Abstract:
An electronic device may have wireless circuitry with antennas. An antenna resonating element arm for an antenna may be formed from conductive housing structures running along the edges of a device. The antenna may have a pair of switchable return paths that bridge a slot between the antenna resonating element and an antenna ground. An adjustable component and a feed may be coupled in parallel across the slot. The adjustable component may switch a capacitor into use or out of use and the return paths may be selectively opened and closed to compensate for antenna loading due to the presence of external objects near the electronic device.
Abstract:
An electronic device may be provided with wireless circuitry. Control circuitry may be used to adjust the wireless circuitry. The wireless circuitry may include an antenna that is tuned using tunable components. The control circuitry may gather information on the current operating mode of the. electronic device, sensor data from a proximity sensor, accelerometer, microphone, and other sensors, antenna impedance information for the antenna, and information on the use of connectors in the electronic device. Based on this gathered data, the control circuitry can adjust the tunable components to compensate for antenna detuning due to loading from nearby external objects, may adjust transmit power levels, and may make other wireless circuit adjustments.
Abstract:
An electronic device may have a conductive housing with an antenna window. Antenna structures may be mounted adjacent to the antenna window. The antenna structures may have a dielectric carrier. Patterned metal antenna traces may be formed on the surface of the dielectric carrier. A proximity sensor may be formed from a flexible printed circuit mounted on the dielectric carrier. The flexible printed circuit may have a tail that contains a transmission line for feeding the antenna structures. The transmission line may include a positive signal conductor that is maintained at a desired distance from the conductive housing using a polymer sheet. A portion of the antenna structures may protrude between a microphone and a camera module. Plastic camera module housing structures may have an inner surface coated with a shielding metal. A U-shaped conductive fabric layer may be used as a grounding structure.
Abstract:
An electronic device may have an antenna for providing coverage in wireless communications bands of interest. The wireless communications bands may include a communications band at a first frequency. The antenna may have a parasitic antenna resonating element that supports a low efficiency resonance. In response to operation of the electronic device in free space, the low efficiency resonance will be located at a second frequency that is greater than the first frequency. In response to operation of the electronic device in proximity to a user's body or other external object, the antenna will be loaded and the low efficiency resonance associated with the parasitic antenna resonating element will shift to the communications band at the first frequency. The antenna may include a resonating element formed on a flexible printed circuit or a dielectric carrier such as a plastic support structure.
Abstract:
An electronic device may have an antenna for providing coverage in wireless communications bands of interest such as a low frequency communications band, a middle frequency communications band, and a high frequency communications band. Slot structures in the antenna that might reduce efficiency in the high frequency communications band may be avoided by capacitively loading the antenna and omitting meandering paths in the antenna. A capacitor may be coupled between an antenna ground formed from a metal housing structure and an antenna resonating element having a curved shape that conforms to the shape of the edge of the electronic device. The capacitor may have interdigitated fingers and may be adjustable to tune the antenna. The antenna may transmit and receive radio-frequency signals through a display cover layer in a display and a dielectric antenna window portion of the housing.
Abstract:
Antenna structures for an antenna may be formed from a dielectric carrier with metal structures. The metal structures may be patterned to cover all sides of the dielectric carrier. The dielectric carrier may have a shape with six sides or other shape that creates a three-dimensional layout for the antenna structures. The antenna structures may have a tunable circuit that allows the antenna to be tuned. The tunable circuit may have first and second terminals coupled to one of the sides of the carrier. The metal structures may be configured to form an inverted-F antenna resonating element. Portions of the metal structures may form a first arm for an inverted-F antenna and portions of the metal structures may form a second arm for the inverted-F antenna. The antenna may operate in multiple communications bands. The tunable circuit may tune one band without significantly tuning other bands.