if desired, one or more sidewall  102  may have a non-planar shape (e.g., a shape with planar and curved portions, a planar shape with a notch or recessed portion, etc.). The example of  FIG.  6    is merely illustrative and, if desired, dielectric resonating element  68  may have other shapes (e.g., shapes with any desired number of straight and/or curved sidewalls  102 ). 
     In practice, if care is not taken, dielectric resonator antennas such as antenna  40  can be subject to undesirable cross-polarization interference. Cross-polarization interference can occur when radio-frequency signals to be conveyed in a first polarization are undesirably transmitted or received using an antenna feed that is used to convey radio-frequency signals in a second polarization. For example, cross-polarization interference may involve the leakage of horizontally-polarized signals onto feed probe  100 V of  FIG.  6    (e.g., a feed probe intended to convey vertically-polarized signals) and/or the leakage of vertically-polarized signals onto feed probe  100 H of  FIG.  6    (e.g., a feed probe intended to convey horizontally-polarized signals). The cross-polarization interference can arise when the electric field produced by feed probe  100 V has components oriented at a mix of different angles or when the electric field produced by feed probe  100 H has components oriented at a mix of different angles within dielectric resonating element  68 . Cross-polarization interference can lead to a decrease in overall data throughput, errors in the transmitted or received data, or otherwise degraded antenna performance. These effects are also particularly detrimental in scenarios where antenna  40  conveys independent data streams using horizontal and vertical polarizations (e.g., under a MIMO scheme), as the cross-polarization interference reduces the independence of the data streams. It would therefore be desirable to be able to provide a dielectric resonator antenna such as antenna  40  with structures for mitigating cross polarization interference (e.g., for maximizing isolation between polarizations handled by the antenna). 
       FIG.  7    is a top-down view of antenna  40  having structures for mitigating cross polarization interference. In the example of  FIG.  7   , antenna  40  is a dual-polarization dielectric resonator antenna having feed probes  100 V and  100 H for exciting different polarizations of dielectric resonating element  68 . 
     As shown in  FIG.  7   , dielectric resonating element  68  may have a rectangular lateral profile. Dielectric resonating element  68  may have four sidewalls  102  (e.g., four vertical faces or surfaces oriented perpendicular to the X-Y plane) such as a first sidewall  102 A, a second sidewall  102 B, a third sidewall  102 C, and a fourth sidewall  102 D. Third sidewall  102 C may oppose first sidewall  102 A and fourth sidewall  102 D may oppose second sidewall  102 B on dielectric resonating element  68 . Conductive structure  86 V of feed probe  100 V may be patterned onto or pressed against first sidewall  102 A. Conductive structure  86 V may also be coupled to conductive trace  106 V on the underlying substrate  72  (e.g., using solder, welds, conductive adhesive, etc.). Conductive trace  106 V may be coupled to conductive trace  104 V. Conductive traces  104 V and  106 V may form part of the signal conductor for radio-frequency transmission line  88 V of  FIG.  6   . Similarly, conductive structure  86 H of feed probe  100 H may be patterned onto or pressed against second sidewall  102 B. Conductive structure  86 H may also be coupled to conductive trace  106 H on substrate  72  (e.g., using solder, welds, conductive adhesive, etc.). Conductive traces  106 H may be coupled to conductive trace  104 H. Conductive traces  104 H and  106 H may form part of the signal conductor for radio-frequency transmission line  88 H of  FIG.  6   . 
     In order to mitigate cross polarization interference, parasitic elements such as parasitic elements  108 H and  108 V may be patterned onto the sidewalls of dielectric resonating element  68 . Parasitic elements  108 H and  108 V may, for example, be formed from floating patches of conductive material patterned onto or pressed against the sidewalls of dielectric resonating element  68  (e.g., conductive patches that are not coupled to ground or the signal traces for antenna  40 ). As shown in  FIG.  7   , parasitic element  108 H may be patterned onto or pressed against fourth sidewall  102 D opposite feed probe  100 H. Parasitic element  108 V may be patterned onto or pressed against third sidewall  102 C opposite first feed probe  100 V. 
     The presence of the conductive material in parasitic element  108 H may serve to change the boundary condition for the electric field excited by feed probe  100 H within dielectric resonating element  68 . For example, in scenarios where parasitic element  108 H is omitted, the electric field excited by feed probe  100 H may include a mix of different electric field components oriented in different directions. This may lead to cross-polarization interference in which some vertically-polarized signals undesirably leak onto feed probe  100 H. However, the boundary condition created by parasitic element  108 H may serve to align the electric field excited by feed probe  100 H in a single direction between sidewalls  102 B and  102 D, as shown by arrows  112  (e.g., in a horizontal direction parallel to the X-axis). Because the entire electric field excited by feed probe  100 H is horizontal, feed probe  100 H may only convey horizontally-polarized signals without vertically-polarized signals interfering with the horizontally-polarized signals. 
     Similarly, the presence of the conductive material in parasitic element  108 V may serve to change the boundary condition for the electric field excited by feed probe  100 V within dielectric resonating element  68 . For example, in scenarios where parasitic element  108 V is omitted, the electric field excited by feed probe  100 V may include a mix of different electric field components oriented in different directions. This may lead to cross-polarization interference in which some horizontally-polarized signals undesirably leak onto feed probe  100 V. However, the boundary condition created by parasitic element  108 V may serve to align the electric field excited by feed probe  100 V in a single direction between sidewalls  102 A and  102 C, as shown by arrows  110  (e.g., in a vertical direction parallel to the Y-axis). Because the entire electric field excited by feed probe  100 V is vertical, feed probe  100 V may only convey vertically-polarized signals without horizontally-polarized signals interfering with the vertically-polarized signals. 
     Parasitic element  108 V may have a shape (e.g., lateral dimensions in the X-Z plane) that matches the shape of the portion of conductive structure  86 V on sidewall  102 A (e.g., parasitic element  108 V may have width  92  and height  90  of  FIG.  6   . Similarly, parasitic element  100 H may have a shape (e.g., lateral dimensions in the Y-Z plane) that matches the shape of the portion of conductive structure  86 H on sidewall  102 B (e.g., parasitic element  108 H may have width  92  and height  90  of  FIG.  6   ). This may ensure that there are symmetric boundary conditions between feed probe  100 V and parasitic element  108 V and between feed probe  100 H and parasitic element  108 H. Parasitic element  108 V need not have the same exact dimensions as feed probe  100 V and parasitic element  108 H need not have the same exact dimensions as feed probe  100 H if desired. 
     Antenna  40  may also include cross-polarization interference mitigating parasitic elements in scenarios where antenna  40  is fed using only a single feed probe.  FIG.  8    is a top-down view showing how antenna  40  may include cross-polarization interference mitigating parasitic elements in an arrangement where antenna  40  is fed using only a single feed probe  100 . 
     As shown in  FIG.  8   , antenna  40  may be fed using a single feed probe  100 . Conductive structure  86  of feed probe  100  may be patterned onto sidewall  102 A of dielectric resonating element  68 . Conductive structure  86  may be coupled to conductive trace  104  on the underlying substrate  72 . Ground traces such as ground traces  116  may also be patterned onto substrate  72 . 
     Antenna  40  may include one or more parasitic elements  114  such as a first parasitic element  114 - 1  and a second parasitic element  114 - 2 . Parasitic element  114 - 1  may be formed from a patch of conductive traces (e.g., a conductive patch) that is patterned onto sidewall  102 D of dielectric resonating element  68 . Parasitic element  114 - 2  may be formed from a patch of conductive traces (e.g., a conductive patch) that is patterned onto sidewall  102 B of dielectric resonating element  68 . Parasitic elements  114 - 1  and  114 - 2  may each have the same size and lateral dimensions (e.g., in the Y-Z plane) as conductive structure  86  (e.g., in the X-Z plane), for example. Parasitic element  114 - 1  and parasitic element  114 - 2  may each be coupled to ground traces  116  at substrate  72  by conductive interconnect structures  118 . Conductive interconnect structures  118  may include solder, welds, conductive adhesive, conductive tape, conductive foam, conductive springs, conductive brackets, and/or any other desired conductive interconnect structures. In this way, parasitic elements  114 - 1  and  114 - 2  may each be held at a ground potential (e.g., parasitic elements  114 - 1  and  114 - 2  may be grounded patches). Parasitic element  114 - 1  may be omitted or parasitic element  114 - 2  may be omitted if desired (e.g., antenna  40  may include only a single parasitic element  114  if desired). 
     Parasitic element  114 - 1  and/or parasitic element  114 - 2  may serve to alter the electromagnetic boundary conditions of dielectric resonating element  68  to mitigate cross-polarization interference for feed probe  100  (e.g., to isolate feed probe  100  from interference from horizontally-polarized signals in scenarios where feed probe  100  handles vertically-polarized signals). Sidewall  102 C of dielectric resonating element  68  may be free from conductive material such as parasitic elements  114 . 
     Phased antenna array  54  of  FIG.  4    (e.g., a front-facing phased antenna array for conveying radio-frequency signals  62  through display cover layer  56  of  FIG.  5   , a rear-facing phased antenna array for conveying radio-frequency signals  60  through rear housing wall  12 R of  FIG.  5   , or a side-facing phased antenna array) may include any desired number of antennas  40  arranged in any desired pattern (e.g., a pattern having rows and columns). Each of the antennas  40  in phased antenna array  54  may be dielectric resonator antenna such as the probe-fed dielectric resonator antenna  40  of  FIGS.  6 - 8    (e.g., having two feed probes  100 V and  100 H as shown in  FIG.  6    and optionally parasitic elements  108 V and  108 H as shown in  FIG.  7    or having one feed probe  100  and optionally parasitic elements  114 - 1  and  114 - 2  as shown in  FIG.  8   ). Phased antenna array  54  may be formed as a part of an integrated antenna module. 
       FIG.  9    is a top down view of an integrated antenna module that may include phased antenna array  54 . As shown in  FIG.  9   , phased antenna array  54  may be formed as a part of an integrated antenna module such as antenna module  120 . Antenna module  120  may include substrate  72 . Phased antenna array  54  may be mounted to a surface of substrate  72  such as surface  122 . A board-to-board connector such as connector  123  may also be mounted to surface  122 . 
     In the example of  FIG.  9   , phased antenna array  54  is a dual-band phased antenna array having a first set of antennas  40 L that convey radio-frequency signals in a first frequency band and a second set of antennas  40 H that convey radio-frequency signals in a second frequency band that is higher than the first frequency band. Antennas  40 H may therefore sometimes be referred to herein as high band antennas  40 H whereas low band antennas  40 L are sometimes referred to herein as low band antennas  40 L. As just one example, the first frequency band may include frequencies between about 24 and 31 GHz and the second frequency band may include frequencies between about 37 and 41 GHz. 
     High band antennas  40 H may be dielectric resonator antennas having dielectric resonating elements  68 H embedded within dielectric substrate  70 . Low band antennas  40 L may be dielectric resonator antennas having dielectric resonating elements  68 H embedded within dielectric substrate  70 . Dielectric substrate  70  may be molded over and/or around dielectric resonating elements  68 H and  68 L and may be mounted to surface  122  of substrate  72 . In order to support satisfactory beam forming, each high band antenna  40 H may, for example, be separated from one or two adjacent high band antennas  40 H in dielectric substrate  70  by a distance that is approximately equal to one-half of the effective wavelength corresponding to a frequency in the second frequency band (e.g., where the effective wavelength is equal to a free space wavelength multiplied by a constant value determined by the dielectric material surrounding the antennas). Similarly, each low band antenna  40 L may, for example, be separated from one or two adjacent low band antennas  40 L in dielectric substrate  70  by a distance that is approximately equal to one-half of the effective wavelength corresponding to a frequency in the first frequency band. 
     In the example of  FIG.  9   , phased antenna array  54  is a one-dimensional array having four high band antennas  40 H interleaved (interspersed) with four low band antennas  40 L arranged along a single longitudinal axis (e.g., running parallel to the X-axis). This is merely illustrative. Phased antenna array  54  may include any desired number of low band antennas  40 L and/or high band antennas  40 H and the antennas may be arranged in any desired one or two-dimensional pattern. 
       FIG.  10    is a cross-sectional side view of antenna module  120  (e.g., as taken in the direction of line AA′ of  FIG.  9   ). As shown in  FIG.  10   , the bottom surface  82  of the dielectric resonating elements  68 L and  68 H in phased antenna array  54  may be mounted to surface  122  of substrate  72 . Dielectric substrate  70  may be molded over dielectric resonating elements  68 L and  68 H and may be mounted to surface  122 . If desired, dielectric substrate  70  may be molded over every dielectric resonating element  68 L and  68 H in phased antenna array  54  to form a single integrated structure, and the single integrated structure may then be mounted (e.g., surface-mounted) to surface  122  of substrate  72 . This may, for example, minimize mechanical variations between the antennas in phased antenna array  54  that could otherwise deteriorate antenna performance or mechanical reliability. 
     Substrate  72  may have a surface  124  opposite surface  122 . Additional electronic components such as radio-frequency integrated circuit (RFIC) 126  may be mounted to surface  124  of substrate  72 . An optional over-mold and/or shielding structures may be provided over RFIC  126  and surface  124  of substrate  72  (not shown in the example of  FIG.  10    for the sake of clarity). RFIC  126  may have terminals or ports that are coupled to corresponding contact pads on surface  124  using solder balls, conductive adhesive, conductive pins, conductive springs, and/or any other desired conductive interconnect structures. 
     Radio-frequency transmission lines in substrate  72  (e.g., radio-frequency transmission lines  88 V and  88 H of  FIG.  6   ) may couple the ports of RFIC  126  to the feed probes (e.g., feed probes  100 V and  100 H of  FIG.  6   ) on dielectric resonating elements  68 L and  68 H. Dielectric substrate  72  may include multiple stacked dielectric substrate layers (e.g., layers of printed circuit board material, flexible printed circuit material, ceramic, etc.). The radio-frequency transmission lines in substrate  72  may include signal traces and ground traces on one or more of the stacked dielectric substrate layers (e.g., embedded within and/or on surfaces  122  and/or  124  of substrate  72 ) and/or conductive vias extending through one or more of the stacked dielectric substrate layers. 
     RFIC  126  may include, for example, phase and magnitude controllers  50  of  FIG.  4   , up-converter circuitry, down-converter circuitry, amplifier circuitry, or any other desired radio-frequency circuitry. RFIC  126  may include one or more additional ports or terminals that are coupled to connector  123  of  FIG.  9    (e.g., using additional radio-frequency transmission line structures on substrate  72 ). RFIC  126  may be coupled to millimeter/centimeter wave transceiver circuitry  38  of  FIGS.  2  and  3    via connector  123 . Millimeter/centimeter wave transceiver circuitry  38  may be mounted to an additional substrate such as an additional rigid printed circuit board, a flexible printed circuit, the main logic board of device  10 , etc. If desired, the signals conveyed between the millimeter/centimeter wave transceiver circuitry and RFIC  126  may be at an intermediate frequency (e.g., a radio frequency) that is greater than a baseband frequency and less than the frequencies with which antennas  40 L and  40 H convey radio-frequency signals. In these scenarios, upconverter circuitry in RFIC  126  may up-convert the signals from the intermediate frequency to the frequencies of operation of antennas  40 L and  40 H. Similarly, downconverter circuitry in RFIC  126  may down-convert signals received by antennas  40 L and  40 H to the intermediate frequency. RFIC  126  may, if desired, include multiple separate (discrete) radio-frequency integrated circuits mounted to substrate  72  (e.g., antenna module  120  may be an integrated circuit package that includes one or more RFICs and one or more phased antenna arrays mounted to a common/shared substrate such as substrate  72 ). 
       FIG.  11    is a perspective view of the antenna module  120  of  FIGS.  9  and  10   . As shown in  FIG.  11   , phased antenna array  54  (e.g., dielectric resonating elements  68 L and  68 H and dielectric substrate  70 ) may be mounted to surface  122  of substrate  72 . Dielectric substrate  70  may have a foot structure  128  at surface  122  that is wider than the top surface of dielectric substrate  70  (e.g., to increase the mechanical stability of antenna module  120 ). If desired, phased antenna array  54  may be secured to surface  122  using a layer of adhesive. Underfill may be provided under dielectric substrate  70  and phased antenna array  54  if desired. In the example of  FIG.  11   , a dielectric over-mold structure such as over-mold  131  is provided on surface  124  of substrate  72 . Over-mold  131  may cover RFIC  126  of  FIG.  10    (e.g., RFIC  126  may be embedded within over-mold  131 , thereby hiding RFIC  126  from view in  FIG.  11   ). Over-mold  131  may serve to protect RFIC  126  from damage or contaminants, may perform heat dissipation, isolation, shielding, etc. Phased antenna array  54  may be mounted within peripheral region  66  of  FIG.  5    and may convey radio-frequency signals through the front or rear face of device  10 , as examples. 
     In the example of  FIGS.  9 - 11   , RFIC  126  is mounted to the opposite side of substrate  72  as phased antenna array  54 . This is merely illustrative. In another suitable arrangement, RFIC  126  may be mounted to the same side of substrate  72  as phased antenna array  54 .  FIG.  12    is a top-down view showing how RFIC  126  may be mounted to the same side of substrate  72  as phased antenna array  54 . 
     As shown in  FIG.  12   , RFIC  126  and phased antenna array  54  may both be mounted to surface  122  of substrate  72 . Some or all of RFIC  126  may, for example, be laterally interposed between phased antenna array  54  and a peripheral edge of substrate  72 .  FIG.  13    is a side view of antenna module  120  as taken in the direction of arrow  132  of  FIG.  12   . As shown in  FIG.  13   , phased antenna array  54  may be taller in the direction of the Z-axis than RFIC  126 . This may, for example, allow RFIC  126  to rest under display module  64  while phased antenna array  54  radiates through display cover layer  56  (e.g., in scenarios where antenna module  120  is mounted within peripheral region  66  of  FIG.  5    and phased antenna array  54  is a front-facing phased antenna array in device  10 ). 
     If desired, antenna module  120  may include multiple phased antenna arrays mounted to different sides of substrate  72 .  FIG.  14    is a side view showing how multiple phased antenna arrays  54  may be mounted to different sides of substrate  72 . As shown in  FIG.  14   , antenna module  120  may include a first phased antenna array  54 - 1  and a second phased antenna array  54 - 2 . First phased antenna array  54 - 1  may include antennas  40  with dielectric resonating elements  68  mounted to surface  122  of substrate  72  whereas second phased antenna array  54 - 2  includes antennas  40  with dielectric resonating elements  68  mounted to surface  124  of substrate  72 . First phased antenna array  54 - 1  may steer a beam of radio-frequency signals  134  across at least some of the hemisphere above surface  122 . Second phased antenna array  54 - 2  may steer a beam of radio-frequency signals  136  across at least some of the hemisphere below surface  124 . First phased antenna array  54 - 1  may be a one-dimensional array or a two-dimensional array of antennas  40 . Second phased antenna array  54 - 2  may be a one-dimensional array or a two-dimensional array of antennas  40 . 
     Antenna module  120  of  FIG.  14    may, for example, be mounted within peripheral region  66  of  FIG.  5   . First phased antenna array  54 - 1  may be a front-facing phased antenna array (e.g., where radio-frequency signals  134  serve as the radio-frequency signals  62  conveyed through display cover layer  56  of  FIG.  5   ). Second phased antenna array may be a rear-facing phased antenna array (e.g., e.g., where radio-frequency signals  136  serve as the radio-frequency signals  60  conveyed through rear housing wall  12 R of  FIG.  5   ). In another suitable arrangement, first phased antenna array  54 - 1  may be a rear-facing phased antenna array whereas second phased antenna array  54 - 2  is a front-facing phased antenna array. 
     As shown in  FIG.  14   , connector  123  may be mounted to surface  122 . This is merely illustrative and, in another suitable arrangement, connector  123  may be mounted to surface  124 . RFIC  126  may be mounted to surface  124 . This is merely illustrative and, in another suitable arrangement, RFIC  126  may be mounted to surface  122 . RFIC  126  and connector  123  may be mounted to the same surface if desired. Radio-frequency transmission lines in substrate  72  may couple RFIC  126  to each of the antennas  40  in phased antenna arrays  54 - 1  and  54 - 2 . An over-mold structure may be provided over RFIC  126  and surface  124  if desired. In the example of  FIG.  14   , phased antenna arrays  54 - 1  and  54 - 2  are shown without a corresponding dielectric substrate  70  ( FIGS.  6  and  9 - 13   ) for the sake of clarity. If desired, dielectric substrates  70  may be molded over first phased antenna array  54 - 1  and/or second phased antenna array  54 - 2 . 
     The example of  FIG.  14    in which both phased antenna arrays  54 - 1  and  54 - 2  are formed from dielectric resonator antennas is merely illustrative. In another suitable arrangement, the antennas in first phased antenna array  54 - 1  may be stacked patch antennas, as shown in the cross-sectional side view of  FIG.  15   . 
     As shown in  FIG.  15   , the antennas  40  in first phased antenna array  54 - 1  may be stacked patch antennas. Each antenna  40  in first phased antenna array  54 - 1  may include one or more conductive patches  140  embedded within the dielectric layers  138  of substrate  72 . Conductive patches  140  may be spaced apart from and extend parallel to ground traces  144  in substrate  72 . The conductive patches  140  in antennas  40  may include directly-fed patch antenna resonating elements and/or indirectly-fed parasitic antenna resonating elements that at least partially overlap at least one directly-fed patch antenna resonating element. Conductive patches  140  may have lengths  142  that determine the frequency response of first phased antenna array  54 - 1 . Lengths  142  may, for example, be approximately equal to one-half the effective wavelength corresponding to a frequency in the frequency band of operation of first phased antenna array  54 - 1 . 
     In practice, the dielectric resonating elements  68  in second phased antenna array  54 - 2  may occupy greater height (e.g., in the direction of the Z-axis) than conductive patches  140  in first phased antenna array  54 - 1 . At the same time, conductive patches  140  may occupy greater area (e.g., in the X-Y plane) than dielectric resonating elements  68 . This may allow antenna module  120  to be mounted within device  10  at locations where there may be more space to place antennas for radiating through one side of device  10  than the other. As an example, antenna module  120  of  FIG.  15    may be mounted within peripheral region  66  of  FIG.  5    with second phased antenna array  54 - 2  facing display cover layer  56  and first phased antenna array  54 - 1  facing rear housing wall  12 R (e.g., there may be more space to place antennas for radiating through rear housing wall  12 R than through display cover layer  56  due to the presence of display module  64 ). The example of  FIG.  15    is merely illustrative and, in another suitable arrangement, first phased antenna array  54 - 1  may include dielectric resonator antennas whereas second phased antenna array  54 - 2  is includes stacked patch antennas. 
     In practice, it can be challenging to manufacture antenna modules having dielectric resonator antennas such as antenna module  120  of  FIGS.  9 - 15   . In some scenarios, antenna modules are manufactured by individually forming each dielectric resonating element (e.g., by sintering a ceramic powder), individually metallizing the probe feed for each dielectric resonating element, injection molding the dielectric substrate over each individually-formed dielectric resonating element in the array, grinding down the portion of the dielectric resonating elements protruding beyond the dielectric substrate, and surface-mounting the result to a board. This process can be very complicated, time consuming, and expensive, and can lead to antenna modules that exhibit a substantial amount of mechanical variation that limits the overall mechanical and/or wireless performance of the module (e.g., due to poor dielectric resonating element parallelism, height coplanarity, and dimension, contact pad tolerance issues, and unpredictable dielectric resonating element tilting). In order to mitigate these issues, antenna module  120  may be manufactured using a largely scalable, IC-assembly process compatible, double side molding process, as shown in  FIGS.  16  and  17   . 
       FIGS.  16  and  17    are diagrams of an illustrative assembly process for antenna module  120 . As shown in  FIG.  16   , antenna modules  120  may be manufactured in a manufacturing system such as manufacturing system  146 . Manufacturing system  146  may include manufacturing equipment  148 . Manufacturing system  146  may gather substrate  72  and electronic components  150  to be assembled into a given antenna module  120 . Substrate  72  may include radio-frequency transmission line structures (e.g., signal and ground traces on or embedded within the dielectric layers of substrate  72 ) and corresponding contact pads coupled to the radio-frequency transmission line structures at the surfaces of substrate  72 . Electronic components  150  may include RFIC  126  ( FIGS.  9 - 15   ) or any other desired radio-frequency components (e.g., radio-frequency switching circuits, filter circuits, discrete capacitors, resistors, and inductors, amplifier circuits, etc.). 
     Manufacturing equipment  148  may surface mount electronic components  150  to surface  122  of substrate  72 , as shown by arrow  152  (e.g., using surface-mount technology (SMT) equipment in manufacturing equipment  148 ). For example, solder balls  154  or any other desired conductive interconnect structures may be used to couple the terminals (ports) of electronic components  150  to corresponding contact pads on surface  122  of substrate  72 . Manufacturing equipment  148  may then layer over-mold  131  over the surface-mounted components  150  and surface  122  of substrate  72 , as shown by arrow  156 . This may serve to encapsulate or embed electronic components  150  at surface  122  within over-mold  131 . 
     Manufacturing equipment  148  may then flip substrate  72  over and each dielectric resonating element  68  in the antenna module may be concurrently formed on surface  124  of substrate  72 . For example, manufacturing equipment  148  may form dielectric resonating elements  68  by performing a molding/selective molding process using high dielectric constant epoxy mold compound material to mold each of the dielectric resonating elements  68  in the module at once (e.g., so that dielectric resonating elements  68  exhibit dielectric constant dk 1  of  FIG.  6   ). This process may also form a top-most layer  164  on surface  124  of substrate  72 . Top-most layer  164  may cover the contact pads at surface  124  for the radio-frequency transmission lines used to feed dielectric resonating elements  68  (e.g., radio-frequency transmission lines  88 V and  88 H of  FIG.  6   ). While top-most layer  164  may be formed from the same material as dielectric resonating elements  68 , top-most layer  164  may sometimes be referred to herein as forming a part of substrate  72  or forming the top-most layer of substrate  72 . 
     Manufacturing equipment  148  may then perform laser activation and metallization for dielectric resonating elements  68  (e.g., using a laser direct structuring (LDS) process), as shown by arrow  162 . For example, lasers in manufacturing equipment  148  may be used to create a pattern or seed layer for the metallization of the feed probes and optionally the parasitic elements for antennas  40  (e.g., on sidewalls  102  of dielectric resonating elements  68  and/or on top-layer  164 ). Manufacturing equipment  148  may then perform a physical deposition or chemical plating process that metalizes the pattern or seed layer created by the lasers. This may serve to form conductive structures  86 V and  86 H on sidewalls  102  of dielectric resonating elements  68  (e.g., at bottom surface  82  of dielectric resonating elements  68 ) and/or on top-most layer  164 . If desired, this process may also be used to form parasitic elements  108 H and  108 V ( FIG.  7   ) and/or parasitic elements  114 - 1  and  114 - 2  ( FIG.  8   ) on sidewalls  102  and/or top-most layer  164 . In scenarios where dielectric resonating elements  68  only cover a single polarization, manufacturing equipment  148  may form only a single feed probe on each dielectric resonating element  68 . 
     In addition, manufacturing equipment  148  may couple conductive structures  86 V and  86 H to corresponding contact pads on surface  124  of substrate  72  (e.g., by forming conductive vias that extend through top-most layer  164 ). In scenarios where parasitic elements  114 - 1  and/or  114 - 2  of  FIG.  8    are formed, manufacturing equipment  148  may form conductive vias through top-most layer  164  to couple the parasitic elements to ground traces at surface  124 . Coupling conductive structures  86 V and  86 H to the contact pads on surface  124  may serve to couple conductive structures  86 V and  86 H to corresponding radio-frequency transmission lines in substrate  72 . The radio-frequency transmission lines may couple conductive structures  86 V and  86 H to electronic components  150  at surface  122 . 
     If desired, multiple antenna modules  120  may be manufactured from the same substrate  72 , as shown in the perspective view of  FIG.  17   . As shown in  FIG.  17   , substrate  72  may be used to form nine antenna modules each having four antennas and thus four dielectric resonating elements  68  arranged in a 1×4 pattern. This example is merely illustrative and, in general, any desired number of antenna modules may be formed from the same substrate  72 . The processes of  FIG.  16    may be performed concurrently for each of the antenna modules formed from substrate  72 . Concurrently manufacturing multiple antenna modules in this way may increase the reliability of the antenna modules (both within each antenna module and between antenna modules) and reduce the cost and time required to manufacture multiple devices  10 . This process may allow antenna module  120  to exhibit a smaller form factor for multiple applications, may eliminate extra injection molding, sintering, surface-mounting, and underfilling relative to arrangements where each dielectric resonating element is individually molded and then mounted to a substrate. This arrangement may also allow for tighter process control and improved yield relative to arrangements where each dielectric resonating element is individually molded and then mounted to a substrate. 
     As by arrow  166 , manufacturing equipment  148  may surface-mount connectors  123  to connector contact pads  168  at surface  124  of substrate  72 . Connectors  123  may couple electronic components  150  in over-mold  131  to transceiver circuitry on a separate substrate after the antenna modules are assembled into device  10 , for example. Cutting equipment (e.g., blade or laser cutting tools) in manufacturing equipment  148  may then dice (cut) substrate  72  into separate antenna modules, as shown by arrow  170 . In the example of  FIG.  17   , this may produce nine separate strips of substrate  72  that form nine separate antenna modules  120 , each having four antennas  40  with corresponding dielectric resonating elements  68 . Dielectric structure  70  may be molded over dielectric resonating elements  68  after dicing, at any other desired time after conductive structures  86 H and  86 V have been formed on dielectric resonating elements  68 , or may be omitted if desired. 
       FIG.  18    is a flow chart of illustrative steps that may be performed by manufacturing equipment  148  of  FIGS.  16  and  17    in manufacturing antenna module  120 . At step  172 , manufacturing equipment  148  may surface-mount electronic components  150  (e.g., one or more radio-frequency integrated circuits) to a surface of substrate  72  (e.g., as shown by arrow  152  of  FIG.  16   ). Manufacturing equipment  148  may layer over-mold  131  over the surface-mounted electronic components  150  (e.g., as shown by arrow  156  of  FIG.  16   ). 
     At step  174 , manufacturing equipment  148  may mold dielectric resonating elements  68  on a surface of substrate  72  (e.g., as shown by arrow  160  of  FIG.  16   ). Dielectric resonating elements  68  may be molded onto the surface of substrate  72  opposite to the surface-mounted electronic components  150 . This is merely illustrative and, if desired, dielectric resonating elements  68  may be molded onto the same surface of substrate  72  as the surface-mounted electronic components  150  (e.g., as shown in  FIGS.  12  and  13   ). 
     At step  176 , manufacturing equipment  148  pattern conductive traces onto dielectric resonating elements  68  (e.g., as shown by arrow  162  of  FIG.  16   ). Manufacturing equipment  148  may, for example, use lasers to activate or create a seed layer on dielectric resonating elements  68 . Manufacturing equipment  148  may then deposit conductive material over the activated portions of dielectric resonating elements  68 . The conductive material may form conductive structures  86 V and  86 H (e.g., for feed probes  100 V and  100 H of  FIG.  6   ) and/or parasitic elements for the antennas. 
     At step  178 , manufacturing equipment  148  may surface-mount connectors  123  onto the connector contact pads  168  of substrate  72  (e.g., as shown by arrow  166  of  FIG.  17   ). 
     At step  180 , manufacturing equipment  148  may dice substrate  180  into individual antenna modules  120  and may add corresponding shielding structures to the antenna modules (e.g., as shown by arrow  170  of  FIG.  17   ). The shielding may serve to isolate electronic components  150  from electromagnetic interference, for example. 
     At step  182 , manufacturing equipment  148  may assemble a manufactured antenna module  120  into device  10 . For example, manufacturing equipment  148  may mount antenna module  120  within peripheral region  66  of  FIG.  5    or elsewhere within the interior of device  10 . Antenna module  120  may be mounted to convey radio-frequency signals through display cover layer  56  or rear housing wall  12 R of  FIG.  5   , for example. The steps of  FIG.  18    are merely illustrative and, if desired, other processes may be used to manufacture antenna module  120 . 
     In practice, implementation of dielectric resonator antennas in electronic devices can be challenging since the dielectric resonator antennas have high aspect ratios that make it difficult to control system alignment, reliability, and interconnect reliability. In other phased antenna arrays, each antenna may require two radio-frequency connectors to feed, which can be undesirably bulky. Integrating the dielectric resonator antennas into antenna module  120  may allow the antennas to each be fed without requiring as many connectors and may allow the antennas to be properly aligned with a high degree of reliability. 
     In practice, the metallization used to feed dielectric resonating elements  68  can be costly to perform at scale. In another suitable arrangement, the feed probes for dielectric resonating elements  68  may be pressed against dielectric resonating elements  68  using feed probe biasing structures. This may allow the antennas to be fed without additional metalizations on the ceramic, which may decrease cost and design complexity. 
       FIG.  19    is a perspective view of an illustrative antenna module  120  having feed probes that are pressed against dielectric resonating elements  68  using feed probe biasing structures. In the example of  FIG.  19   , substrate  72  is a flexible printed circuit. Phased antenna array  54  may include dielectric resonating elements  68  embedded within dielectric substrate  70  to form antenna package  184 . Antenna package  184  may then be surface-mounted to contact pads on surface  122  of substrate  72 . In the example of  FIG.  19   , phased antenna array  54  includes two low band antennas  40 L interleaved with two high band antennas  40 H (e.g., in a 1×4 array). This is merely illustrative and, in general, phased antenna array  54  may include any desired number of antennas for covering any desired frequency bands. The antennas may be arranged in any desired pattern. 
     As shown in  FIG.  19   , the dielectric resonating element  68 H in high band antennas  40 H may be separated from the dielectric resonating element  68 L in one or two adjacent low band antennas  40 L by distance  192 . Distance  192  may be selected to provide satisfactory electromagnetic isolation between low band antennas  40 L and high band antennas  40 H. Each dielectric resonating element in phased antenna array  54  may be fed by feed probes having conductive structures  86 V and  86 H. Conductive structures  86 V and  86 H may be pressed against dielectric resonating elements  68  by feed probe biasing structures in antenna package  184  (not shown in  FIG.  19    for the sake of clarity). The feed probe biasing structures may, for example, press or bias conductive structure  86 H against the sidewalls  102  of dielectric resonating elements  68  (e.g., by exerting a biasing force in the −X direction). Similarly, the feed probe biasing structures may press or bias conductive structure  86 V against the sidewalls  102  of dielectric resonating elements  68  (e.g., by exerting a biasing force in the +Y direction). 
     Dielectric substrate  70  may be molded over the feed probe biasing structures as well as dielectric resonating elements  68 . Dielectric substrate  70  may have a bottom surface  188  at substrate  72  and an opposing top surface  190 . In the example of  FIG.  19   , the top surface  80  of dielectric resonating elements  68  protrudes above top surface  190  of dielectric substrate  70 . This is merely illustrative and, if desired, top surface  190  may lie flush with the top surface  80 . In another suitable arrangement, dielectric substrate  70  may cover the top surface  80  of dielectric resonating elements  70 . An attachment structure  186  may be partially embedded within dielectric substrate  70  (e.g., dielectric substrate  70  may be molded over part of attachment structure  186 ). Attachment structure  186  may help to secure antenna module  120  in place within device  10  if desired (e.g., using screws, pins, or other structures that extend through an opening in attachment structure  186 ). 
       FIG.  20    is diagram of an illustrative assembly process for antenna module  120  of  FIG.  19   . As shown in  FIG.  20   , the antenna modules may be manufactured in manufacturing system  146 . Manufacturing equipment  148  may include alignment posts  194 . Alignment posts  194  may press conductive structure  86 H against a first sidewall  102  of dielectric resonating element  68  and may press conductive structure  86 V against a second (orthogonal) sidewall  102  of dielectric resonating element  68 . Conductive structures  86 H and  86 V may include stub portions  196  that lie in the X-Y plane. Conductive structures  86 H and  86 V may, for example, be stamped from pieces of sheet metal (e.g., while alignment posts press against conductive structures  86 H and  86 V, leaving behind stub portions  196 ). 
     This may allow for a tight control of the size and position of the stamped conductive structures  86 H and  86 L while minimizing gaps between the conductive structures and dielectric resonating element  68 . 
     During a first molding process (e.g., a first injection molding process), manufacturing equipment  148  may mold a feed probe biasing structure such as biasing structure  200  (sometimes referred to herein as retention structure  200 ) over sidewalls  102  and conductive structures  86 H and  86 V at bottom surface  82  of dielectric resonating element  68  (e.g., as shown by arrow  198 ). Alignment posts  194  may hold conductive structures  86 H and  86 V in place during the first molding process and may be removed once biasing structure  200  has been formed (e.g., leaving behind alignment post holes  202  in biasing structure  200 ). Once the alignment posts  194  have been removed, biasing structure  200  may hold conductive structures  86 V and  86 H in place against the sidewalls  102  of dielectric resonating element  68 . Biasing structure  200  may, for example, exert a biasing force in the −X direction against conductive structure  86 H and may exert a biasing force in the +Y direction against conductive structure  86 V. Stub portions  196  of conductive structures  86 H and  86 V may remain exposed after molding biasing structure  200  onto dielectric resonating element  68 . This may allow stub portions  196  to be coupled to corresponding contact pads at surface  122  of substrate  72  of  FIG.  19    (e.g., using solder, conductive adhesive, etc.), thereby forming the feed probes for antenna module  120 . Biasing structure  200  may have a bottom surface  206 . Bottom surface  206  may lie flush with bottom surface  82  of dielectric resonating element  68 . 
     This process may be performed for each antenna in antenna module  120 . Dielectric substrate  70  may subsequently be molded over each of the dielectric resonating elements  68 , the corresponding biasing structures  200 , and attachment structure  186  (e.g., using a second injection molding process) to form antenna package  184 , as shown by arrow  204 . For example, a tool in manufacturing equipment  148  may locate the over-molded dielectric substrate  70  by the plastic in biasing structures  200  to maintain the contact positions of conductive structures  86 H and  86 V. Dielectric substrate  70  may include one or more openings  208  (e.g., at locations where the tool in manufacturing equipment  148  held the dielectric resonating elements during over-molding). A spring feature on the tool may locate the top surface  80  of dielectric resonating elements  68  to prevent shifting during molding, thereby maintaining reliable coplanarity for the bottom surface  82  across each dielectric resonating element  68  in antenna package  184  (e.g., bottom surface  206  of biasing structures  200  may be coplanar with bottom surface  82  of dielectric resonating elements  68 L and  68 H, stub portions  196  of conductive structures  86 H and  86 V, and bottom surface  188  of dielectric substrate  70  across antenna package  184  with a very tight tolerance). This uniform and reliable coplanarity may allow the bottom surface of antenna package  184  to be surface-mounted to substrate  72  (thereby forming antenna module  120 ) with minimal or uniform gaps across antenna package  184 , thereby optimizing the mechanical reliability and wireless performance of antenna module  120 . Antenna module  120  may then be mounted within device  10 . 
       FIG.  21    is a top-down view showing one illustrative location where antenna module  120  may be mounted within device  10  (e.g., antenna module  120  of  FIG.  19    or other antenna modules  120  as described herein). As shown in  FIG.  21   , display module  64  in display  14  may include notch  8 . Display cover layer  56  of  FIG.  5    has been omitted from  FIG.  21    for the sake of clarity. Display module  64  may form active area AA of display  14  whereas notch  8  forms part of inactive area IA of display  14  ( FIG.  1   ). The edges of notch  8  may be defined by peripheral conductive housing structures  12 W and display module  64 . For example, notch  8  may have two or more edges (e.g., three edges) defined by display module  64  and one or more edges defined by peripheral conductive housing structures  12 W. 
     Device  10  may include speaker port  16  (e.g., an ear speaker) within notch  8 . If desired, device  10  may include other components  210  within notch  8 . Other components  210  may include one or more image sensors such as one or more cameras, an infrared image sensor, an infrared light emitter (e.g., an infrared dot projector and/or flood illuminator), an ambient light sensor, a fingerprint sensor, a capacitive proximity sensor, a thermal sensor, a moisture sensor, or any other desired input/output components (e.g., input/output devices  26  of  FIG.  2   ). Antenna module  120  (e.g., an antenna module having dielectric resonating elements  68 L interleaved with dielectric resonating elements  68 H for covering different frequency bands) may be mounted within device  10  (e.g., within peripheral region  66  of  FIG.  5   ) and aligned with the portion(s) of notch  8  that are not occupied by other components  210  or speaker port  16 . Antenna module  120  may be laterally interposed between two components  210  such as between an image sensor (e.g., a rear-facing camera) and an ambient light sensor, dot projector, flood illuminator, or ambient light sensor, for example. 
     Substrate  72  may extend under display module  64  to another substrate such as substrate  214  (e.g., another flexible printed circuit, a rigid printed circuit board, a main logic board, etc.). The radio-frequency transceiver circuitry for antenna module  120  may be mounted to substrate  214  if desired. Connector  123  on substrate  72  may be coupled to connector  212  (e.g., a board-to-board connector) on substrate  214 . This may allow the antennas in antenna module  120  to cover at least some of the hemisphere over the front face of device  10  without occupying an excessive amount of space within device  10 , for example. The example of  FIG.  21    is merely illustrative and, in general, antenna module  120  may be mounted at any desired location within device  10 . Antenna module  120  may have any desired number of antennas for covering any desired frequency bands. The antennas in antenna module  120  may be arranged in any desired one or two-dimensional pattern. 
     In order to further increase isolation between adjacent antennas  40  in phased antenna array  54 , each dielectric antenna resonating element in the array may be rotated relative to as shown in  FIGS.  9 - 21   .  FIG.  22    is a top view showing how phased antenna array  54  may include rotated dielectric antenna resonating elements. 
     As shown in  FIG.  22   , antenna module  120  may include dielectric resonating elements  68 H and  68 L that are arranged in a one-dimensional pattern along longitudinal axis  216  (e.g., an axis running through the central/longitudinal axis of each of the dielectric resonating elements). Dielectric substrate  70  may be molded over dielectric resonating elements  68 H and  68 L. Prior to mounting to substrate  72 , dielectric resonating elements  68 H and  68 L may be rotated so that the sidewalls of the dielectric resonating elements (e.g., the lateral/peripheral edges of the dielectric resonating elements as viewed from above) are each oriented at a non-parallel angle with respect to longitudinal axis  216 . For example, each dielectric resonating element  68 H and  68 L may include a first pair of opposing sidewalls  102  that are oriented at angle θ with respect to longitudinal axis  216 . Each dielectric resonating element  68 H and  68 L may also include a second pair of opposing sidewalls  102  that are oriented perpendicular to the first pair of opposing sidewalls (e.g., at a 90 degree angle with respect to the first pair of opposing sidewalls or an angle of angle θ+90 degrees with respect to longitudinal axis  216 ). In this way, the sidewalls may also be oriented at a non-parallel angle with respect to each lateral edge of substrate  72 , if desired. Angle θ may be between 0 degrees and 90 degrees (e.g., 45 degrees, 30-60 degrees, 40-50 degrees, etc.). Orienting dielectric resonating elements  68 L and  68 H in this way may serve to minimize cross-coupling between adjacent antennas  40 L and  40 H, thereby maximizing isolation between the antennas and thus the radio-frequency performance of antenna module  120 . 
     In the example of  FIG.  22   , phased antenna array  54  includes four low band antennas  40 L interleaved with four high band antennas  40 H. This example is merely illustrative. In general, phased antenna array  54  may include any desired number of antennas for covering any desired bands and arranged in any desired one or two-dimensional pattern on surface  122  of substrate  72 . Connector  123  may be mounted to surface  122  or the opposing surface of substrate  72 . 
       FIG.  23    is a perspective view of the antenna module  120  of  FIG.  22   . In the example of  FIGS.  22  and  23   , the RFIC for antenna module  120  is mounted to surface  124  of substrate  72  and over-mold  131  is layered under surface  124  and the RFIC. This is merely illustrative and, in another suitable arrangement, the RFIC may be mounted to surface  122  (e.g., as shown in  FIGS.  12  and  13   ). 
     As shown in  FIG.  23   , feed probe biasing structures such as biasing structures  218  may press the feed probes for phased antenna array  54  against dielectric resonating elements  68 L and  68 H (e.g., by exerting biasing forces against the conductive structures in the feed probes that are oriented normal to the sidewalls  102  against which the feed probes are pressed). Dielectric substrate  70  may be molded over dielectric resonating elements  68 L and  68 H and biasing structures  218  (e.g., to form a single integrated antenna package that is then surface-mounted to substrate  72 ). Dielectric substrate  70  may, if desired, include openings that expose biasing structures  218 . Dielectric substrate  70  may also include openings (holes)  219  that are laterally interposed between each pair of adjacent dielectric resonating elements in phased antenna array  54 . Openings  219  may, for example, serve to further increase isolation between the antennas  40 L and  40 H in phased antenna array  54 . 
       FIG.  24    is an exploded view of the antenna module  120  of  FIGS.  22  and  23   . As shown in  FIG.  24   , feed probes  100 V and  100 H and optionally parasitic elements  108  may be pressed against dielectric resonating elements  68 L and  68 H by biasing structures  218 . In scenarios where dielectric resonating elements  68 L and  68 H are fed by only a single feed probe, parasitic elements  108  may be omitted and/or parasitic elements  114 - 1  and  114 - 2  of  FIG.  8    may be used. 
     Biasing structure  218  may be molded over dielectric resonating elements  68 L and  68 H, feed probes  100 H and  100 V, and parasitic elements  108  during a first molding process (e.g., similar to the first molding process associated with arrow  198  of  FIG.  20   ). Alignment posts may press feed probes  100 H and  100 V and parasitic elements  108  against the dielectric resonating elements during the first molding process and may leave behind alignment post openings in biasing structures  218  after molding. Biasing structures  218  may press feed probes  100 H and  100 V and parasitic elements  108  against dielectric resonating elements  68 L and  68 H to maintain a reliable coupling between the feed probes, parasitic elements, and the dielectric resonating elements. Dielectric substrate  70  may be molded over all of the dielectric resonating elements  68 H and  68 L and biasing structures  218  in a second molding process (e.g., similar to the second molding process associated with arrow  204  of  FIG.  20   ). The assembled phased antenna array  54  may subsequently be surface-mounted to substrate  72  of  FIGS.  22  and  23    to form antenna module  120 . 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20200702
Publication Date: 20230711
Grant Date: 20230711
Priority Date: 20200702
Inventors: RAJAGOPALAN, HARISH
AVSER, BILGEHAN
Garrido Lopez, David
HASNAT, FORHAD
PASCOLINI, MATTIA
ASKARIAN AMIRI, MIKAL
GOMEZ ANGULO, RODNEY A.
YANG, THOMAS W.
WU, JIECHEN
NYLAND, ERIC N.
PAULOTTO, Simone
EDWARDS, JENNIFER M.
HILL, MATTHEW D.
CHOWDHURY, IHTESHAM H.
HURRELL, DAVID A.
YONG, Siwen
WU, JIANGFENG
WAGMAN, Daniel C.
AKBARZADEH, SOROUSH
SCRITZKY, ROBERT
RAMALINGAM, SUBRAMANIAN
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q1/2283", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01R31/2822", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q13/24", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B3/52", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04B3/54", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/0485", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q9/0485", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q9/0485", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04B3/52", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q21/06", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q21/061", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01Q21/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/2225", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01R31/2822", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/2283", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q13/24", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B3/54", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 79010708