Abstract: An electronic device such as a wristwatch may be provided with a phased antenna array for conveying first signals at a first frequency between 10 GHz and 300 GHz and a non-millimeter wave antenna for conveying second signals at a second frequency below 10 GHz. The device may include conductive housing sidewalls and a display. Conductive structures in the display and the conductive housing sidewalls may define a slot element in the non-millimeter wave antenna. The phased antenna array may be mounted within the slot element, aligned with a spatial filter in the display, or aligned with a dielectric window in the conductive housing sidewalls. Control circuitry may process signals transmitted by the phased antenna array and a reflected version of the transmitted signals that has been received by the phased antenna array to detect a range between the device and an external object.

Abstract: An electronic device such as a wristwatch may be provided with a phased antenna array for conveying first signals at a first frequency between 10 GHz and 300 GHz and a non-millimeter wave antenna for conveying second signals at a second frequency below 10 GHz. The device may include conductive housing sidewalls and a display. Conductive structures in the display and the conductive housing sidewalls may define a slot element in the non-millimeter wave antenna. The phased antenna array may be mounted within the slot element, aligned with a spatial filter in the display, or aligned with a dielectric window in the conductive housing sidewalls. Control circuitry may process signals transmitted by the phased antenna array and a reflected version of the transmitted signals that has been received by the phased antenna array to detect a range between the device and an external object.

Abstract: An electronic device may be provided with a phased antenna array and a display cover layer. The phased antenna array may include a dielectric resonator antenna. The dielectric resonator antenna may include a dielectric resonating element embedded in a lower permittivity dielectric substrate. The substrate and the resonating element may be mounted to a flexible printed circuit. A slot may be formed in ground traces on the flexible printed circuit and aligned with the resonating element. The slot may excite resonant modes of the resonating element. The resonating element may convey corresponding radio-frequency signals through the cover layer. A dielectric matching layer may be interposed between the resonating element and the cover layer. If desired, the slot may radiate additional radio-frequency signals and the matching layer may have a tapered shape. Dielectric resonator antennas for covering different polarizations and frequencies may be interleaved across the array.

Abstract: An electronic device may be provided with a phased antenna array and a display cover layer. The phased antenna array may include a probe-fed dielectric resonator antenna. The antenna may include a dielectric resonating element mounted to a flexible printed circuit. A feed probe may be formed from a patch of conductive traces on a sidewall of the resonating element. The feed probe may excite resonant modes of the resonating element. The resonating element may convey corresponding radio-frequency signals through the display cover layer. An additional feed probe may be mounted to an orthogonal sidewall of the resonating element for covering additional polarizations. Probe-fed dielectric resonator antennas for covering different polarizations and frequencies may be interleaved across the phased antenna array.

Abstract: An electronic device may include a millimeter wave antenna having a ground plane, resonating element, feed, and parasitic element. The resonating element may include first, second, and third layer of traces that are shorted together. The second traces may be interposed between the first and third traces and the third traces may be interposed between the second traces and the parasitic. The third traces may have a width that is less than the widths of the second and third traces. The third traces and the parasitic may define a constrained volume having an associated cavity resonance that lies outside of a frequency band of interest. If desired, the resonating element may include a single layer of conductive traces having a grid of openings that disrupt impedance in a transverse direction, thereby mitigating the trapping of energy within the frequency band of interest between the resonating element and the parasitic.

Abstract: An electronic device may be provided with wireless circuitry that includes a phased antenna array. The array may include multiple antennas each having multiple antenna feeds for covering different polarizations. Control circuitry may control the wireless circuitry to transmit signals at millimeter or centimeter wave frequencies using a first set of feeds in the array and at least one selected phase. The wireless circuitry may receive the signals transmitted by the first set of feeds using a second set of feeds in the array. The control circuitry may gather phase measurements for the received signals and may compare the phase measurements to the selected phase to generate phase difference values. The control circuitry may perform external object proximity detection operations based on the phase difference values. The control circuitry may control the wireless circuitry to cycle through different combinations of antenna feeds for the first and second sets.

Abstract: An electronic device may be provided with a transceiver, a substrate, and antennas mounted to the substrate. The transceiver and antennas may convey signals between 10 GHz and 300 GHz. A radio-frequency connector may be mounted to the substrate. A coaxial cable may couple the transceiver to the connector. A stripline in the substrate may couple the connector to the antennas. Impedance matching structures may be embedded in the substrate for matching an impedance of the stripline to an impedance of the coaxial cable. The impedance matching structures may include a fence of conductive vias, landing pads, and a volume of the dielectric substrate defined by the fence of conductive vias and the landing pads. The impedance matching structures may be configured to perform impedance matching over a relatively wide bandwidth that includes the frequency band of operation for the antennas.

Abstract: An electronic device may include a millimeter wave antenna having a ground plane, resonating element, feed, and parasitic element. The resonating element may include first, second, and third layer of traces that are shorted together. The second traces may be interposed between the first and third traces and the third traces may be interposed between the second traces and the parasitic. The third traces may have a width that is less than the widths of the second and third traces. The third traces and the parasitic may define a constrained volume having an associated cavity resonance that lies outside of a frequency band of interest. If desired, the resonating element may include a single layer of conductive traces having a grid of openings that disrupt impedance in a transverse direction, thereby mitigating the trapping of energy within the frequency band of interest between the resonating element and the parasitic.

Abstract: An electronic device may be provided with a phased antenna array and a display cover layer. The phased antenna array may include a probe-fed dielectric resonator antenna. The antenna may include a dielectric resonating element mounted to a flexible printed circuit. A feed probe may be formed from a patch of conductive traces on a sidewall of the resonating element. The feed probe may excite resonant modes of the resonating element. The resonating element may convey corresponding radio-frequency signals through the display cover layer. An additional feed probe may be mounted to an orthogonal sidewall of the resonating element for covering additional polarizations. Probe-fed dielectric resonator antennas for covering different polarizations and frequencies may be interleaved across the phased antenna array.

Abstract: An electronic device may be provided with a phased antenna array and a display cover layer. The phased antenna array may include a dielectric resonator antenna. The dielectric resonator antenna may include a dielectric resonating element embedded in a lower permittivity dielectric substrate. The substrate and the resonating element may be mounted to a flexible printed circuit. A slot may be formed in ground traces on the flexible printed circuit and aligned with the resonating element. The slot may excite resonant modes of the resonating element. The resonating element may convey corresponding radio-frequency signals through the cover layer. A dielectric matching layer may be interposed between the resonating element and the cover layer. If desired, the slot may radiate additional radio-frequency signals and the matching layer may have a tapered shape. Dielectric resonator antennas for covering different polarizations and frequencies may be interleaved across the array.

Abstract: An electronic device may include a millimeter wave transceiver, a first antenna having a first resonating element at a first side of a substrate, and a second antenna having a second resonating element at a second side of the substrate. A first coplanar waveguide may convey millimeter wave signals between the transceiver and the first resonating element and a second coplanar waveguide may convey millimeter wave signals between the transceiver and the second resonating element. The first coplanar waveguide may be coupled to the first resonating element through the second coplanar waveguide. The second coplanar waveguide may be coupled to the second resonating element through the first coplanar waveguide. Ground conductors in the coplanar waveguides may form antenna ground planes for the first and second antennas while serving to maximize electromagnetic decoupling between the coplanar waveguides and thus isolation between the ports of the transceiver.

Abstract: An electronic device may be provided antennas and control circuitry. The antennas may be arranged in an array of unit cells. Each unit cell may include a first antenna that conveys signals in a first frequency band higher than 10 GHz and a second antenna that conveys radio-frequency signals in a second frequency band higher than the first frequency band. A first of the unit cells may be provided with a first set of antennas that transmits radio-frequency signals in a third frequency band higher than the second frequency band. A second of the antenna unit cells may be provided with a second set of antennas that receives the radio-frequency signals after being reflected off of external objects. The control circuitry may perform spatial ranging operations by processing the transmitted and received signals in the second frequency band.

Abstract: An electronic device may be provided with a display and a phased array antenna that transmits radio-frequency signals at frequencies greater than 10 GHz. The display may include a conductive layer that is used to form pixel circuitry and/or touch sensor electrodes. A filter may be formed from conductive structures within the conductive layer. The conductive structures may include an array of conductive patches separated by slots or may include conductive paths that define an array of slots. The filter may include an additional array of conductive patches stacked under the array of conductive patches to allow the slots to be narrower than would be resolvable to the unaided human eye. The periodicity of the conductive structures and the slots in the filter may be selected to tune a cutoff frequency of the filter to be greater than frequencies handled by the phased antenna array.

Abstract: An electronic device may be provided with antenna structures that convey radio-frequency signals greater than 10 GHz. The antenna structures may include overlapping first and second patches. The first patch may include a hole. A transmission line for the second patch may include a conductive via extending through the hole. The via may be coupled to a first end of a trace. A second end of the trace may be coupled to a feed terminal on the second patch over an additional via. The hole may be located within a central region of the first patch to allow the via to pass through the hole without electromagnetically coupling to the first patch. If desired, adjustable impedance matching circuits may be used to couple selected impedances to the antenna feeds that help ensure that the first and second patch antennas are sufficiently isolated from each other.

Abstract: An electronic device may be provided with a phased antenna array, control circuitry, and a codebook. The control circuitry may control the phased antenna array to form a signal beam at a beam steering angle selected from a set of beam steering angles identified by the codebook. The set of beam steering angles may be evenly distributed along a two-dimensional or three-dimensional spiral path. The control circuitry may control the phased antenna array to sweep over the set of beam steering angles until external wireless equipment is found. Distributing the set of beam steering angles in this way may minimize the size of the codebook while allowing the phased antenna array to cover as much of its field of view as possible with satisfactory gain.

Abstract: Methods and systems include reducing or mitigating interference by sweeping multiple beams used to communicate between a wireless network base station and an electronic device. The multiple beams include beams having different sidelobe directions. The electronic device selects, using a processor of the electronic device, a beam from the multiple beams. Furthermore, selecting the beam includes selecting the beam having a lowest level of interference of the multiple beams due to a sidelobe direction of the beam. The electronic device then communicates with the wireless network base station using the selected beam.

Abstract: An electronic device may be provided with control circuitry and wireless circuitry. The wireless circuitry may include a phased antenna array and a radio-frequency integrated circuit having transmit and receive ports. The array may include a first set of stacked patch antennas coupled to the transmit ports and a second set of stacked patch antennas coupled to the receive ports. The integrated circuit may transmit ranging signals at millimeter wave frequencies using the transmit ports and the first set of antennas. The integrated circuit may receive a reflected version of the transmitted ranging signals that has been reflected off of an external object using the receive ports and the second set of antennas. The control circuitry may identify a distance between the electronic device and the external object based on the transmitted and received signals.

Abstract: An electronic device may be provided with millimeter wave transceiver circuitry and an antenna having a ground and a resonating element. The resonating element may include first and second patches symmetrically distributed about an axis. The antenna may be fed using an antenna feed having a first feed terminal coupled to both the first and second patches and a second feed terminal coupled to the ground. The first feed terminal may be coupled to the first patch at a side closest to the second patch and may be coupled to the second patch at a side closest to the first patch. The first and second patches may be shorted to the ground if desired. Antenna currents on the first patch may be 180 degrees out of phase with antenna currents on the second patch. The antenna may be arranged in an array of antennas with different polarizations.

Abstract: An electronic device may be provided with wireless circuitry that includes a phased antenna array. The array may include first, second, and third rings of antennas on a dielectric substrate that cover respective first, second, and third communications bands greater than 10 GHz. The second ring of antennas may surround the first ring of antennas. The third ring of antennas may be formed over the second ring of antennas. Parasitic elements may be formed over the first ring of antennas to broaden the bandwidth of the first ring of antennas. Beam steering circuitry may be coupled to the rings of antennas. Control circuitry may control the beam steering circuitry to steer a beam of wireless signals in one or more of the first, second, and third communications bands. The array may exhibit relatively uniform antenna gain regardless of the direction in which the beam is steered.

Abstract: An electronic device may be provided with wireless circuitry including first and second patch antennas. The first patch antenna may include a first resonating element formed over a ground plane. The second patch antenna may include a second resonating element over the first resonating element. A cross-shaped parasitic element may be formed over the second resonating element. First and second feed terminals may be coupled to the second resonating element. An opening may be formed in the first resonating element. First and second transmission lines may be coupled to the first and second feed terminals through the opening. The cross-shaped parasitic element may include arms that overlap the first and second feed terminals. The first resonating element may cover first frequencies between 10 GHz and 300 GHz and the second resonating element may cover second frequencies that are higher than the first frequencies.