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 have wireless circuitry with antennas. An antenna resonating element arm for an antenna may be formed from peripheral conductive structures running along the edges of a device housing. The peripheral conductive structures may form housing sidewalls. A slot may be machined into a metal housing that separates the housing sidewalls from a planar rear housing portion that forms a ground for an antenna. The slot may be filled with plastic filler. A parasitic antenna resonating element arm that supports an antenna resonance at high band frequencies may be embedded within the plastic filler. The parasitic antenna resonating element may be formed from a portion of the planar rear housing portion.
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 have wireless circuitry with antennas. An antenna resonating element arm for an antenna may be formed from peripheral conductive structures running along the edges of a device housing. The peripheral conductive structures may form housing sidewalls. A slot may be machined into a metal housing that separates the housing sidewalls from a planar rear housing portion that forms a ground for an antenna. The slot may be filled with plastic filler. A parasitic antenna resonating element arm that supports an antenna resonance at high band frequencies may be embedded within the plastic filler. The parasitic antenna resonating element may be formed from a portion of the planar rear housing portion.
Abstract:
An electronic device may be provided with an antenna. The antenna may have an antenna resonating element and an antenna ground. The antenna resonating element may be formed from peripheral conductive housing structures. An audio jack or other connector may be mounted in an opening in the peripheral conductive housing structures. The audio jack may overlap the antenna ground. Contacts in the audio jack may be coupled to an interference mitigation circuit. The interference mitigation circuit may include capacitors coupled to the ground and inductors coupled between the contacts and the capacitors. Radio-frequency signal blocking inductors may be coupled between the interference mitigation circuit and respective ports in an audio circuit.
Abstract:
An electronic device may have wireless circuitry with antennas. An antenna resonating element arm for an antenna may be formed from peripheral conductive structures running along the edges of a device housing. The peripheral conductive structures may form housing sidewalls. A slot may be machined into a metal housing that separates the housing sidewalls from a planar rear housing portion that forms a ground for an antenna. The slot may be filled with plastic filler. A parasitic antenna resonating element arm that supports an antenna resonance at high band frequencies may be embedded within the plastic filler. The parasitic antenna resonating element may be formed from a portion of the planar rear housing portion.
Abstract:
An electronic device may be provided with an antenna. The antenna may have an antenna resonating element and an antenna ground. An adjustable inductor may be coupled between the antenna resonating element and the antenna ground. An antenna feed may have a positive feed terminal coupled to the antenna resonating element and a ground antenna feed coupled to the antenna ground. The adjustable inductor may have first and second inductors coupled to respective first and second ports of a switch. The switch may have a third port coupled to the antenna ground. A capacitor may have a first terminal coupled to ground and a second terminal coupled to the first inductor at the first port of the switch. An inductor may be coupled between the antenna resonating element and antenna ground at a location between the adjustable inductor and the antenna feed.
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 be provided with an antenna. The antenna may have an antenna resonating element and an antenna ground. The antenna resonating element may be formed from peripheral conductive housing structures. An audio jack or other connector may be mounted in an opening in the peripheral conductive housing structures. The audio jack may overlap the antenna ground. Contacts in the audio jack may be coupled to an interference mitigation circuit. The interference mitigation circuit may include capacitors coupled to the ground and inductors coupled between the contacts and the capacitors. Radio-frequency signal blocking inductors may be coupled between the interference mitigation circuit and respective ports in an audio circuit.
Abstract:
An electronic device may be provided with a housing. The housing may have a periphery that is surrounded by peripheral conductive structures such as a segmented peripheral metal member. A segment of the peripheral metal member may be separated from a ground by a slot. An antenna feed may have a positive antenna terminal coupled to the peripheral metal member and a ground terminal coupled to the ground and may feed both an inverted-F antenna structure that is formed from the peripheral metal member and the ground and a slot antenna structure that is formed from the slot. Control circuitry may tune the antenna by controlling adjustable components that are coupled to the peripheral metal member. The adjustable components may include adjustable inductors and adjustable capacitors.