Patent Publication Number: US-10763566-B2

Title: Millimeter wave transmission line structures

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with wireless communications circuitry. 
     Electronic devices often include wireless communications 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. Performing millimeter wave communications often involves the use of multiple antennas arranged in a phased antenna array. Each of the antennas in the phased antenna array is coupled to a corresponding transmission line. Operation at these frequencies supports high data rates but may raise significant challenges. For example, millimeter wave communications are often line-of-sight communications and can be characterized by substantial attenuation during signal propagation. In addition, it can be challenging to electromagnetically isolate the transmission lines coupled to each antenna in a phased antenna array at millimeter wave frequencies. 
     It would therefore be desirable to be able to provide electronic devices with improved wireless communications circuitry such as communications circuitry that supports communications at frequencies greater than 10 GHz. 
     SUMMARY 
     An electronic device may be provided with wireless circuitry. The wireless circuitry may include one or more antennas and transceiver circuitry such as millimeter wave transceiver circuitry. The millimeter wave transceiver circuitry and the antennas may be formed on a dielectric substrate having stacked dielectric layers. 
     A first antenna may include a first patch antenna resonating element formed at a first side of the substrate. A second antenna may include a second patch antenna resonating element formed at a second side of the substrate. Transmission lines such as coplanar waveguides may be used to convey signals in frequency bands between 10 GHz and 300 GHz such as millimeter wave signals between the transceiver circuitry and the first and second antennas. 
     For example, a first coplanar waveguide may be formed from a first layer of conductive traces between the first and second patch antenna resonating elements. A second coplanar waveguide may be formed from a second layer of conductive traces between the first and second patch antenna resonating elements. The first coplanar waveguide may be interposed between the second coplanar waveguide and the second antenna resonating element. The second coplanar waveguide may be interposed between the first coplanar waveguide and the first antenna resonating element. 
     The first coplanar waveguide may include a first signal conductor coupled between a first port of the millimeter wave transceiver circuitry and a first antenna feed terminal on the first patch antenna resonating element. The first coplanar waveguide may be coupled to the first patch antenna resonating element through an opening in the second coplanar waveguide. The second coplanar waveguide may include a second signal conductor coupled between a second port of the millimeter wave transceiver circuitry and a second antenna feed terminal on the second patch antenna resonating element. The second coplanar waveguide may be coupled to the second antenna resonating element through an opening in the first coplanar wave guide. The ground conductors in the first coplanar waveguide may be shorted to the ground conductors in the second coplanar waveguide. Additional coplanar waveguides may be formed from the first and second layers of conductive traces for conveying millimeter wave signals for any desired number of antenna feeds and any desired number of antennas in the device. 
     In another suitable arrangement, both the first and second antennas may be formed at a single side of the dielectric substrate. In this scenario, the first and second coplanar waveguides may be formed from a single layer of conductive traces interposed between an antenna ground plane and the first and second patch antenna resonating elements. The conductive traces may include first, second, and third ground conductors. The first signal conductor may be interposed between the first and second ground conductors whereas the second signal conductor is interposed between the second and third ground conductors. 
     The ground conductors in the first and second coplanar waveguides may serve as antenna ground planes for the antennas on one or both sides of the dielectric substrate. At the same time, the ground conductors may serve to isolate the first and second signal conductors to maximize electromagnetic decoupling between the first and second coplanar waveguides (e.g., to maximize isolation between the first and second transceiver ports). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device with wireless communications circuitry in accordance with an embodiment. 
         FIG. 2  is a schematic diagram of an illustrative electronic device with wireless communications circuitry in accordance with an embodiment. 
         FIG. 3  is a rear perspective view of an illustrative electronic device showing illustrative locations at which antennas for communications at frequencies greater than 10 GHz may be located in accordance with an embodiment. 
         FIG. 4  is a diagram of an illustrative transceiver circuit and antenna in accordance with an embodiment. 
         FIG. 5  is a perspective view of an illustrative patch antenna in accordance with an embodiment. 
         FIG. 6  is a perspective view of an illustrative patch antenna with dual ports in accordance with an embodiment. 
         FIG. 7  is a perspective view of an illustrative integrated antenna module in accordance with an embodiment. 
         FIG. 8  is a cross-sectional side view of an illustrative integrated antenna module having antenna resonating elements at a first side of a stacked dielectric substrate in accordance with an embodiment. 
         FIG. 9  is a perspective view of illustrative transmission line structures that may be used to convey millimeter wave signals for an integrated antenna module of the type shown in  FIG. 8  in accordance with an embodiment. 
         FIG. 10  is a cross-sectional side view of an illustrative integrated antenna module having antenna resonating elements at first and second sides of a stacked dielectric substrate in accordance with an embodiment. 
         FIG. 11  is a perspective view of illustrative transmission line structures that may be used to convey millimeter wave signals for an integrated antenna module of the type shown in  FIG. 10  in accordance with an embodiment. 
         FIG. 12  is a top-down view of an illustrative transceiver having alternating signal and ground ports in accordance with an embodiment. 
     
    
    
     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 handling millimeter wave and centimeter wave communications. Millimeter wave and centimeter wave communications, which are sometimes referred to as extremely high frequency (EHF) communications, involve signals at 60 GHz or other frequencies between about 30 GHz and 300 GHz. Centimeter wave communications involve signals at frequencies between about 10 GHz and 30 GHz. If desired, device  10  may also contain wireless communications circuitry 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 computing device such as a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wristwatch device, a pendant device, a headphone or earpiece device, a virtual or augmented reality headset device, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other wearable or miniature device, a television, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, a wireless access point or base station, a desktop computer, a keyboard, a gaming controller, a computer mouse, a mousepad, a trackpad or touchpad, equipment that implements the functionality of two or more of these devices, or other electronic equipment. In the illustrative configuration of  FIG. 1 , device  10  is a portable device such as a cellular telephone, media player, tablet computer, or other portable computing device. Other configurations may be used for device  10  if desired. The example of  FIG. 1  is merely illustrative. 
     As shown in  FIG. 1 , device  10  may include a display such as display  14 . Display  14  may be mounted in a housing such as housing  12 . Housing  12 , which may sometimes be referred to as an enclosure or case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of any two or more of these materials. Housing  12  may be formed using a unibody configuration in which some or all of housing  12  is machined or molded as a single structure or may be formed using multiple structures (e.g., an internal frame structure, one or more structures that form exterior housing surfaces, etc.). 
     Display  14  may be a touch screen display that incorporates a layer of conductive capacitive touch sensor electrodes or other touch sensor components (e.g., resistive touch sensor components, acoustic touch sensor components, force-based touch sensor components, light-based touch sensor components, etc.) or may be a display that is not touch-sensitive. Capacitive touch screen electrodes may be formed from an array of indium tin oxide pads or other transparent conductive structures. 
     Display  14  may include an array of display pixels formed from liquid crystal display (LCD) components, an array of electrophoretic display pixels, an array of plasma display pixels, an array of organic light-emitting diode display pixels, an array of electrowetting display pixels, or display pixels based on other display technologies. 
     Display  14  may be protected using a display cover layer such as a layer of transparent glass, clear plastic, sapphire, or other transparent dielectric. Openings may be formed in the display cover layer. For example, openings may be formed in the display cover layer to accommodate one or more buttons, sensor circuitry such as a fingerprint sensor or light sensor, ports such as a speaker port or microphone port, etc. Openings may be formed in housing  12  to form communications ports (e.g., an audio jack port, a digital data port, charging port, etc.). Openings in housing  12  may also be formed for audio components such as a speaker and/or a microphone. 
     Antennas may be mounted in housing  12 . If desired, some of the antennas (e.g., antenna arrays that may implement beam steering, etc.) may be mounted under an inactive border region of display  14  (see, e.g., illustrative antenna locations  50  of  FIG. 1 ). Display  14  may contain an active area with an array of pixels (e.g., a central rectangular portion). Inactive areas of display  14  are free of pixels and may form borders for the active area. If desired, antennas may also operate through dielectric-filled openings in the rear of housing  12  or elsewhere in device  10 . 
     To avoid disrupting communications when an external object such as a human hand or other body part of a user blocks one or more antennas, antennas may be mounted at multiple locations in housing  12 . Sensor data such as proximity sensor data, real-time antenna impedance measurements, signal quality measurements such as received signal strength information, and other data may be used in determining when one or more antennas is being adversely affected due to the orientation of housing  12 , blockage by a user&#39;s hand or other external object, or other environmental factors. Device  10  can then switch one or more replacement antennas into use in place of the antennas that are being adversely affected. 
     Antennas may be mounted at the corners of housing  12  (e.g., in corner locations  50  of  FIG. 1  and/or in corner locations on the rear of housing  12 ), along the peripheral edges of housing  12 , on the rear of housing  12 , under the display cover glass or other dielectric display cover layer that is used in covering and protecting display  14  on the front of device  10 , under a dielectric window on a rear face of housing  12  or the edge of housing  12 , or elsewhere in device  10 . 
     A schematic diagram showing illustrative components that may be used in device  10  is shown in  FIG. 2 . As shown in  FIG. 2 , device  10  may include storage and processing circuitry such as control circuitry  14 . Control circuitry  14  may include storage such as 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. Processing circuitry in control circuitry  14  may be used to control the operation of device  10 . This processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processor integrated circuits, application specific integrated circuits, etc. 
     Control circuitry  14  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  14  may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry  14  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, etc. 
     Device  10  may include input-output circuitry  16 . Input-output circuitry  16  may include input-output devices  18 . Input-output devices  18  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  18  may include user interface devices, data port devices, 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, 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  16  may include wireless communications circuitry  34  for communicating wirelessly with external equipment. Wireless communications circuitry  34  may include radio-frequency (RF) transceiver circuitry formed from one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive RF components, one or more antennas  40 , transmission lines, and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). 
     Wireless communications circuitry  34  may include transceiver circuitry  20  for handling various radio-frequency communications bands. For example, circuitry  34  may include transceiver circuitry  22 ,  24 ,  26 , and  28 . 
     Transceiver circuitry  24  may be wireless local area network (WLAN) transceiver circuitry. Transceiver circuitry  24  may handle 2.4 GHz and 5 GHz bands for WiFi® (IEEE 802.11) communications and may handle the 2.4 GHz Bluetooth® communications band. 
     Circuitry  34  may use cellular telephone transceiver circuitry  26  for handling wireless communications in frequency ranges such as a communications band from 700 to 960 MHz, a communications band from 1710 to 2170 MHz, and a communications from 2300 to 2700 MHz or other communications bands between 700 MHz and 4000 MHz or other suitable frequencies (as examples). Circuitry  26  may handle voice data and non-voice data. 
     Millimeter wave transceiver circuitry  28  (sometimes referred to as extremely high frequency transceiver circuitry  28  or transceiver circuitry  28 ) may support communications at frequencies between about 10 GHz and 300 GHz. For example, transceiver circuitry  28  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, transceiver circuitry  28  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, circuitry  28  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. If desired, circuitry  28  may support communications at multiple frequency bands between 10 GHz and 300 GHz such as a first band from 27.5 GHz to 28.5 GHz, a second band from 37 GHz to 41 GHz, and a third band from 57 GHz to 71 GHz, or other communications bands between 10 GHz and 300 GHz. Circuitry  28  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.). While circuitry  28  is sometimes referred to herein as millimeter wave transceiver circuitry  28 , millimeter wave transceiver circuitry  28  may handle communications at any desired communications bands at frequencies between 10 GHz and 300 GHz (e.g., in millimeter wave communications bands, centimeter wave communications bands, etc.). 
     Wireless communications circuitry  34  may include satellite navigation system circuitry such as Global Positioning System (GPS) receiver circuitry  22  for receiving GPS signals at 1575 MHz or for handling other satellite positioning data (e.g., GLONASS signals at 1609 MHz). Satellite navigation system signals for receiver  22  are received from a constellation of satellites orbiting the earth. 
     In satellite navigation system links, cellular telephone links, and other long-range links, wireless signals are typically used to convey data over thousands of feet or miles. In WiFi® and Bluetooth® links at 2.4 and 5 GHz and other short-range wireless links, wireless signals are typically used to convey data over tens or hundreds of feet. Extremely high frequency (EHF) wireless transceiver circuitry  28  may convey signals over these short distances that travel between transmitter and receiver 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 is 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. 
     Wireless communications circuitry  34  can include circuitry for other short-range and long-range wireless links if desired. For example, wireless communications circuitry  34  may include circuitry for receiving television and radio signals, paging system transceivers, near field communications (NFC) circuitry, etc. 
     Antennas  40  in wireless communications circuitry  34  may be formed using any suitable antenna types. For example, antennas  40  may include antennas with resonating elements that are formed from 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. 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 local wireless link antenna and another type of antenna may be used in forming a remote wireless link antenna. Dedicated antennas may be used for receiving satellite navigation system signals or, if desired, antennas  40  can be configured to receive both satellite navigation system signals and signals for other communications bands (e.g., wireless local area network signals and/or cellular telephone signals). Antennas  40  may include one or more antennas such as antennas arranged in one or more phased antenna arrays for handling millimeter and centimeter wave communications. 
     Transmission line paths may be used to route antenna signals within device  10 . For example, transmission line paths may be used to couple antenna structures  40  to transceiver circuitry  20 . Transmission lines in device  10  may include coaxial cable paths, microstrip transmission lines, stripline transmission lines, edge-coupled microstrip transmission lines, edge-coupled stripline transmission lines, waveguide structures, coplanar waveguides, grounded coplanar waveguides, transmission lines formed from combinations of transmission lines of these types, etc. Filter circuitry, switching circuitry, impedance matching circuitry, and other circuitry may be interposed within the transmission lines, if desired. 
     In devices such as handheld devices, the presence of an external object such as the hand of a user or a table or other surface on which a device is resting has a potential to block wireless signals such as millimeter wave signals. Accordingly, it may be desirable to incorporate multiple antennas or phased antenna arrays into device  10 , each of which is placed in a different location within device  10 . With this type of arrangement, an unblocked antenna or phased antenna array may be switched into use. In scenarios where a phased antenna array is formed in device  10 , once switched into use, the phased antenna array may use beam steering to optimize wireless performance. Configurations in which antennas from one or more different locations in device  10  are operated together may also be used. 
       FIG. 3  is a perspective view of electronic device  10  showing illustrative locations  50  on the rear of housing  12  in which antennas  40  (e.g., single antennas and/or phased antenna arrays for use with wireless circuitry  34  such as transceiver circuitry  28 ) may be mounted in device  10 . Antennas  40  may be mounted at the corners of device  10 , along the edges of housing  12  such as edge  12 E, on upper and lower portions of rear housing portion (wall)  12 R, in the center of rear housing wall  12 R (e.g., under a dielectric window structure or other antenna window in the center of rear housing  12 R), at the corners of rear housing wall  12 R (e.g., on the upper left corner, upper right corner, lower left corner, and lower right corner of the rear of housing  12  and device  10 ), etc. 
     In configurations in which housing  12  is formed entirely or nearly entirely from a dielectric, antennas  40  may transmit and receive antenna signals through any suitable portion of the dielectric. In configurations in which housing  12  is formed from a conductive material such as metal, regions of the housing such as slots or other openings in the metal may be filled with plastic or other dielectric. Antennas  40  may be mounted in alignment with the dielectric in the openings. These openings, which may sometimes be referred to as dielectric antenna windows, dielectric gaps, dielectric-filled openings, dielectric-filled slots, elongated dielectric opening regions, etc., may allow antenna signals to be transmitted to external equipment from antennas  40  mounted within the interior of device  10  and may allow internal antennas  40  to receive antenna signals from external equipment. In another suitable arrangement, antennas  40  may be mounted on the exterior of conductive portions of housing  12 . 
     In devices with phased antenna arrays, circuitry  34  may include gain and phase adjustment circuitry that is used in adjusting the signals associated with each antenna  40  in an array (e.g., to perform beam steering). Switching circuitry may be used to switch desired antennas  40  into and out of use. If desired, each of locations  50  may include multiple antennas  40  (e.g., a set of three antennas or more than three or fewer than three antennas in a phased antenna array) and, if desired, one or more antennas from one of locations  50  may be used in transmitting and receiving signals while using one or more antennas from another of locations  50  in transmitting and receiving signals. 
     A schematic diagram of a millimeter wave antenna or other antenna  40  coupled to transceiver circuitry  20  (e.g., transceiver circuitry  28  and/or other transceiver circuitry  20 ) is shown in  FIG. 4 . As shown in  FIG. 4 , radio-frequency transceiver circuitry  20  may be coupled to antenna feed  100  of antenna  40  using transmission line  64 . Antenna feed  100  may include a positive antenna feed terminal such as positive antenna feed terminal  96  and may include a ground antenna feed terminal such as ground antenna feed terminal  98 . Transmission line  64  may be formed form metal traces on a printed circuit or other conductive structures and may have a positive transmission line signal path such as path  91  that is coupled to terminal  96  and a ground transmission line signal path such as path  94  that is coupled to terminal  98 . Transmission line paths such as path  64  may be used to route antenna signals within device  10 . For example, transmission line paths may be used to couple antenna structures such as one or more antennas in an array of antennas to transceiver circuitry  20 . Transmission lines in device  10  may include coaxial cable paths, microstrip transmission lines, stripline transmission lines, edge-coupled microstrip transmission lines, edge-coupled stripline transmission lines, waveguide structures, coplanar waveguides, grounded coplanar waveguides, transmission lines formed from combinations of transmission lines of these types, etc. Filter circuitry, switching circuitry, impedance matching circuitry, and other circuitry may be interposed within transmission line  64  and/or circuits such as these may be incorporated into antenna  40  if desired (e.g., to support antenna tuning, to support operation in desired frequency bands, etc.). 
     Device  10  may contain multiple antennas  40 . The antennas may be used together or one of the antennas may be switched into use while other antenna(s) are switched out of use. If desired, control circuitry  14  may be used to select an optimum antenna to use in device  10  in real time and/or to select an optimum setting for adjustable wireless circuitry associated with one or more of antennas  40 . Antenna adjustments may be made to tune antennas to perform in desired frequency ranges, to perform beam steering with a phased antenna array, and to otherwise optimize antenna performance. Sensors may be incorporated into antennas  40  to gather sensor data in real time that is used in adjusting antennas  40 . 
     In some configurations, antennas  40  may be arranged in one or more antenna arrays (e.g., phased antenna arrays to implement beam steering functions). For example, the antennas that are used in handling millimeter and centimeter wave signals for transceiver circuits  28  may be implemented as phased antenna arrays. The radiating elements in a phased antenna array for supporting millimeter and centimeter wave communications may be patch antennas, dipole antennas, dipole antennas with directors and reflectors in addition to dipole antenna resonating elements (sometimes referred to as Yagi antennas or beam antennas), or other suitable antenna elements. Transceiver circuitry can be integrated with the phased antenna arrays to form integrated phased antenna array and transceiver circuit modules (sometimes referred to herein as integrated antenna modules or integrated antenna and transceiver modules). 
     An illustrative patch antenna that may be used in conveying signals at frequencies greater than 10 GHz such as millimeter wave signals is shown in  FIG. 5 . As shown in  FIG. 5 , patch antenna  40  may have a patch antenna resonating element  104  that is separated from and parallel to a ground plane such as antenna ground plane  92 . Positive antenna feed terminal  96  may be coupled to patch antenna resonating element  104 . Ground antenna feed terminal  98  may be coupled to ground plane  92 . If desired, conductive path  88  may be used to couple terminal  96 ′ to terminal  96  so that antenna  40  is fed using a transmission line with a positive conductor coupled to terminal  96 ′ and thus terminal  96 . If desired, path  88  may be omitted. Other types of antenna feed arrangements may be used if desired. The illustrative feeding configuration of  FIG. 5  is merely illustrative. 
     As shown in  FIG. 5 , patch antenna resonating element  104  may lie within a plane such as the X-Y plane of  FIG. 5  (e.g., the lateral surface area of element  104  may lie in the X-Y plane). Patch antenna resonating element  104  may sometimes be referred to herein as patch  104 , patch element  104 , patch resonating element  104 , antenna resonating element  104 , or resonating element  104 . Ground  92  may lie within a plane that is parallel to the plane of patch  104 . Patch  104  and ground  92  may therefore lie in separate parallel planes that are separated by a distance H. Patch  104  and ground  92  may be formed from conductive traces patterned on a dielectric substrate such as a rigid or flexible printed circuit board substrate, metal foil, stamped sheet metal, electronic device housing structures, or any other desired conductive structures. The length of the sides of patch  104  may be selected so that antenna  40  resonates at a desired operating frequency. For example, the sides of element  104  may each have a length L 0  that is approximately equal to half of the wavelength (e.g., within 15% of half of the wavelength) of the signals conveyed by antenna  40  (e.g., in scenarios where patch element  104  is substantially square). 
     If desired, antenna  40  may include a parasitic antenna resonating element such as parasitic antenna resonating element  106 . Parasitic antenna resonating element  106  may have a lateral surface area extending in the X-Y plane of  FIG. 5  and may be separated from patch element  104  by distance H′. Parasitic antenna resonating element  106  may have any desired shape (e.g., a rectangular shape, square shape, polygonal shape, or other shapes having curved and/or straight edges). If desired, parasitic antenna resonating element  106  may have a cross-shape in which element  106  includes three or more conductive arms extending from a common point along at least two different non-parallel longitudinal axes. Parasitic antenna resonating element  106  may be formed from conductive traces patterned onto a dielectric substrate, from stamped sheet metal, metal foil, electronic device housing structures, or any other desired conductive structures. Parasitic antenna resonating element  106  may sometimes be referred to herein as parasitic resonating element  106 , parasitic antenna element  106 , parasitic element  106 , parasitic patch  106 , parasitic conductor  106 , parasitic structure  106 , patch  106 , or parasitic  106 . Parasitic element  106  may have edges that are aligned with (e.g., extend parallel to) one or more sides of patch  104  or may be rotated with respect to patch  104  if desired. 
     Parasitic element  106  is not directly fed (e.g., element  106  is not electrically connected to any transmission lines  64 ), whereas patch antenna resonating element  104  is directly fed via transmission line  64  and feed terminal  96 . Parasitic element  106  may create a constructive perturbation of the electromagnetic field generated by patch antenna resonating element  104 , creating a new resonance for antenna  40 . This may serve to broaden the overall bandwidth of antenna  40  (e.g., to cover an entire millimeter wave frequency band from 57 GHz to 71 GHz). 
     The example of  FIG. 5  is merely illustrative. Patch  104  may have a square shape in which all of the sides of patch  104  are the same length or may have a different rectangular shape. If desired, patch  104  and ground  92  may have different shapes and orientations (e.g., planar shapes, curved patch shapes, patch shapes with non-rectangular outlines, shapes with straight edges such as squares, shapes with curved edges such as ovals and circles, shapes with combinations of curved and straight edges, etc.). In scenarios where patch  104  is non-rectangular, patch  104  may have a side or a maximum lateral dimension that is approximately equal to (e.g., within 15% of) half of the wavelength of operation, for example. If desired, parasitic element  106  may be omitted. 
     To enhance the polarizations handled by patch antenna  40 , antenna  40  may be provided with multiple feeds. An illustrative patch antenna with multiple feeds is shown in  FIG. 6 . As shown in  FIG. 6 , antenna  40  may have a first feed at antenna port P 1  that is coupled to transmission line  64 - 1  and a second feed at antenna port P 2  that is coupled to transmission line  64 - 2 . The first antenna feed may have a first ground feed terminal coupled to ground  92  and a first positive feed terminal  96 -P 1  coupled to patch  104 . The second antenna feed may have a second ground feed terminal coupled to ground  92  and a second positive feed terminal  96 -P 2  on patch  104 . 
     Patch  104  may have a rectangular shape with a first pair of edges running parallel to dimension Y and a second pair of perpendicular edges running parallel to dimension X, for example. The length of patch  104  in dimension Y is L 1  and the length of patch  104  in dimension X is L 2 . With this configuration, antenna  40  may be characterized by orthogonal polarizations. 
     When using the first antenna feed associated with port P 1 , antenna  40  may transmit and/or receive antenna signals in a first communications band at a first frequency (e.g., a frequency at which one-half of the corresponding wavelength is approximately equal to dimension L 1 ). These signals may have a first polarization (e.g., the electric field E 1  of antenna signals  102  associated with port P 1  may be oriented parallel to dimension Y). When using the antenna feed associated with port P 2 , antenna  40  may transmit and/or receive antenna signals in a second communications band at a second frequency (e.g., a frequency at which one-half of the corresponding wavelength is approximately equal to dimension L 2 ). These signals may have a second polarization (e.g., the electric field E 2  of antenna signals  102  associated with port P 2  may be oriented parallel to dimension X so that the polarizations associated with ports P 1  and P 2  are orthogonal to each other). In scenarios where patch  104  is square (e.g., length L 1  is equal to length L 2 ), ports P 1  and P 2  may cover the same communications band. In scenarios where patch  104  is rectangular, ports P 1  and P 2  may cover different communications bands if desired. During wireless communications using device  10 , device  10  may use port P 1 , port P 2 , or both port P 1  and P 2  to transmit and/or receive signals (e.g., millimeter wave signals). 
     The example of  FIG. 6  is merely illustrative. Patch  104  may have a square shape in which all of the sides of patch  104  are the same length or may have a rectangular shape in which length L 1  is different from length L 2 . In general, patch  104  and ground  92  may have different shapes and orientations (e.g., planar shapes, curved patch shapes, patch element shapes with non-rectangular outlines, shapes with straight edges such as squares, shapes with curved edges such as ovals and circles, shapes with combinations of curved and straight edges, etc.). If desired, the dual-polarization patch antenna as shown in  FIG. 6  may be provided with a parasitic antenna resonating element such as element  106  of  FIG. 5  (e.g., to widen the bandwidth of antenna  40 ). 
     Antennas  40  such as single-polarization patch antennas of the type shown in  FIG. 5  and/or dual-polarization patch antennas of the type shown in  FIG. 6  may be arranged within a corresponding phased antenna array in device  10 . If desired, one or more antennas  40  may be integrated with other circuitry such as transceiver circuitry  20  to form an integrated antenna module. 
       FIG. 7  is a perspective view of an illustrative integrated antenna module for handling signals at frequencies greater than 10 GHz in device  10  (e.g., millimeter wave signals). As shown in  FIG. 7 , device  10  may be provided with an integrated antenna module such as module  109 . Module  109  may include one or more antennas  40  (e.g., single-polarization patch antennas of the type shown in  FIG. 5  and/or dual-polarization patch antennas of the type shown in  FIG. 6 ) formed on a dielectric substrate such as dielectric substrate  120 . Substrate  120  may be, for example, a rigid or printed circuit board or other dielectric substrate. Substrate  120  may be a stacked dielectric substrate that includes multiple stacked dielectric layers  122  (e.g., multiple layers of printed circuit board substrate such as multiple layers of fiberglass-filled epoxy, rigid printed circuit board material, flexible printed circuit board material, ceramic, plastic, glass, or other dielectrics). 
     Any desired number of antennas  40  may be formed on substrate  120  (e.g., one antenna  40 , two or more antennas  40  arranged in one or more phased antenna arrays, etc.). Antennas  40  may be formed adjacent to front side  112  and/or rear side  114  of substrate  120  (e.g., at the surface of substrate  120  or embedded within layers  122  adjacent to sides  112  or  114 ). There may be, for example, a square array of four elements  40  at front side  112  of substrate  120  and/or a square array of four elements  40  at rear side  114  of substrate  120 . The antennas  40  at front side  112  may, for example, form a first phased antenna array whereas the antennas  40  at rear side  114  may, for example, form a second phased antenna array. 
     The use of a phased array of elements  40  allows the signals of antennas  40  to be steered using beam steering techniques. This is merely illustrative. In general, one or more antennas  40  may be formed on one or both of sides  112  and  114  and may be arranged in any desired pattern (e.g., antennas  40  need not be arranged in a phased antenna array). Antennas  40  may include elements such as patch antenna resonating elements  104 , antenna ground plane elements  92 , and/or parasitic antenna resonating elements  106  that are interposed between or formed on layers  122  of substrate  120 . One or more electrical components  110  (e.g., transceiver circuitry such as circuitry  20 , circuitry  28 , etc.) may be mounted on substrate  120  (e.g., on rear surface  114 ). Components  110  may be mounted to the same layer  122  as one or more antennas  40  or may be mounted to other layers  122  in substrate  120 . Components  110  may be mounted to the surface of substrate  120  at side  114 , for example. Components  110  may, for example, include integrated circuits (e.g., integrated circuit chips) or integrated circuit packages mounted to substrate  120 . Components  110  may sometimes be referred to herein as transceivers  110 , transceiver circuitry  110 , or transceiver chips  110 . If desired, components  110  may include control circuitry (e.g., some or all of circuitry  14  of  FIG. 2 ) or any other desired electrical components. 
     The example of  FIG. 7  is merely illustrative. In general, any desired number of antennas  40  may be formed adjacent to sides  112  and/or  114  or at other locations within the layers  122  of substrate  120 . For example, zero, one, two, or more than two antennas  40  may be formed adjacent to front side  112 . Similarly, zero, one, two, or more than two antennas  40  may be formed adjacent to rear side  114 . Substrate  120  may have any desired shape and may be flexible, rigid, or may include flexible and rigid portions. 
     Conductive traces or other metal layers that are used in forming transmission line structures such as transmission lines  64  of  FIG. 4  may be interposed between layers  122  of substrate  120 . The transmission lines may be used to convey signals at frequencies greater than 10 GHz such as millimeter wave signals between transceiver  110  and antennas  40 . For example, a respective transmission line may be coupled between each antenna  40  in module  109  and one or more transceivers  110 . In scenarios where antennas  40  include multiple feeds (e.g., as shown in  FIG. 6 ), a respective transmission line may be coupled between each antenna feed in module  109  and transceivers  110 . As the number of antennas  40  and antenna feeds  100  implemented in module  109  increases, the routing complexity of the corresponding transmission lines may increase. If care is not taken, it can be difficult to ensure that each of the transmission lines in module  109  is sufficiently isolated from the other transmission lines in module  109 . 
       FIG. 8  is a cross-sectional side view of integrated antenna module  109  (e.g., as taken in the Y-Z plane of  FIG. 7 ) having antennas  40  formed adjacent to a single side of module  109 . As shown in  FIG. 8 , integrated antenna module  109  may include multiple antennas such as a first antenna  40 - 1  and a second antenna  40 - 2  adjacent to side  112  of module  109 . Substrate  120  may include multiple dielectric layers such as a first layer  122 - 1 , a second layer  122 - 2  over the first layer, a third layer  122 - 3  over the second layer, a fourth layer  122 - 4  over the third layer, and a fifth layer  122 - 5  over the fourth layer. Additional dielectric layers  122  may be stacked within substrate  120  if desired. 
     With this type of arrangement, antennas  40 - 1  and  40 - 2  may be embedded within the layers of substrate  120 . For example, first antenna  40 - 1  may include a first antenna resonating element  104 - 1  formed on layer  122 - 4  and second antenna  40 - 2  may include a second antenna resonating element  104 - 2  formed on layer  122 - 4 . If desired, antenna  40 - 1  may include a parasitic element  106  such as parasitic  106 - 1  formed on layer  122 - 5  and antenna  40 - 2  may include a parasitic element  106  such as parasitic  106 - 2  formed on layer  122 - 5 . 
     Grounded conductive traces  130  may be formed on layer  122 - 1 . Grounded conductive traces  130  may form antenna ground plane  92  for antennas  40 - 1  and  40 - 2  (e.g., resonating elements  104 - 1  and  104 - 2  may be formed at distance H from traces  130  as shown in  FIGS. 5 and 6 ). A transceiver  110  may be formed at side  114  of substrate  120 . Transceiver  110  may include, for example, an integrated circuit or integrated circuit package mounted to side  114  of substrate  120 . Transceiver  110  may include transceiver ports  134  such as a first port  134 - 1  and a second port  134 - 2 . Each port  134  may be used to convey signals (e.g., millimeter wave signals) for a corresponding antenna  40 . Ports  134  may include conductive contact pads, solder balls, microbumps, conductive pins, conductive pillars, conductive sockets, conductive clips, welds, conductive adhesive, conductive wires, interface circuits, or any other desired conductive interconnect structures. 
     Conductive traces  136  may be formed on dielectric layer  122 - 2 . Conductive traces  136  and conductive traces  130  may form transmission line structures  137  for antennas  40  (e.g., one or more transmission lines  64  as shown in  FIG. 4 ). Transmission line structures  137  may, for example, included coplanar waveguide structures for conveying millimeter wave signals between transceiver ports  134  and antennas  40 . 
     Conductive traces  136  may include signal portions (sometimes referred to herein as signal conductors) and grounded portions (sometimes referred to herein as ground conductors). Each signal conductor in traces  136  may be coupled to a corresponding feed terminal  96  on antennas  40  via a corresponding vertical conductive structure  138  (e.g., traces  136  may include at least one signal conductor for each antenna  40  formed on module  109 ). Each signal conductor in traces  136  may be coupled to a respective port  134  on transceiver  110  via a corresponding vertical conductive structure  128 . Vertical conductive structures  138  and  128  may include conductive through-vias, metal pillars, metal wires, conductive pins, or any other desired vertical conductive interconnects. One or more holes or openings  132  may be formed in ground traces  130  for accommodating vertical conductors  128 . 
     The ground conductors within traces  136  may be laterally interposed (e.g., in the X-Y plane) between the signal conductors and may serve to electromagnetically isolate each signal conductor from the other signal conductors in traces  136 . The signal and ground conductors in traces  136  may, for example, be configured to form coplanar waveguide transmission lines for each antenna  40 . If desired, the ground conductors in traces  136  may be shorted to ground traces  130 . In this scenario, the signal and ground conductors in traces  136  and ground traces  130  may be configured to form grounded coplanar waveguide transmission lines for each antenna  130 . 
     In the example of  FIG. 8 , traces  136  may include a first signal conductor coupled to port  134 - 1  over vertical conductive structure  132 - 1 . The first signal conductor may be coupled to feed terminal  96 - 1  on antenna resonating element  104 - 1  of antenna  40 - 1  over vertical conductive structure  138 - 1 . Vertical conductor  132 - 1  may extend from traces  136  through layer  122 - 2 , opening  132 - 1  in ground traces  130 , and layer  122 - 1  to first port  134 - 1 . Vertical conductor  138 - 1  may extend from traces  136  through layers  122 - 3  and  122 - 4  to feed terminal  96 - 1 . 
     Similarly, traces  136  may include a second signal conductor coupled to port  134 - 2  over vertical conductive structure  132 - 2 . The second signal conductor may be coupled to feed terminal  96 - 2  on antenna resonating element  104 - 2  of antenna  40 - 2  over vertical conductive structure  138 - 2 . Vertical conductor  132 - 2  may extend from traces  136  through layer  122 - 2 , opening  132 - 1  in ground traces  130 , and layer  122 - 1  to second port  134 - 2 . Vertical conductor  138 - 2  may extend from traces  136  through layers  122 - 3  and  122 - 4  to feed terminal  96 - 2 . The first and second signal conductors in traces  136  may each be laterally interposed between two corresponding ground conductors in traces  136  that serve to isolate the signal conductors from each other. 
     When configured in this way, the first signal conductor and two of the ground conductors in traces  136  may form a first transmission line  64  (e.g., a first coplanar waveguide) that conveys signals at frequencies above 10 GHz between port  134 - 1  and antenna  40 - 1  whereas the second signal conductor and two of the ground conductors in traces  136  form a second transmission line (e.g., a second coplanar waveguide) that conveys signals between port  134 - 2  and antenna  40 - 2 . If desired, the ground conductors in traces  136  may be shorted to ground traces  130  to form first and second grounded coplanar wave guide transmission lines for conveying signals between ports  134  and antennas  40 . When configured in this way, antennas  40  adjacent to side  112  of module  109  such as antennas  40 - 1  and  40 - 2  may convey signals over a first hemisphere above side  112  (e.g., as shown by arrow  140 ). Antennas  40 - 1  and  40 - 2  may, for example, be elements in a phased antenna array that performs beam steering over the hemisphere above side  112  of module  109 . 
     The example of  FIG. 8  is merely illustrative. If desired, additional layers  122  may be interposed between resonating elements  104  and parasitic elements  106 , between traces  136  and  130 , and/or between traces  130  and transceiver  110 . Fewer or additional layers  122  may be interposed between resonating elements  104  and traces  136 . One or more additional layers  122  may be formed over parasitic elements  106  and/or under transceiver  110  if desired (e.g., transceiver  110  may be formed within a cavity defined by two layers  122  in substrate  120 ). Parasitic elements  106  may be omitted if desired. Antenna resonating elements  104  may all be formed on the same dielectric layer (e.g., layer  122 - 4 ) or two or more resonating elements  104  may be formed on different dielectric layers. In yet another suitable arrangement, substrate  120  may be omitted and antennas  40 - 1  and  40 - 2  may be formed on other substrate structures or may be formed without substrates. 
     The example of  FIG. 8  in which two antennas  40 - 1  and  40 - 2  are formed adjacent to side  112  is merely illustrative. In general, any desired number of antennas  40  may be formed adjacent to side  112  and fed using corresponding coplanar waveguides (e.g., grounded coplanar waveguides) formed from structures  137 . In the example of  FIG. 8 , antennas  40 - 1  and  40 - 2  are each shown as only having a single feed for the sake of simplicity. In order to enhance the polarizations covered by antennas  40 , antennas  40 - 1  and  40 - 2  may include two feeds such as shown in  FIG. 6 . 
     In this scenario, structures  137  may include respective coplanar waveguides (e.g., traces  136  may include respective signal conductors) for each antenna feed terminal  96  that is used. For example, each feed terminal  96  of antenna  40 - 1  may be coupled to a different corresponding signal conductor within traces  136  and to a different corresponding transceiver port  134 . Similarly, each feed terminal  96  of antenna  40 - 2  may be coupled to a different corresponding signal conductor within traces  136  and to a different corresponding transceiver port  134  (e.g., antennas  40 - 1  and  40 - 2  may have a combined total of four antenna feeds that are fed using four respective coplanar waveguides formed using structures  137  and four different transceiver ports  134 ). The ground conductors within traces  136  and ground traces  130  may serve to shield side  114  of module  109  from signals conveyed by antennas  40 - 1  and  40 - 2 . At the same time, the ground conductors within traces  136  and ground traces  130  may serve to isolate each signal conductor in traces  136  from the other signal conductors in traces  136 , thereby minimizing electromagnetic coupling between the signals conveyed by each port  134  of transceiver  110 , for example. 
       FIG. 9  is a perspective view of transmission line structures  137  for antennas  40 - 1  and  40 - 2 . In the example of  FIG. 9 , dielectric layers  122  are not shown for the sake of clarity. As shown in  FIG. 9 , conductive traces  136  may be formed at distance  144  from ground traces  130  (e.g., the thickness of layer  122 - 2  of  FIG. 8  may be equal to distance  144 ). 
     Conductive traces  136  may include grounded portions  136 G that are sometimes referred to herein as ground conductors, ground traces, or ground portions. Conductive traces  136  may include signal-level portions  136 P that are sometimes referred to herein as signal conductors, signal traces, or micro strips. Signal conductors  136 P may be laterally interposed between two ground conductors  136 G. Signal conductors  136 P may be separated from the two adjacent ground conductors  136 G by gaps or openings that are free from conductive material. 
     If desired, ground conductors  136 G may be shorted to ground traces  130  over vertical conductive structures  142 . Vertical conductive structures  142  may include conductive through-vias, metal pillars, metal wires, conductive pins, or any other desired vertical conductive interconnect structures. Ground traces  136 G and  130  may be held at a ground or reference potential, for example. Ground traces  136 G and/or  130  may, if desired, be shorted to one or more dedicated ground ports  134  on transceiver  110  ( FIG. 8 ). 
     Each signal conductor  136 P may be coupled to a respective signal port  134  on transceiver  110  and to a respective antenna feed terminal  96  on a corresponding antenna  40 . In the example of  FIG. 9 , traces  136  include a first signal conductor  136 P- 1  coupled to port  134 - 1  on transceiver  110  over vertical conductor  128 - 1  and coupled to feed terminal  96 - 1  on antenna  40 - 1  over vertical conductor  138 - 1  ( FIG. 8 ). Traces  136  include a second signal conductor  136 P- 2  be coupled to port  134 - 2  over vertical conductor  128 - 2  and coupled to feed terminal  96 - 2  on antenna  40 - 2  over vertical conductor  138 - 2 . 
     Signal conductor  136 P- 1  may convey antenna currents between transceiver port  134 - 1  and feed terminal  96 - 1  on antenna  40 - 1 . Corresponding signals for antenna  40 - 1  may be conveyed down the longitudinal length of signal conductor  136 P- 1  (e.g., along the Y-axis of  FIG. 9 ) between the ground conductors  136 G adjacent to signal conductor  136 P- 1  and the underlying ground traces  130  (e.g., from vertical conductive structure  128 - 1  to vertical conductive structure  138 - 1  as shown in  FIG. 8 ). Similarly, signal conductor  136 P- 2  may convey antenna currents between transceiver port  134 - 2  and feed terminal  96 - 2  on antenna  40 - 2 . Corresponding signals for antenna  40 - 2  may be conveyed down the longitudinal length of signal conductor  136 P- 2  between the ground conductors  136 G adjacent to signal conductor  136 P- 2  and the underlying ground traces  130  (e.g., from vertical conductive structure  128 - 2  to vertical conductive structure  138 - 2  as shown in  FIG. 8 ). 
     In this way, transmission line structures  137  may be configured to include a first coplanar waveguide  137 - 1  formed from signal conductor  136 P- 1 , the adjacent ground traces  136 G, and the underlying ground traces  130  that conveys signals for first antenna  40 - 1  and a second coplanar waveguide  137 - 2  formed from signal conductor  136 P- 2 , the adjacent ground traces  136 G, and the underlying ground traces  130  that conveys signals for second antenna  40 - 2  (e.g., first coplanar waveguide  137 - 1  may form a first transmission line  64  for antenna  40 - 1  having a signal path  91  formed from conductor  136 P- 1  and ground path  94  formed from traces  136 G and  130 , whereas second coplanar waveguide  137 - 2  forms a second transmission line  64  for antenna  40 - 2  having a signal path  91  formed from conductor  136 P- 2  and ground path  94  formed from traces  136 G and  130  as shown in  FIG. 4 ). Transmission lines  137 - 1  and  137 - 2  may sometimes be referred to as grounded coplanar transmission lines in scenarios where vertical conductive structures  142  are formed between traces  136 G and  130 . Structures  142  may be omitted if desired. 
     When configured in this way, ground traces  136 G and  130  may both serve as antenna ground  92  for antennas  40 - 1  and  40 - 2  ( FIGS. 5 and 6 ). Ground traces  136 G may serve to isolate signal conductor  136 P- 1  from the signals conveyed over coplanar waveguide  137 - 2  and to isolate signal conductor  136 P- 2  from the signals conveyed over coplanar waveguide  137 - 1 . In this way, the signals at frequencies greater than 10 GHz such as millimeter wave signals conveyed over coplanar waveguide  137 - 1  may be electromagnetically decoupled from the signals conveyed over coplanar waveguide  137 - 2 , thereby minimizing interference between antenna ports  134 - 1  and  134 - 2  and optimizing the wireless performance of antenna module  109 , for example. 
     The example of  FIG. 9  is merely illustrative. In general, layer  136  may include a different respective signal conductor  136 P for each feed terminal  96  on antennas  40  that is used (e.g., structures  137  may include a different respective coplanar waveguide for each feed terminal that is used). For example, in scenarios where module  109  includes two antennas  40  each having two feeds (e.g., as shown in  FIG. 6 ), traces  136  may include four signal conductors  136 P, each separated from the other signal conductors  136 P by at least one ground trace  136 G. In general, any desired number of antennas  40  having any desired number of feeds may be provided at side  112  of module  109  (e.g., one antenna  40 , two antennas  40 , three antennas  40 , four antennas  40 , between four and eight antennas  40 , between eight and sixteen antennas  40 , more than sixteen antennas  40 , etc.). While the transmission line structures shown in  FIG. 9  may provide suitable electromagnetic decoupling for each antenna  40  when antennas  40  are formed at a single side  112  of substrate  120 , if care is not taken, it can also be challenging to ensure transmission line isolation in scenarios where antennas  40  are formed at both sides of substrate  120 . 
       FIG. 10  is a cross-sectional side view of antenna module  109  having antennas  40  formed adjacent to both sides of substrate  120 . As shown in  FIG. 10 , substrate  120  may include dielectric layers such as first dielectric layer  122 - 1 , second dielectric layer  122 - 2  over the first layer, third dielectric layer  122 - 3  over the second layer, fourth dielectric layer  122 - 4  over the third layer, fifth dielectric layer  122 - 5  over the fourth layer, sixth dielectric layer  122 - 6  over the fifth layer, seventh dielectric layer  122 - 7  over the sixth layer, and eighth dielectric layer  122 - 8  over the seventh dielectric layer. 
     Module  109  may include a first set of antennas  40  adjacent to side  112  and a second set of antennas  40  adjacent to side  114 . In the example of  FIG. 10 , a first antenna  40 - 1  is provided adjacent to side  112  and a second antenna  40 - 2  is provided adjacent to side  114 . Patch antenna resonating element  104 - 1  of antenna  40 - 1  may be formed on dielectric layer  122 - 7 . If desired, antenna  40 - 1  may include a parasitic element  106 - 1  formed on layer  122 - 8 . Patch antenna resonating element  104 - 2  of antenna  40 - 2  may be formed on dielectric layer  122 - 2 . If desired, antenna  40 - 2  may include a parasitic element  106 - 2  formed on layer  122 - 1 . 
     First conductive traces  156  may be formed on a surface of dielectric layer  122 - 5 . Second conductive traces  158  may be formed on a surface of dielectric layer  122 - 4 . Conductive traces  156  and  158  may form transmission line structures  159  (e.g., one or more transmission lines  64  of  FIG. 4 ). Transmission line structures  159  may, for example, include coplanar waveguide structures for both antennas adjacent to side  112  such as antenna  40 - 1  and antennas adjacent to side  114  such as antenna  40 - 2 . 
     First conductive traces  156  may include two or more ground conductors and one or more signal conductors. The signal conductors in traces  156  may be coupled to ports  134  of transceiver  110  over corresponding vertical conductive structures  128  and may be coupled to feed terminals  96  on the antennas  40  adjacent to side  114  over corresponding vertical conductive structures  150 . If desired, the ground conductors in traces  156  may be coupled to corresponding ports  134  of transceiver  110 . 
     Second conductive traces  158  may include two or more ground conductors and one or more signal conductors. The signal conductors in traces  158  may be coupled to ports  134  of transceiver  110  over corresponding vertical conductive structures  128  and may be coupled to feed terminals  96  on the antennas  40  adjacent to side  112  over corresponding vertical conductive structures  152 . If desired, the ground conductors in traces  156  may be shorted to the ground conductors in traces  158  (e.g., over one or more conductive through-vias). Openings such as opening  152  may be formed in traces  156 . Openings such as opening  154  may be formed in traces  158 . Openings  152  and  154  may sometimes be referred to herein as slots or gaps. Opening  152  may, for example, be formed between signal and ground conductors in traces  156 . Opening  154  may, for example, be formed between signal and ground conductors in traces  158 . Vertical conductive structures  150  may extend through opening  152  to feed terminals  96  on the antennas adjacent to side  112 . Vertical conductive structures  151  may extend through opening  154  to feed terminals  96  on the antennas adjacent to side  114 . 
     The ground conductors in traces  156  may form antenna ground  92  ( FIGS. 5 and 6 ) for the antennas adjacent to side  112  whereas the ground conductors in traces  158  form antenna ground  92  for the antennas adjacent to side  114  of module  109 . At the same time, the ground conductors in traces  156  may form part of one or more coplanar waveguides (e.g., grounded coplanar waveguides) that convey signals for the antennas adjacent to side  114  whereas the ground conductors in traces  158  form part of one or more coplanar waveguides (e.g., grounded coplanar waveguides) that convey signals for the antennas adjacent to side  112 . 
     In the example of  FIG. 10 , conductive traces  156  may include a signal conductor that conveys signals at frequencies greater than 10 GHz (e.g., millimeter wave signals) for transceiver port  134 - 1 . The signal conductor in conductive traces  156  may convey the signals to feed terminal  96 - 2  on antenna resonating element  104 - 2  of antenna  40 - 2  over vertical conductive structure  151  extending through opening  154  in traces  158 . Traces  156  may include ground traces that form ground plane  92  for antenna  40 - 1  adjacent to side  112  and that form part of a coplanar waveguide that includes the signal conductor in traces  156 . Conductive traces  158  may include a signal conductor that conveys signals at frequencies greater than 10 GHz (e.g., millimeter wave signals) for transceiver port  134 - 2 . The signal conductor in conductive traces  158  may convey the signals to feed terminal  96 - 1  on antenna resonating element  104 - 1  of antenna  40 - 1  over vertical conductive structure  150  extending through opening  153  in traces  156 . Traces  158  may include ground traces that form ground plane  92  for antenna  40 - 2  adjacent to side  114  and that form part of a grounded coplanar waveguide that includes the signal conductor in traces  158 . 
     When configured in this way, antennas  40  adjacent to side  112  such as antenna  40 - 1  may convey signals over a first hemisphere above side  112  (e.g., as shown by arrow  160 ). Antennas  40  adjacent to side  114  such as antenna  40 - 2  may convey signals in a second hemisphere below side  114  (e.g., as shown by arrow  162 ). This may allow antennas  40  to perform communications cover all sides of module  109 . Ground conductors in traces  156  and  158  may serve to electromagnetically isolate antennas  40  adjacent to side  112  from antennas  40  adjacent to side  114 . In addition, forming transmission line structures  159  for antennas on two sides of module  109  using conductive traces  156  and  158  may minimize electromagnetic coupling between the signals conveyed by ports  134 - 1  and  134 - 2  of transceiver  110 , for example. 
     The example of  FIG. 10  is merely illustrative. If desired, additional layers  122  may be interposed between resonating element  104 - 2  and parasitic element  106 - 2 , between parasitic  106 - 2  transceiver  110 , between traces  158  and  156 , and/or between resonating element  104 - 1  and parasitic  106 - 1 . If desired, fewer or additional layers  122  may be formed between resonating element  104 - 1  and traces  156  and/or fewer or additional layers  122  may be formed between resonating element  104 - 2  and traces  158 . Additional layers  122  may be formed over parasitic element  106 - 1  and/or under transceiver  110 . In another suitable arrangement, substrate  120  may be formed from a single dielectric layer (e.g., antennas  40 - 1  and  40 - 2  may be embedded within a single dielectric layer such as a molded plastic layer). In yet another suitable arrangement, substrate  120  may be omitted and antennas  40 - 1  and  40 - 2  may be formed on other substrate structures or may be formed without substrates. 
     The example of  FIG. 10  in which one antenna  40 - 1  is formed adjacent to side  112  and one antenna  40 - 2  is formed adjacent to side  114  is merely illustrative. In general, any desired number of antennas  40  may be formed at side  112  and/or side  114  of substrate  120  (e.g., each having corresponding signal conductors in traces  156  or  158  and transceiver ports  134 ). The antennas adjacent to side  112  may form a first phased antenna array for conveying signals  160  whereas the antennas adjacent to side  114  may form a second phased antenna array for conveying signals  162 , if desired. 
     In the example of  FIG. 10 , antennas  40 - 1  and  40 - 2  are shown as only having a single feed for the sake of simplicity. In order to enhance the polarizations covered by antennas  40 , antennas  40 - 1  and  40 - 2  may each include two feeds such as shown in  FIG. 6 . In this scenario, each feed terminal  96  of antenna  40 - 1  may be coupled to a different corresponding signal conductor within traces  158  and to a different corresponding transceiver port  134 . Similarly, each feed terminal  96  of antenna  40 - 2  may be coupled to a different corresponding signal conductor within traces  156  and to a different corresponding transceiver port  134  (e.g., antennas  40 - 1  and  40 - 2  may have a combined total of four antenna feeds that are fed using four coplanar waveguides formed using structures  159  and four different transceiver ports  134 ). 
       FIG. 11  is a perspective view of transmission line structures  159  for antennas  40 - 1  and  40 - 2  formed at opposing sides of module  109  (e.g., as shown in  FIG. 10 ). In the example of  FIG. 11 , dielectric layers  122  are not shown for the sake of clarity. As shown in  FIG. 11 , conductive traces  156  may be formed at distance  155  from conductive traces  158  (e.g., the thickness of layer  122 - 5  of  FIG. 10  may be equal to distance  155 ). 
     Conductive traces  156  may include grounded portions  156 G that are sometimes referred to herein as grounded segments, grounded traces, grounded conductors, or ground conductors. Conductive traces  156  may include signal-level portions such as signal portion  156 P. Signal portion  156 P may sometimes be referred to herein as a signal conductor, signal trace, or micro strip. Signal conductor  156 P may be laterally interposed between two ground conductors  156 G. Signal conductor  156 P may be separated from the two adjacent ground conductors  156 G by openings  152  in traces  156 . 
     Conductive traces  158  may include grounded portions such as ground conductors  158 G and signal-level portions such signal conductor  158 P. Signal conductor  158 P may be laterally interposed between two ground conductors  158 G. Signal conductor  158 P may be separated from the two adjacent ground conductors  158 G by openings  154  in traces  158 . If desired, ground conductors  156 G may be shorted to corresponding ground conductors  158 G over vertical conductive structures  170 . Vertical conductive structures  170  may include conductive through-vias, metal pillars, metal wires, conductive pins, or any other desired vertical conductive interconnect structures. Ground conductors  156 G and  158 G may be held at a ground or reference potential, for example. Ground traces  156 G and/or  158 G may, if desired, be shorted to one or more dedicated ground ports  134  on transceiver  110  ( FIG. 8 ). 
     Signal conductor  156 P may be coupled to transceiver port  134 - 1  over vertical conductive structure  128 - 1  ( FIG. 10 ). Signal conductor  158 P may be coupled to transceiver port  134 - 2  over vertical conductive structure  128 - 2 . Signal conductor  156 P may be coupled to feed terminal  96 - 2  of antenna  40 - 2  over vertical conductor  151  and through opening  154  in traces  158  (e.g., vertical conductor  151  may extend through layers  122 - 5 ,  122 - 4 , and  122 - 3  and opening  154  in traces  158 ). Signal conductor  158 P may be coupled to feed terminal  96 - 1  of antenna  40 - 1  over vertical conductor  150  and through opening  152  in traces  156  (e.g., vertical conductor  150  may extend through layers  122 - 5 ,  122 - 6 , and  122 - 7  and through opening  152  in traces  156 ). 
     Signal conductor  156 P may convey antenna currents between transceiver port  134 - 2  and antenna feed terminal  96 - 2  on antenna  40 - 2 . Corresponding signals (e.g., millimeter wave signals) for antenna  40 - 2  may be conveyed down the longitudinal length of signal conductor  156 P (e.g., along the Y-axis of  FIG. 11 ) between the adjacent ground traces  156 G and the underlying ground traces  158 G (e.g., from vertical conductive structure  128 - 2  to vertical conductive structure  151  as shown in  FIG. 10 ). 
     Signal conductor  158 P may convey antenna currents between transceiver port  134 - 1  and antenna feed terminal  96 - 1  on antenna  40 - 1 . Corresponding signals (e.g., millimeter wave signals) for antenna  40 - 1  may be conveyed down the longitudinal length of signal conductor  158 P (e.g., along the Y-axis of  FIG. 11 ) between the adjacent ground traces  158 G and the overlying ground traces  156 G (e.g., from vertical conductive structure  128 - 1  to vertical conductive structure  150  as shown in  FIG. 10 ). 
     In this way, transmission line structures  159  may be configured to include a coplanar waveguide  159 - 2  formed from signal conductor  156 P, ground conductors  156 G, and ground conductors  158 G that conveys signals for antenna  40 - 2  and a coplanar waveguide  159 - 1  formed from signal conductor  158 P, ground conductors  158 G, and ground conductors  156 G that conveys signals for antenna  40 - 1  (e.g., coplanar waveguide  159 - 2  may form a first transmission line  64  for antenna  40 - 2  having a signal path  91  formed from conductor  156 P and ground path  94  formed from traces  156 G and  158 G, whereas coplanar waveguide  159 - 1  may form a second transmission line  64  for antenna  40 - 1  having a signal path  91  formed from conductor  158 P and ground path  94  formed from traces  156 G and  158 G as shown in  FIG. 4 ). Transmission lines  159 - 1  and  159 - 2  may sometimes be referred to as grounded coplanar transmission lines in scenarios where vertical conductive structures  170  are formed between traces  156 G and  158 G. Structures  170  may be omitted if desired. 
     When configured in this way, coplanar waveguide signal conductor  156 P for antenna  40 - 2  may be interposed or located between antenna  40 - 1  and coplanar waveguide signal conductor  158 P for antenna  40 - 1 . Similarly, signal conductor  158 P for antenna  40 - 1  may be interposed between antenna  40 - 2  and signal conductor  156 P for antenna  40 - 2 . Ground traces  156 G may extend across the lateral area of module  109  under antenna resonating element  104 - 1  and may form antenna ground plane  92  ( FIGS. 5 and 6 ) for antenna  40 - 1 . Similarly, ground traces  158 G may extend across the lateral area of module  109  over resonating element  104 - 2  and may form antenna ground plane  92  for antenna  40 - 2 . At the same time, ground traces  156 G and  158 G may serve to shield antenna  40 - 1  from antenna  40 - 2  and may serve to mitigate electromagnetic coupling between signal lines  156 P and  158 P (e.g., ground traces  156 G may isolate signal conductor  156 P from signals conveyed by signal conductor  158 P and ground traces  158 G may isolate signal conductor  158 P from signals conveyed by signal conductor  156 P). This may, for example, minimize interference between ports  134 - 1  and  134 - 2  and between signals conveyed by antennas  40 - 1  and  40 - 2 . 
     The example of  FIG. 11  is merely illustrative. In general, layer  156  may include a different respective signal conductor  156 P for each feed terminal  96  on the antennas  40  adjacent to side  114  of module  109 . For example, in scenarios where module  109  includes two antennas  40  adjacent to side  114  each having two feeds (e.g., as shown in  FIG. 6 ), traces  156  may include four signal conductors  156 P, each separated from the other signal conductors  156 P by at least one ground trace  156 G. Similarly, in scenarios where module  109  includes four antennas  40  adjacent to side  112  each having two feeds, traces  158  may include eight signal conductors  156 P, each separated from the other signal conductors  158 P by at least one ground trace  158 G. As another example, in scenarios where module  109  includes four antennas  40  adjacent to side  112  and four antennas  40  adjacent to side  114 , each having two feeds, structures  159  may include sixteen coplanar waveguides, traces  156  may include eight signal conductors  156 P separated by ground conductors  156 G for the antennas adjacent to side  114 , and traces  158  may include eight signal conductors  158 P separated by ground conductors  158 G for the antennas adjacent to side  112 . Each signal conductor  156 P may be coupled to antenna resonating elements  104  adjacent to side  114  through the same opening in traces  158  or through different openings in traces  158  (e.g., through respective openings between signal and ground conductors in traces  158 , through openings within ground conductors  158 G, etc.). Each signal conductor  158 P may be coupled to antenna resonating elements  104  adjacent to side  112  through the same opening in traces  156  or through different openings in traces  156 . Forming the transmission lines for antennas  40  using coplanar waveguide structures  159  may ensure that each of the signal conductors are sufficiently isolated regardless of the number of antennas  40  and feeds  100  that are formed adjacent to one or both sides of module  109 . If desired, both waveguide structures of the type shown in  FIGS. 8 and 9  may be formed together with waveguide structures of the type shown in  FIGS. 10 and 11  within the same module  109  (e.g., for feeding different antennas on one and/or both sides of module  109 ). 
       FIG. 12  is a top-down view showing how ports  134  may be arranged on transceiver  110  of  FIGS. 8 and 10 . As shown in  FIG. 12 , ports  134  may be arranged around the periphery of transceiver  110 . Ports  134  may include signal ports  134 S that are each coupled to a corresponding signal conductor in the coplanar waveguide structures of module  109  (e.g., coplanar waveguide structures  137  of  FIGS. 8 and 9  or coplanar waveguide structures  159  of  FIGS. 10 and 11 ). Ports  134  may include ground ports  134 G that each coupled to a corresponding ground antenna feed terminal  98  ( FIGS. 5 and 6 ). Transceiver circuitry  110  may, for example, include at least one signal port  134 S and at least one ground port  134 G for each antenna feed  100  that is formed on module  109 . As shown in  FIG. 12 , each signal port  134 S may be interposed between two adjacent ground ports  134 G (e.g., each ground port  134 G may be interposed between two signal ports  134 S). Arranging ports  134  in this way may, for example, further enhance the isolation between signal ports  134 S at the interface between transceiver  110  and vertical conductive structures  128  ( FIGS. 8 and 10 ). This example is merely illustrative and, in general, ports  134  may be arranged in any desired manner. 
     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.