Abstract: A radio frequency system package may include waveguides and loading blocks. The loading blocks may include dielectric material having a high dielectric constant between 13 and 20. Additionally, the loading blocks may be made of mold, epoxy, or the like material, and the loading blocks may fit into a region cut out of the waveguides. Moreover, the loading blocks may lower the cut-off frequency for wireless communication otherwise provided by the waveguides without the loading blocks (e.g., 28 GHz). In particular, the loading blocks may facilitate communication in low mmWave frequencies, such as 24 GHz.

Abstract: An electronic device may be provided with a flexible printed circuit and a rigid printed circuit mounted to the flexible printed circuit using a board-to-board (B2B) connector. The flexible printed circuit may include signal conductors coupled to one or more antennas on the rigid printed circuit through the B2B connector. A given one of the signal conductors may include a phase shifter segment on the flexible printed circuit and/or a thick impedance matching segment on the rigid printed circuit that help to form a smooth impedance transition from the flexible printed circuit to the rigid printed circuit and the antenna(s). The B2B connector may include signal contacts interleaved with a ground contacts. The B2B connector may include ground bars laterally surrounding the signal and ground contacts to maximize the strength of mechanical coupling between the flexible printed circuit and the rigid printed circuit.

Abstract: An electronic device may be provided with an antenna having a resonating element and a light source module mounted to a flexible printed circuit and a metal cowling. The module may emit light through a rear housing wall. The printed circuit may be interposed between the metal cowling and a conductive support plate in the rear housing wall. The printed circuit may include a ground trace coupled to the resonating element. A dimpled pad may couple the ground trace to the support plate. Compressive foam may be used to exert a force against the flexible printed circuit that presses the dimpled pad against the conductive support plate. The ground trace and the dimpled pad may form a return path to ground for the resonating element. The dimpled pad may occupy less height within the device than other structures such as metal springs.

Abstract: A radio frequency system package may include waveguides and loading blocks. The loading blocks may include dielectric material having a high dielectric constant between 13 and 20. Additionally, the loading blocks may be made of mold, epoxy, or the like material, and the loading blocks may fit into a region cut out of the waveguides. Moreover, the loading blocks may lower the cut-off frequency for wireless communication otherwise provided by the waveguides without the loading blocks (e.g., 28 GHz). In particular, the loading blocks may facilitate communication in low mmWave frequencies, such as 24 GHz.

Abstract: An electronic device may be provided with a sidewall and an antenna module pressed against an interior surface of the sidewall. The module may include a phased antenna array. The sidewall may have apertures aligned with respective antenna in the array. The antennas may convey radio-frequency signals in first and second frequency bands greater than 10 GHz and with vertical and horizontal polarizations. Each aperture may include a corresponding cavity with non-linear cavity walls. The antennas may excite resonant cavity modes of the cavities that cause the cavities to radiate the radio-frequency signals as waveguide radiators. At the same time, the apertures may form a smooth impedance transition between the antennas and free space for the radio-frequency signals of both the horizontal and vertical polarizations.

Abstract: An electronic device may be provided with a conductive sidewall. An aperture may be formed in the sidewall. The sidewall may have a cavity that extends from the aperture towards the interior of the device. The cavity may be filled with an injection-molded plastic substrate. A dielectric block having a dielectric constant greater than that of the injection-molded plastic substrate and the antenna layers may be embedded in the injection-molded plastic substrate. The dielectric block may at least partially overlap an antenna. The antenna may convey radio-frequency signals at a frequency greater than 10 GHz through the cavity, the dielectric block, the injection-molded plastic substrate, and the aperture. The dielectric block may increase the effective dielectric constant of the cavity, allowing the antenna to cover relatively low frequencies without increasing the size of the aperture.

Abstract: An electronic device may be provided with a conductive sidewall. An aperture may be formed in the sidewall. The sidewall may have a cavity that extends from the aperture towards the interior of the device. The cavity may be filled with an injection-molded plastic substrate. A dielectric block having a dielectric constant greater than that of the injection-molded plastic substrate and the antenna layers may be embedded in the injection-molded plastic substrate. The dielectric block may at least partially overlap an antenna. The antenna may convey radio-frequency signals at a frequency greater than 10 GHz through the cavity, the dielectric block, the injection-molded plastic substrate, and the aperture. The dielectric block may increase the effective dielectric constant of the cavity, allowing the antenna to cover relatively low frequencies without increasing the size of the aperture.

Abstract: An electronic device may be provided with a conductive sidewall. An aperture may be formed in the sidewall. The sidewall may have a cavity that extends from the aperture towards the interior of the device. The cavity may be filled with an injection-molded plastic substrate. A dielectric block having a dielectric constant greater than that of the injection-molded plastic substrate and the antenna layers may be embedded in the injection-molded plastic substrate. The dielectric block may at least partially overlap an antenna. The antenna may convey radio-frequency signals at a frequency greater than 10 GHz through the cavity, the dielectric block, the injection-molded plastic substrate, and the aperture. The dielectric block may increase the effective dielectric constant of the cavity, allowing the antenna to cover relatively low frequencies without increasing the size of the aperture.

Abstract: An electronic device may be provided with a sidewall and an antenna module pressed against an interior surface of the sidewall. The module may include a phased antenna array. The sidewall may have apertures aligned with respective antenna in the array. The antennas may convey radio-frequency signals in first and second frequency bands greater than 10 GHz and with vertical and horizontal polarizations. Each aperture may include a corresponding cavity with non-linear cavity walls. The antennas may excite resonant cavity modes of the cavities that cause the cavities to radiate the radio-frequency signals as waveguide radiators. At the same time, the apertures may form a smooth impedance transition between the antennas and free space for the radio-frequency signals of both the horizontal and vertical polarizations.