Abstract: An electronic device may be provided with a phased antenna array that radiates at a frequency greater than 10 GHz through a display. The array may include a dielectric resonator antenna having a dielectric column. The dielectric column may have a first surface mounted to a circuit board and a second surface that faces the display. A conductive cap may be formed on the second surface. The conductive cap may allow the dimensions of dielectric column to be reduced while still allowing the dielectric resonator antenna to cover a frequency band of interest. If desired, the phased antenna array may include multiple sets of dielectric resonator antennas for covering different frequency bands. The sets may have different dielectric column heights and/or different conductive cap sizes.

Abstract: An electronic device may be provided with a phased antenna array that radiates at a frequency greater than 10 GHz. The array may include a dielectric resonator antenna having a dielectric column with non-planar sidewalls that include planar portions and corrugated portions with grooves and ridges, that include sidewall steps, and/or that include angled sidewall portions. The dielectric resonator antenna may include a first dielectric column and a second dielectric column stacked on the first dielectric column. The second column may be narrower and may have a higher dielectric constant than the first column or may have the same width but a lower dielectric constant than the first column. This may serve to broaden the bandwidth of the dielectric resonator antenna relative to scenarios where the dielectric resonator antenna includes only a single dielectric resonating element having only planar sidewalls.

Abstract: An electronic device may be provided with a phased antenna array that radiates at a frequency greater than 10 GHz. The array may include a first set of dielectric resonator antennas arranged in a first row and a second set of dielectric resonator antennas in a second row offset from the first row. Each dielectric resonator antenna may have dielectric resonating element with a base portion and a stepped portion. The stepped portions of the antennas in the first set may be arranged to be distant from the stepped portions of the antennas in the second set. The antennas in the first set may be arranged to be more distant from an electronic device sidewall than the antennas in the second set. Configured in this manner, the array may exhibit reduced inter-coupling between dielectric resonator antennas in the first set and dielectric resonator antennas in the second set.

Abstract: An electronic device may include an antenna and a coaxial cable coupled to the antenna. The coaxial cable may have a signal conductor coupled to an antenna resonating element of the antenna and a ground conductor coupled to an antenna ground of the antenna. The ground conductor may include an ungrounded segment that is separated from the antenna ground by a gap. A capacitive coupling between the ground conductor in the ungrounded segment and the antenna ground via the gap may form an impedance matching component for the coaxial cable. A dielectric retention layer may overlap the coaxial cable and hold the coaxial cable in place relative to the antenna ground to maintain the gap.

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 include a conductive housing with a rear wall and a sidewall. A display may be mounted to the sidewall and may include a conductive display structure separated from the sidewall by a slot. An antenna arm may be interposed between the conductive display structure and the rear wall. A first inductor may couple the conductive display structure to the housing and may compensate for a distributed capacitance between the antenna arm and the conductive display structure. A second inductor may couple the antenna arm to the rear wall and may compensate for a distributed capacitance between the antenna arm and the rear wall. A speaker may be co-located with the antenna. A third inductor may couple the antenna arm to the rear wall to allow antenna currents to bypass the speaker.

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

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

Abstract: An electronic device may be provided with a cover layer and a phased antenna array mounted against the cover layer. Each antenna in the array may include a first patch element that is directly fed using first and second feeds and a second patch element that is directly fed using third and fourth feeds. A slot element may be formed in the first patch element. The first patch element may radiate in a first frequency band through the cover layer. The slot element may radiate in a second frequency band that is higher than the first frequency band through the cover layer. The second patch element may indirectly feed the slot element. Locating the radiating elements for each frequency band in the same plane may allow the antenna to radiate through the cover layer in both frequency bands with satisfactory antenna efficiency.

Abstract: An electronic device may be provided with a phased antenna array that radiates at a frequency greater than 10 GHz. The array may include a dielectric resonator antenna having a dielectric column with non-planar sidewalls that include planar portions and corrugated portions with grooves and ridges, that include sidewall steps, and/or that include angled sidewall portions. The dielectric resonator antenna may include a first dielectric column and a second dielectric column stacked on the first dielectric column. The second column may be narrower and may have a higher dielectric constant than the first column or may have the same width but a lower dielectric constant than the first column. This may serve to broaden the bandwidth of the dielectric resonator antenna relative to scenarios where the dielectric resonator antenna includes only a single dielectric resonating element having only planar sidewalls.

Abstract: An electronic device may have a first conductive sidewall at an upper end, a second conductive sidewall at a lower end, and a conductive rear wall. First and second antennas may be formed at the upper end and may include slots with edges defined by the first sidewall and the rear wall. Third, fourth, fifth, and sixth antennas may be formed at the lower end and may include slots with edges defined by the second sidewall and the rear wall. Each antenna may cover multiple frequency bands. First order and third order modes of the slots may contribute to the frequency responses of the third through sixth antennas. A display controller may be mounted at the lower end and may impose a lower limit on the frequencies covered by the third through sixth antennas. The first and second antennas may cover lower frequencies than the third through sixth antennas.

Abstract: An electronic device may be provided with a phased antenna array that radiates at a frequency greater than 10 GHz through a display. The array may include a dielectric resonator antenna having a dielectric column. The dielectric column may have a first surface mounted to a circuit board and a second surface that faces the display. A conductive cap may be formed on the second surface. The conductive cap may allow the dimensions of dielectric column to be reduced while still allowing the dielectric resonator antenna to cover a frequency band of interest. If desired, the phased antenna array may include multiple sets of dielectric resonator antennas for covering different frequency bands. The sets may have different dielectric column heights and/or different conductive cap sizes.

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

Abstract: An electronic device may have a first conductive sidewall at an upper end, a second conductive sidewall at a lower end, and a conductive rear wall. First and second antennas may be formed at the upper end and may include slots with edges defined by the first sidewall and the rear wall. Third, fourth, fifth, and sixth antennas may be formed at the lower end and may include slots with edges defined by the second sidewall and the rear wall. Each antenna may cover multiple frequency bands. First order and third order modes of the slots may contribute to the frequency responses of the third through sixth antennas. A display controller may be mounted at the lower end and may impose a lower limit on the frequencies covered by the third through sixth antennas. The first and second antennas may cover lower frequencies than the third through sixth antennas.

Abstract: An electronic device may include a conductive housing with a rear wall and a sidewall. A display may be mounted to the sidewall and may include a conductive display structure separated from the sidewall by a slot. An antenna arm may be interposed between the conductive display structure and the rear wall. A first inductor may couple the conductive display structure to the housing and may compensate for a distributed capacitance between the antenna arm and the conductive display structure. A second inductor may couple the antenna arm to the rear wall and may compensate for a distributed capacitance between the antenna arm and the rear wall. A speaker may be co-located with the antenna. A third inductor may couple the antenna arm to the rear wall to allow antenna currents to bypass the speaker.

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 circuitry for conveying radio-frequency signals greater than 10 GHz. The wireless circuitry may include a phased antenna array that transmits a steerable signal beam and independent antennas that are separate from the array. The array may be coupled to a first transceiver and the independent antennas may be coupled to a second transceiver. Power amplifier stages may be coupled between the second transceiver and the independent antennas to boost the gain of the independent antennas. If desired, the array and the independent antennas may be coupled to ports of the same transceiver. In this arrangement, each independent antenna may include an antenna feed that is coupled to a respective pair of ports on the transceiver. This may serve to boost the gain of the independent antennas without power amplifier circuitry. The independent antennas may have smaller footprints than the phased antenna array.

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.