Abstract: An electronic device may include a curved cover layer and an antenna. The antenna may include a ground and a resonating element on a curved surface of a substrate. The curved surface may have a curvature that matches that of the cover layer. The resonating element may include first, second, and third arms fed by a feed. The first arm and a portion of the ground may form a loop antenna resonating element. The second arm and the first arm may form an inverted-F antenna resonating element, where a portion of the first arm forms a return path to the antenna ground for the inverted-F antenna resonating element. A gap between the first and second arms may form a distributed capacitance. The third arm may form an L-shaped antenna resonating element. The antenna may have a wide bandwidth from below 2.4 GHz to greater than 9.0 GHz.

Abstract: An electronic device may be provided with a dielectric cover layer, a dielectric substrate, and a phased antenna array on the dielectric substrate for conveying millimeter wave signals through the dielectric cover layer. The array may include conductive traces mounted against the dielectric layer. The conductive traces may form patch elements or parasitic elements for the phased antenna array. The dielectric layer may have a dielectric constant and a thickness selected to form a quarter wave impedance transformer for the array at a wavelength of operation of the array. The substrate may include fences of conductive vias that laterally surround each of the antennas within the array. When configured in this way, signal attenuation, destructive interference, and surface wave generation associated with the presence of the dielectric layer over the phased antenna array may be minimized.

Abstract: An electronic device may be provided with wireless communications circuitry and control circuitry. The wireless communications circuitry may include centimeter and millimeter wave transceiver circuitry and a phased antenna array. A dielectric cover may be formed over the phased antenna array. The phased antenna array may transmit and receive wireless radio-frequency signals through the dielectric cover. The dielectric cover may have first and second opposing surfaces. The second surface may face the phased antenna array and may have a curvature. The curvature of the second surface may include one or more recessed regions of the dielectric cover. The one or more recessed regions of the second surface may serve to maximize and broaden the coverage area for the phased antenna array. The first surface may be conformal to other structures in the electronic device.

Abstract: An electronic device may be provided with a dielectric cover layer, a dielectric substrate, and a phased antenna array on the dielectric substrate for conveying millimeter wave signals through the dielectric cover layer. The array may include conductive traces mounted against the dielectric layer. The conductive traces may form patch elements or parasitic elements for the phased antenna array. The dielectric layer may have a dielectric constant and a thickness selected to form a quarter wave impedance transformer for the array at a wavelength of operation of the array. The substrate may include fences of conductive vias that laterally surround each of the antennas within the array. When configured in this way, signal attenuation, destructive interference, and surface wave generation associated with the presence of the dielectric layer over the phased antenna array may be minimized.

Abstract: An electronic device may be provided with a dielectric cover layer, a dielectric substrate, and a phased antenna array on the dielectric substrate for conveying millimeter wave signals through the dielectric cover layer. The array may include conductive traces mounted against the dielectric layer. The conductive traces may form patch elements or parasitic elements for the phased antenna array. The dielectric layer may have a dielectric constant and a thickness selected to form a quarter wave impedance transformer for the array at a wavelength of operation of the array. The substrate may include fences of conductive vias that laterally surround each of the antennas within the array. When configured in this way, signal attenuation, destructive interference, and surface wave generation associated with the presence of the dielectric layer over the phased antenna array may be minimized.

Abstract: A system such as a vehicle may have windows. A window may have a structural window layer formed from one or more glass layers. A conductive coating such as an infrared-light blocking coating or other optical filter layer may be formed on the window. The conductive coating may include one or more silver layers or other conductive material. Unpatterned portions of the conductive coating are conductive along orthogonal dimensions. A region of the conductive coating may have parallel line-shaped openings that render the coating conductive in only a single dimension while enhancing radio transparency. Another region of the conductive coating may have a two-dimensional pattern of openings such as a mesh-shaped opening formed from intersecting straight and/or curved lines. In this region, the coating is locally rendered insulating and radio-frequency transparent. Antennas and ohmic heating elements may be formed in the coating.

Abstract: An electronic device may be provided with a dielectric cover layer and a conductive layer on the dielectric cover layer. The conductive layer may define an opening. A dielectric spacer may be mounted to the cover layer within the opening. A substrate may be mounted to the spacer. Vertical conductive structures may extend from the conductive layer to the substrate and may laterally surround the spacer. A phased antenna array may be formed on the substrate and aligned with the opening. The cover layer may have a dielectric constant and thickness that are selected to form a quarter wave impedance transformer for the array at a wavelength of operation of the array. The spacer and the conductive structures may exhibit a cavity resonance at the wavelength. The array and the conductive structures may radiate radio-frequency signals at millimeter wave frequencies through the dielectric cover layer.

Abstract: An electronic device may be provided with an antenna module and a phased antenna array on the module. The module may include a logic board, an antenna board surface-mounted to the logic board, and a radio-frequency integrated circuit (RFIC) mounted surface-mounted to the logic board. The phased antenna array may include antennas embedded in the antenna board. The antennas may radiate at centimeter and/or millimeter wave frequencies. The logic board may form a radio-frequency interface between the RFIC and the antennas. Transmission lines in the logic board and the antenna board may include impedance matching segments that help to match the impedance of the RFIC to the impedance of the antennas. The module may efficiently utilize space within the device without sacrificing radio-frequency performance.

Abstract: A wireless communication system comprises a base station and one or more relay docks and transmits directional wave signals between components using high frequency waves, such as millimeter waves. A beam forming decision engine utilizes position information collected from one or more position or motion sensors of a user device to determine a direction in which to form a directional wave signal being transmitted between components of the wireless communication system.

Abstract: An electronic device may be provided with wireless circuitry. The wireless circuitry may include one or more antenna structures and transceiver circuitry such as millimeter wave transceiver circuitry. Antenna structures in the wireless circuitry may include patch antennas that are organized in a phased antenna array. Each patch antenna may include an antenna resonating element and a parasitic element. The parasitic element for the patch antenna may have dielectric-filled openings formed between coplanar parasitic conductors. The parasitic conductors may include a central parasitic conductor, four rectangular parasitic conductors formed around the central parasitic conductor, and corner parasitic conductors formed at the corners of the parasitic element. The corner parasitic conductors may be non-rectangular. For example, the corner parasitic conductors may have first and second perpendicular edges and a straight or curved third edge that joins the first and second edges.

Abstract: A wireless communication system comprises a base station and one or more relay docks and transmits directional wave signals between components using high frequency waves, such as millimeter waves. A beam forming decision engine utilizes position information collected from one or more position or motion sensors of a user device to determine a direction in which to form a directional wave signal being transmitted between components of the wireless communication system.

Abstract: An electronic device may include a phased antenna array mounted in a conductive cavity for conveying radio-frequency signals above 10 GHz. The cavity may include sidewalls extending from a rear wall. The array may include rectangular patches each having first and second perpendicular edges. Each of the first edges in the array may be aligned with a first axis. Each of the second edges in the array may be aligned with a second axis perpendicular to the first axis. The first and second axes may be oriented at 45 degrees with respect to each of the sidewalls of the cavity. Each patch may be fed using first and second positive antenna feed terminals that cover orthogonal linear polarizations. The cavity may prevent interference while symmetrically loading the impedance of both the first and second positive antenna feed terminals in each patch.

Abstract: An electronic device such as a wristwatch may be provided with wireless circuitry and a display having a display module and a cover layer. The display module may include a dielectric layer. Touch sensor electrodes may be formed from conductive traces on the dielectric layer. An antenna may be embedded within the display module. The antenna may include an antenna resonating element formed from a grid of intersecting conductive traces on the dielectric layer. The grid may have edges that define a lateral outline of the antenna resonating element. The outline may have a length that configures the antenna to radiate at a desired frequency. The antenna resonating element may be formed from indium tin oxide and may be substantially transparent.

Abstract: An electronic device may be provided with a dielectric cover and a phased antenna array for conveying millimeter wave signals. A conductive pocket may be mounted to the cover. The pocket may include a conductive rear wall and conductive sidewalls that extend from a periphery of the rear wall to the cover. The array may be mounted to the rear wall and may convey signals through the cover. The sidewalls may extend from the cover at non-zero angles with respect to the normal axis of the cover. The shape of the pocket and the cover may be selected so that the pocket is non-resonant at frequencies handled by the array, to mitigate destructive interference within the pocket, to block surface waves from propagating along the cover, and to tweak the radiation pattern of the array to exhibit a desired shape and directionality.

Abstract: An electronic device may be provided with wireless circuitry that includes a radio-frequency transceiver circuit and an antenna. The antenna may be a patch antenna formed from a patch antenna resonating element and an antenna ground. The patch antenna resonating element may be formed from a metal patch on a printed circuit board. The antenna ground may be formed from a metal housing having a planar rear wall that lies in a plane parallel to the metal patch. The radio-frequency transceiver circuit may be coupled to the metal patch through traces on the printed circuit and may be coupled to rear wall of the housing through a screw and a screw boss in the housing. Buttons and other electrical components may be mounted on the printed circuit board and may be coupled to control circuitry on the printed circuit board through the metal patch.

Abstract: An electronic device may include a substrate and a conductive layer on the substrate. The conductive layer may be patterned to form a first region and a second region that surrounds and defines the shape of the first region. The first region may be formed from a continuous portion of the conductive layer. The second region may include a grid of openings that divides the conductive layer into an array of patches. The first region may form an antenna resonating element for an antenna. The second region may block antenna currents from the antenna resonating element and may be transparent to radio-frequency electromagnetic waves. The openings may have a width that is too narrow to be discerned by the human eye. This may configure the first and second regions to appear as a single continuous conductive layer despite the fact that an antenna resonating element is formed therein.

Abstract: An electronic device may be provided with a phased antenna array for conveying millimeter wave signals. The array may be mounted to a substrate that includes transmission line layers having a first dielectric permittivity and antenna layers having a second dielectric permittivity that is less than the first dielectric permittivity. A ground plane may be interposed between the antenna layers and the transmission line layers. The array may be mounted to the antenna layers and transceiver circuitry may be mounted to the transmission line layers. Transmission line traces may be formed on the transmission line layers. The relatively high permittivity of the first set of dielectric layers may allow the transmission line traces to be routed relatively close together with minimal electromagnetic interference. The relatively low permittivity of the second set of dielectric layers may allow the array to operate with satisfactory antenna efficiency, gain, and bandwidth.

Abstract: An electronic device may be provided with wireless communications circuitry and control circuitry. The wireless communications circuitry may include millimeter wave transceiver circuitry and a phased antenna array. The phased antenna array may transmit and receive millimeter wave signals. Beam steering circuitry may be coupled to the phased antenna array and may be adjusted to steer the millimeter wave signals in a particular direction. The control circuitry may track the location of an external device using sensor data. The control circuitry may control a mechanical positioner to mechanically adjust an orientation of the phased antenna array and/or may control the beam steering circuitry to steer the millimeter wave signals towards the location of the external device. In this way, a line of sight millimeter wave communications link may be maintained between the phased antenna array and the external device even if the external device moves over time.

Abstract: An electronic device may have a display. A display cover layer and a transparent inner display member may overlap a display pixel layer. The display pixel layer may have an array of display pixels for displaying images for a user. A touch sensor layer may be interposed between the display pixel layer and the transparent display member. A ferromagnetic shielding layer may be mounted below the display pixel layer. A flexible printed circuit containing coils of metal signal lines that form a near-field communications loop antenna may be interposed between the ferromagnetic shielding layer and the display pixel layer. A non-near-field antenna such as an inverted-F antenna may have a resonating element mounted on an inner surface of the display cover layer. The resonating element may be interposed between the transparent display member and the display cover layer.

Abstract: An electronic device may be provided with wireless communications circuitry and control circuitry. The wireless communications circuitry may include centimeter and millimeter wave transceiver circuitry and a phased antenna array. A dielectric cover may be formed over the phased antenna array. The phased antenna array may transmit and receive antenna signals through the dielectric cover. The dielectric cover may have a surface that faces the phased antenna array and may have a curvature. The antenna elements of the phased antenna array may be formed on a dielectric substrate. The dielectric substrate may have one or more thinned regions between antenna elements of the phased antenna array to reduce surface wave interference between adjacent antennas. The dielectric substrate may have a smaller thickness in the thinned region than in the regions under the antenna elements. The dielectric substrate may be totally removed in the thinned region.