Abstract: A flex circuit may have test structures and antenna structures. The test structures may include test capacitors and transmission lines. The performance of the test structures may be measured using test equipment. Pass/fail criteria may be applied to the flex circuit based on the measured values. If the flex circuit is a failing circuit, flex circuit manufacturing settings may be adjusted. The performance of a radio-frequency (RF) cable may also be measured using the test equipment. Sample portions of the RF cable may be obtained and measured. Pass/fail criteria may be applied to the RF cable based on measured cable loss values. If the RF cable is a failing cable, RF cable manufacturing settings may be adjusted. Antenna structures associated with passing flex circuits and RF cable segments associated with passing sample RF cable segments may be incorporated into a wireless device during production device assembly.

Abstract: Electronic devices such as handheld devices may have wireless communications circuitry. The wireless communications circuitry may include a broadband antenna and circuitry that covers multiple communications bands. The broadband antenna may be formed from a parallel-fed dipole. The antenna may have first and second antenna resonating element regions on opposing sides of a slot. The slot may be an open slot that has one open end and one closed end. The slot may be formed from an opening in conductive housing structures in a conductive housing for an electronic device. The conductive housing structures may include sidewall structures, rear housing wall structures, and other conductive structures. The antenna may have a feed with a feed line that crosses the slot. An interposed dielectric substrate member may separate the feed line from the conductive structures. The feed line may have sections with different widths to minimize feed line length.

Abstract: Electronic devices are provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry and antenna structures. A display may be mounted on a front face of an electronic device. A conductive member such as a bezel may surround the display. Internal housing support structures such as a metal midplate member may be used to support the display. The midplate member may be connected between opposing edges of the bezel. The antenna structures may include an antenna formed from part of the midplate member and part of the bezel. Antenna image currents in the midplate member may be blocked by slots in the midplate member. The slots may be located adjacent to the antenna and may ensure that the antenna emits radio-frequency signals in a desired pattern. The slots may be angled and segmented.

Abstract: A method of manufacture for a portable computing device is described. In particular, methods and apparatus for assessing a quality of weld joints used to connect one or more components of the portable computing device are described. The weld joints can include one or more weld points. At a weld check station, using a vector network analyzer, a test signal generated can be passed through the weld joint and a response signal can be measured. The measured characteristics can be used to assess a quality of the weld joint. In one embodiment, the vector network analyzer can be used to generate a number of high frequency test signals that are passed through the weld to perform a time domain reflectometry measurement where the weld joint can be accepted or rejected based upon the measurement.

Abstract: A wireless electronic device may serve as a device under test in a test system. The test system may include an array of over-the-air antennas that can be used in performing over-the-air wireless tests on the device under test (DUT). A channel model may be used in modeling a multiple-input-multiple-output (MIMO) channel between a multi-antenna wireless base station and a multi-antenna DUT. The test system may be configured to perform over-the-air tests that emulate the channel model. A design and analysis tool may be used to identify an optimum over-the-air test system setup. The tool may be used in converting a geometric model to a stochastic model for performing conducted tests. The tool may be used in converting a stochastic model to a geometric model and then further convert the geometric model to an over-the-air emulated stochastic model. The over-the-air emulated stochastic model may be used in performing conducted tests.

Abstract: Apparatus and methods for authenticating and granting a client device (e.g., cellular telephone) access to a network. In one embodiment, a network service provider such as a cellular telephone company may distribute user access (e.g., Universal Subscriber Identity Module or “USIM”) credentials to a services manager via a USIM vendor. The services manager may maintain a list of authorized users. A user at a client may authenticate to the services manager. Once authenticated, the services manager may provide the user with a set of USIM credentials. When the user desires to use wireless network services, the user equipment may establish a wireless link between the user equipment and the network service provider. During authentication operations, the user equipment may use the USIM credentials to authenticate to the network service provider. Following successful authentication, the network service provider may provide the user equipment with wireless services.

Abstract: An electronic device such as a portable electronic device has wireless communications circuitry. Antennas in the electronic device may be used in transmitting radio-frequency antenna signals. A coupler and antenna signal phase and magnitude measurement circuitry may be used to determine when external objects are in the vicinity of the antenna by making antenna impedance measurements. In-band and out-of-band phase and magnitude signal measurements may be made in determining whether external objects are present. Additional sensors such as motion sensors, light and heat sensors, acoustic and electrical sensors may produce data that can be combined with the proximity data gathered using the antenna-based proximity sensor. In response to detecting that an external object such as a user's body is within a given distance of the antenna, the electronic device may reduce transmit powers, switch antennas, steer a phased antenna array, switch communications protocols, or take other actions.

Abstract: An antenna resonating element may be mounted in an antenna cavity. The antenna resonating element may have a printed circuit board substrate with a patterned metal layer. Components may be soldered to the antenna resonating element using solder with a given melting point before soldering the antenna resonating element the antenna cavity using solder with a lower melting point. Solder widow openings may be formed in the antenna resonating element and antenna cavity to allow for application of solder paste. Engagement features and alignment structures may be used to align the antenna resonating element relative to the antenna cavity. The antenna cavity may have a curved opening. The printed circuit board substrate may be bent to the shape of the curved opening before soldering components to the printed circuit board. An elastomeric fixture may be used to hold the antenna resonating element to the cavity during soldering.

Abstract: Electronic devices are provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry and antenna structures. An inverted-F antenna may have first and second short circuit legs and a feed leg. The first and second short circuit legs and the feed leg may be connected to a folded antenna resonating element arm. The antenna resonating element arm and the first short circuit leg may be formed from portions of a conductive electronic device bezel. The folded antenna resonating element arm may have a bend. The bezel may have a gap that is located at the bend. Part of the folded resonating element arm may be formed from a conductive trace on a dielectric member. A spring may be used in connecting the conductive trace to the electronic device bezel portion of the antenna resonating element arm.

Abstract: Handheld electronic devices are provided that contain wireless communications circuitry having at least first and second antennas. An antenna isolation element reduces signal interference between the antennas, so that the antennas may be used in close proximity to each other. A planar ground element may be used as a ground by the first and second antennas. The first antenna may be formed using. a hybrid planar-inverted-F and slot arrangement in which a planar resonating element is located above a rectangular slot in the planar ground element. The second antenna may be formed from an L-shaped strip. The planar resonating element of the first antenna may have first and second arms. The first arm may resonate at a common frequency with the second antenna and may serve as the isolation element. The second arm may resonate at approximately the same frequency as the slot portion of the hybrid antenna.

Abstract: A handheld electronic device may be provided that contains wireless communications circuitry. The handheld electronic device may have a housing and a display. The display may be attached to the housing using a conductive bezel. The handheld electronic device may have one or more antennas for supporting wireless communications. A ground plane in the handheld electronic device may serve as ground for one or more of the antennas. The ground plane and bezel may define a opening. A rectangular slot antenna or other suitable slot antenna may be formed from or within the opening. One or more antenna resonating elements may be formed above the slot. An electrical switch that bridges the slot may be used to modify the perimeter of the slot so as to tune the communications bands of the handheld electronic device.

Abstract: Electronic devices are provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry and antenna structures. A parallel-fed loop antenna may be formed from portions of an electronic device bezel and a ground plane. The antenna may operate in multiple communications bands. An impedance matching circuit for the antenna may be formed from a parallel-connected inductive element and a series-connected capacitive element. The bezel may surround a peripheral portion of a display that is mounted to the front of an electronic device. The bezel may contain a gap. Antenna feed terminals for the antenna may be located on opposing sides of the gap. The inductive element may bridge the gap and the antenna feed terminals. The capacitive element may be connected in series between one of the antenna feed terminals and a conductor in a transmission line located between the transceiver circuitry and the antenna.

Abstract: Electronic devices are provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry and antenna structures. A parallel-fed loop antenna may be formed from portions of an electronic device bezel and a ground plane. The antenna may operate in multiple communications bands. An impedance matching circuit for the antenna may be formed from a parallel-connected inductive element and a series-connected capacitive element. The bezel may surround a peripheral portion of a display that is mounted to the front of an electronic device. The bezel may contain a gap. Antenna feed terminals for the antenna may be located on opposing sides of the gap. The inductive element may bridge the gap and the antenna feed terminals. The capacitive element may be connected in series between one of the antenna feed terminals and a conductor in a transmission line located between the transceiver circuitry and the antenna.

Abstract: A test system for testing multiple-input and multiple-output (MIMO) systems is provided. The test system may convey signals bidirectionally between two test chambers. Each test chamber may be lined with foam to minimize electromagnetic reflections. Each test chamber may include structure three-dimensional array of test antennas. The test antennas may be mounted in a sphere using an antenna mounting structure. The antenna mounting structure may include multiple rings of different sizes. Test antennas may be embedded in the inner walls of the antenna mounting structure. There may be multiple receiving antennas located in each test chamber. One test chamber may include a device under test inside an array of test antennas and another test chamber may include base station antennas inside another array of test antennas. Signals may be conveyed between the test chambers using channel emulators.

Abstract: A handheld electronic device may be provided that contains wireless communications circuitry. The handheld electronic device may have a housing and a display. The display may be attached to the housing a conductive bezel. The handheld electronic device may have one or more antennas for supporting wireless communications. A ground plane in the handheld electronic device may serve as ground for one or more of the antennas. The ground plane and bezel may define a opening. A rectangular slot antenna or other suitable slot antenna may be formed from or within the opening. One or more antenna resonating elements may be formed above the slot. An electrical switch that bridges the slot may be used to modify the perimeter of the slot so as to tune the communications bands of the handheld electronic device.

Abstract: A handheld electronic device may be provided that contains a conductive housing and other conductive elements. The conductive elements may form an antenna ground plane. One or more antennas for the handheld electronic device may be formed from the ground plane and one or more associated antenna resonating elements. Transceiver circuitry may be connected to the resonating elements by transmission lines such as coaxial cables. Ferrules may be crimped to the coaxial cables. A bracket with extending members may be crimped over the ferrules to ground the coaxial cables to the housing and other conductive elements in the ground plane. The ground plane may contain an antenna slot. A dock connector and flex circuit may overlap the slot in a way that does not affect the resonant frequency of the slot. Electrical components may be isolated from the antenna using isolation elements such as inductors and resistors.

Abstract: An electronic device may have a cavity antenna. The cavity antenna may have a logo-shaped dielectric window. An antenna resonating element for the cavity antenna may be formed from conductive traces on a printed circuit board. An antenna resonating element may be formed from the traces. The antenna resonating element may be mounted on an antenna support structure. A conductive cavity structure for the cavity antenna may have a planar lip that is mounted flush with an interior surface of a conductive housing wall. The cavity structure may have more than one depth. Shallower planar portions of the cavity structure may lie in a plane. The antenna resonating element may be located between the plane of the shallow cavity walls and an external surface of the conductive housing wall.

Abstract: A handheld electronic device may be provided that contains wireless communications circuitry. The handheld electronic device may have a housing and a display. The display may be attached to the housing a conductive bezel. The handheld electronic device may have one or more antennas for supporting wireless communications. A ground plane in the handheld electronic device may serve as ground for one or more of the antennas. The ground plane and bezel may define a opening. A rectangular slot antenna or other suitable slot antenna may be formed from or within the opening. One or more antenna resonating elements may be formed above the slot. An electrical switch that bridges the slot may be used to modify the perimeter of the slot so as to tune the communications bands of the handheld electronic device.

Abstract: An electronic device may have a housing with conductive housing walls. A dielectric antenna window may be formed in an opening in one of the conductive housing walls. A dielectric logo may form the dielectric antenna window. A dielectric support structure may have an outline that matches the dielectric logo. An antenna resonating element for an antenna may be formed on the dielectric support structure. An antenna cavity for the antenna may be formed by a conductive cavity structure. A pattern of voids in the dielectric support structure may reduce dielectric loading for the antenna. The conductive cavity structure may be formed from solderable plated metal. The conductive cavity structure may have a planar lip that is attached to the conductive housing walls using conductive adhesive. Rear wall portions of the conductive cavity structure may be oriented at a non-perpendicular non-zero angle with respect to the planar lip.

Abstract: Handheld electronic devices are provided that contain wireless communications circuitry having at least first and second antennas. An antenna isolation element reduces signal interference between the antennas, so that the antennas may be used in close proximity to each other. A planar ground element may be used as a ground by the first and second antennas. The first antenna may be formed using a hybrid planar-inverted-F and slot arrangement in which a planar resonating element is located above a rectangular slot in the planar ground element. The second antenna may be formed from an L-shaped strip. The planar resonating element of the first antenna may have first and second arms. The first arm may resonate at a common frequency with the second antenna and may serve as the isolation element. The second arm may resonate at approximately the same frequency as the slot portion of the hybrid antenna.