Abstract:
Electronic devices may include radio-frequency transceiver circuitry and antenna structures. The antenna structures may form a dual arm inverted-F antenna and a monopole antenna sharing a common antenna ground. The antenna structures may have three ports. A first antenna port may be coupled to an inverted-F antenna resonating element at a first location and a second antenna port may be coupled to the inverted-F antenna resonating element at a second location. A third antenna port may be coupled to the monopole antenna. Tunable circuitry can be used to tune the antenna structures. An adjustable capacitor may be coupled to the first port to tune the inverted-F antenna. An additional adjustable capacitor may be coupled to the third port to tune the monopole antenna. Transceiver circuitry for supporting wireless local area network communications, satellite navigation system communications, and cellular communications may be coupled to the first, second, and third antenna ports.
Abstract:
Metal housing walls may form an antenna cavity. Antenna structures may be formed from metal traces mounted on a carrier in the antenna cavity. The antenna structures may form an array of antennas such as an array of planar inverted-F antennas. The housing may have an inner cavity wall such as a circular inner cavity wall. The planar inverted-F antennas may lie between the inner cavity wall and the metal walls of the housing. Each planar inverted-F antenna may have an associated parasitic antenna resonating element. The planar inverted-F antennas may be configured to resonate in upper and lower frequency bands. The parasitic elements may each extend inwardly from the metal walls and may broaden the frequency response of the planar inverted-F antennas in the lower frequency band. Parasitic elements may be used to isolate antennas from each other.
Abstract:
Electronic devices may be provided that have antenna traces. The antenna traces may be configured to form an inductive loop that serves as a near field communications antenna. A layer of ferrite may be provided to reduce interference between the antenna and internal device components. The layer of ferrite and the antenna traces may be deposited on a common substrate such as a layer of polymer or a dielectric electronic device housing. A protective layer of polymer may be used to form a coating on the layer of ferrite. Ferrite may be formed on the same side of a substrate as the antenna traces or may be formed on an opposing side of the substrate.
Abstract:
An electronic device may be provided with wireless circuitry. The wireless circuitry may include wireless transceiver circuitry that transmits signals towards an antenna. A signal path may carry the transmitted signals to the antenna. Reflected signals from the antenna may be carried along the signal path towards the transceiver circuitry. Coupler circuitry may include a forward coupler that taps the transmitted signals, a first reverse coupler that taps the reflected signals from the antenna, and a second reverse coupler that taps the reflected signals that have passed through the first reverse coupler. Analog processing circuitry and digital processing circuitry may be used to produce an impedance measurement from the tapped signals from the coupler circuitry. The analog processing circuitry may include analog signal mixers, low pass filters, and analog-to-digital converter circuitry.
Abstract:
An electronic device may have wireless circuitry with antennas. An antenna may have an inverted-F antenna resonating element, an antenna ground, and other resonating element structures. A tip of the antenna resonating element and the antenna ground may be separated by a peripheral housing gap filled with plastic. The antenna may be sensitive to capacitance changes induced by the presence of a user's hand overlapping the gap or other portions of the antenna. A hand capacitance sensing electrode may be mounted in the plastic of the gap or elsewhere in the vicinity of the antenna. A transmission line may couple the hand capacitance sensing electrode to the antenna to retune the antenna in the event that the user's hand overlaps the antenna.
Abstract:
Electronic devices may include radio-frequency transceiver circuitry and antenna structures. The antenna structures may form a dual arm inverted-F antenna and an additional antenna such as a monopole antenna sharing a common antenna ground. The antenna structures may have three ports. A first antenna port may be coupled to an inverted-F antenna resonating element at a first location and a second antenna port may be coupled to the inverted-F antenna resonating element at a second location. A third antenna port may be coupled to the additional antenna. An adjustable component may be coupled to the first antenna port to tune the inverted-F antenna. The inverted-F antenna may be near-field coupled to the additional antenna so that the inverted-F antenna may serve as a tunable parasitic antenna resonating element that tunes the additional antenna.
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 antennas that are tuned, adjustable impedance matching circuitry, antenna port selection circuitry, and adjustable transceiver circuitry. Wireless circuit adjustments may be made by ascertaining a current usage scenario for the electronic device based on sensor data, information from cellular base station equipment or other external equipment, signal-to-noise ratio information or other signal information, antenna impedance measurements, and other information about the operation of the electronic device.
Abstract:
An electronic device may have radio-frequency transceiver circuitry for transmitting and receiving antenna signals using an antenna. The antenna may be formed within a connector port in the electronic device or may be formed on an external cable that is coupled to the connector port. The antenna may have an antenna resonating element that is formed from a signal wire in the external cable or that is formed from a metal structure mounted to the external cable. The radio-frequency transceiver circuitry may be directly coupled to the antenna resonating element using springs or other direct coupling mechanisms or may be coupled to the antenna resonating element using a coupling structure. The coupling structure may include a capacitor electrode, an inductor, or other structures for coupling to the antenna resonating element by electromagnetic near-field coupling.
Abstract:
An electronic device has antennas formed from cavity antenna structures. The electronic device may have a metal housing. The metal housing may have an upper housing in which a component such as a display is mounted and a lower housing in which a component such as a keyboard is mounted. Hinges may be used to mount the upper housing to the lower housing for rotation about a rotational axis. Cavity antennas may be formed in a clutch barrel region located between the hinges and running along the rotational axis. A flexible printed circuit may be formed between the cavity antennas. Each cavity antenna may have a first end that is adjacent to one of the hinges and a second end that is adjacent to the flexible printed circuit. Cavity walls for the cavity antennas may be formed from metal housing structures such as metal portions of the lower housing.
Abstract:
A wireless electronic device may contain at least one adjustable antenna tuning element for use in tuning the operating frequency range of the device. The antenna tuning element may include radio-frequency switches, continuously/semi-continuously adjustable components such as tunable resistors, inductors, and capacitors, and other load circuits that provide desired impedance characteristics. A test system that is used for performing passive radio-frequency (RF) testing on antenna tuning elements in partially assembled devices is provided. The test system may include an RF tester and a test host. The tester may be used to gather scattering parameter measurements from the antenna tuning element. The test host may be used to ensure that power and appropriate control signals are being supplied to the antenna tuning element so that the antenna tuning element is placed in desired tuning states during testing.