Abstract: An inverted-F antenna is provided that has a resonating element arm and a ground element. A shorting branch of the resonating element arm shorts the resonating element arm to the ground element. An antenna feed that receives a transmission line is coupled to the resonating element arm and the ground element. One or more impedance discontinuity structures are formed along the resonating element arm at locations that are between the shorting branch and the antenna feed. The impedance discontinuity structures may include shorting structures and capacitance discontinuity structures. The impedance discontinuity structures may be formed by off-axis vertical conductors such as vias that pass through a dielectric layer separating the antenna resonating element arm from the ground element. Capacitance discontinuity structures may be formed from hollowed portions of the dielectric or other dielectric portions with a dielectric constant that differs from that of the dielectric layer.

Abstract: An antenna may be formed from conductive regions that define a gap that is bridged by shunt inductors. The inductors may have equal inductances and may be located equidistant from each other to form a scatter-type antenna structure. The inductors may also have unequal inductances and may be located along the length of the gap with unequal inductor-to-inductor spacings, thereby creating a decreasing shunt inductance at increasing distances from a feed for the antenna. This type of antenna structure functions as a horn-type antenna. One or more scatter-type antenna structures may be cascaded to form a multiband antenna. Antenna gaps may be formed in conductive device housings.

Abstract: Antennas for electronic devices such as portable computers are provided. An antenna may be formed from a conductive cavity and an antenna probe that serves as an antenna feed. The conductive cavity may have the shape of a quartered rectangular cavity and may have first and second side walls, top and bottom walls, and first and second openings. The first and second openings may be planar in shape and may meet at a right angle along an axis. The antenna probe may be disposed along the axis. The axis at which the first and second openings of the cavity meet may be located at the corner of an electronic device housing. The portable computer may have upper and lower housing portions that meet at a gasket. The gasket may be placed adjacent to the cavity face openings so that radio-frequency signals may enter and exit the cavity through the gasket.

Abstract: Antennas for electronic devices are provided. First and second antennas may be mounted within an electronic device. Free-space coupling between the first and second antennas may give rise to interference. The first and second antennas may be coupled to a global ground. The global ground may be formed using a conductive member in the electronic device such as a conductive frame member. Signals that pass between the antennas through the global ground may serve as canceling signals that reduce the magnitude of free-space interference signals and thereby improve antenna isolation. The antennas may be coupled to the global ground using electrical paths or through near-field electromagnetic coupling. Coupling efficiency to the global ground may be enhanced by configuring the conductive traces of one or both of the antennas to form a resonant circuit.

Abstract: Antennas for electronic devices such as portable computers are provided. An antenna may have a dipole structure in which one antenna element serves as a matching element and another antenna element serves as a radiating element. The antenna elements may be mounted on a substrate. The substrate may be mounted on a support structure that is attached to a grounding plate. The grounding plate may be grounded to a conductive housing portion of a portable computer. The antenna may be mounted within the conductive housing in the vicinity of an opening in the housing. The opening may be a slot opening that is used to accommodate optical disks or other storage media. Radio-frequency signals for the antenna may pass through the opening.

Abstract: A wireless communication method and antenna system for determining the direction of arrival (DOA) of received signals in azimuth and elevation, (i.e., in three dimensions), to form a beam for transmitting and receiving signals. The system includes two antenna arrays, each having a plurality of antenna elements, two first stage multi-mode-port matrices, at least one second stage multi-mode-port matrix, an azimuth phase detector, an elevation amplitude detector, a plurality of phase shifters and a transceiver. The antenna arrays and the first stage multi-mode-port matrices form a plurality of orthogonal omni-directional modes. Each of the modes has a characteristic phase set. Two of the modes' phases are used to determine DOA in azimuth. The second stage multi-mode-port matrix forms a sum-mode and a difference-mode used to determine the DOA of the received signals in elevation. A beam is formed in the direction of the received signals by adjusting the phase shifters.

Abstract: An antenna may be formed from conductive regions that define a gap that is bridged by shunt inductors. The inductors may have equal inductances and may be located equidistant from each other to form a scatter-type antenna structure. The inductors may also have unequal inductances and may be located along the length of the gap with unequal inductor-to-inductor spacings, thereby creating a decreasing shunt inductance at increasing distances from a feed for the antenna. This type of antenna structure functions as a horn-type antenna. One or more scatter-type antenna structures may be cascaded to form a multiband antenna. Antenna gaps may be formed in conductive device housings.

Abstract: An antenna assembly includes at least two active or main radiating omni-directional antenna elements arranged with at least one beam control or passive antenna element used as a reflector. The beam control antenna element(s) may have multiple reactance elements that can electrically terminate it to adjust the input or output beam pattern(s) produced by the combination of the active antenna elements and the beam control antenna element(s). More specifically, the beam control antenna element(s) may be coupled to different terminating reactances to change beam characteristics, such as the directivity and angular beam width. Processing may be employed to select which terminating reactance to use. Consequently, the radiator pattern of the antenna can be more easily directed towards a specific target receiver/transmitter, reduce signal-to-noise interference levels, and/or increase gain.

Abstract: Wireless portable electronic devices such as laptop computers are provided with antennas and radio-frequency transceiver circuitry. Antenna structures and transceiver circuitry may be provided within a clutch barrel in a laptop computer. The clutch barrel may have a dielectric cover. Antenna elements may be mounted within the clutch barrel cover on an antenna support structure. The antenna support structure may be mounted to a metal housing frame. The metal housing frame may have a tab-shaped extension that serves as a heat sink. The heat sink may draw heat away from the transceiver circuitry. The transceiver circuitry may be coupled to the antenna using a radio-frequency transmission line path that contains microstrip transmission lines or coaxial cable transmission lines. The transceiver circuitry may be coupled to logic circuitry on a laptop computer motherboard using a digital data communications path.

Abstract: Wireless portable electronic devices such as laptop computers are provided with antennas. An antenna may be provided within a clutch barrel in a laptop computer. The clutch barrel may have a dielectric cover. Antenna elements may be mounted within the clutch barrel cover on an antenna support structure. There may be two or more antenna elements mounted to the antenna support structure. These antenna elements may be of different types. A first antenna element for the clutch barrel antenna may be formed from a dual band antenna element having a closed slot and an open slot. A second antenna element for the clutch barrel antenna may be formed from a dual band antenna element of a hybrid type having a planar resonating element arm and a slot resonating element. Flex circuit structures may be used in implanting the first and second antenna elements for the clutch barrel antenna.

Abstract: Wireless portable electronic devices such as laptop computers are provided with cavity-backed monopole antennas. A wireless device may have a housing. Conductive portions of the housing such as a conductive outer metal layer and internal frame structures may form a cavity having conductive walls. An antenna resonating element structure may be formed from monopole antenna resonating element arms of dissimilar lengths. One of the arms may be straight and another of the arms may be implemented using a meandering path. The antenna resonating element may be mounted over the cavity to form a cavity-backed monopole antenna. A display within the device may be covered by a cover glass. An opaque bezel region around the periphery of the cover glass may cover the antenna and block it from view. The antenna resonating element arms may run parallel to the longitudinal axis of the cavity.

Abstract: A satellite communication subscriber device includes a smart antenna for generating antenna beams for receiving signals from at least one satellite, and a receiver. The receiver includes a quality metric module for calculating a quality metric on the signals received by each antenna beam. A beam selector is coupled to the smart antenna for selecting the antenna beams. An antenna steering algorithm module runs an antenna steering algorithm for operating the beam selector for scanning the antenna beams, receiving the calculated quality metrics from the receiver for each scanned antenna beam, and comparing the calculated quality metrics. The algorithm selects one of the scanned antenna beams based upon the comparing for continuing to receive signals from the at least one satellite.

Abstract: An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.

Abstract: Antenna window structures and antennas are provided for electronic devices. The electronic devices may be laptop computers or other devices that have conductive housings. Antenna windows can be formed from dielectric members. The dielectric members can have elastomeric properties. An antenna may be mounted inside a conductive housing beneath a dielectric member. The antenna can be formed from a parallel plate waveguide structure. The parallel plate waveguide structure may have a ground plate and a radiator plate and may have dielectric material between the ground and radiator plates. The ground plate can have a primary ground plate portion and a ground strip. The ground strip may reflect radio-frequency signals so that they travel through the dielectric member. The antenna may handle radio-frequency antenna signals in one or more communications bands. The radio-frequency antenna signals pass through the dielectric member.

Abstract: Slot antennas are provided for electronic devices such as portable electronic devices. The slot antennas may have a dielectric-filled slot that is formed in a ground plane element. The ground plane element may be formed from part of a conductive device housing. The slot may have one or more holes at its ends. The holes may affect the impedance characteristics of the slot antennas so that the length of the slot antennas may be reduced. For example, the holes can be used to synthesize the impedance of the slot antennas so that the slot antennas have a resonant frequency that is different from their natural resonant frequency. The holes may affect the impedance of the slot antennas in multiple radio-frequency bands.

Abstract: Dual slot antennas are provided for portable electronic devices such as handheld electronic devices. A dual slot antenna may have an open slot that has an open end that is not encircled by conductive material and may have a closed slot in which each end is surrounded by conductor. The closed and open slots may have portions that run parallel to each other. The antenna may be fed using feed terminals that bridge the closed and open slots in the vicinity of the portions of the slots that run parallel to each other. The slots may have portions that are angled with respect to each other. An end portion of one of the slots may be bent and widened for impedance matching and broadened bandwidth. Other portions of the slots may also be angled with respect to their main longitudinal axes.

Abstract: Antenna window structures and antennas for electronic devices such as portable electronic devices are provided. The electronic devices may be computers or other devices that have conductive housings. Antenna windows may be formed from one or more slots in the conductive housings. The slots may be filled with air or a solid dielectric such as epoxy. There may be a number of parallel slots in a given antenna window, each having a width that is sufficiently narrow to make the antenna window invisible or unnoticeable to the naked eye under normal observation. An antenna may be formed within an electronic device adjacent to an antenna window. The antenna may handle radio-frequency antenna signals in one or more communications bands. The radio-frequency antenna signals may pass through the slots in the antenna window.

Abstract: An antenna may be formed from conductive regions that define a gap that is bridged by shunt inductors. The inductors may have equal inductances and may be located equidistant from each other to form a scatter-type antenna structure. The inductors may also have unequal inductances and may be located along the length of the gap with unequal inductor-to-inductor spacings, thereby creating a decreasing shunt inductance at increasing distances from a feed for the antenna. This type of antenna structure functions as a horn-type antenna. One or more scatter-type antenna structures may be cascaded to form a multiband antenna. Antenna gaps may be formed in conductive device housings.

Abstract: Microslot antennas may be provided for electronic devices such as portable electronic devices. The microslot antennas may have dielectric-filled microslots that are formed in a ground plane element. The ground plane element may be formed from part of a conductive device housing. The microslots may be narrow enough that they are not readily noticeable to the naked eye. The microslots may have lengths that allow the microslot antenna to provide antenna coverage in one or more communications bands. A first group of the microslots may be used to provide coverage in a first communications band and a second group of the microslots may be used to provide coverage in a second communications band.

Abstract: Electronic devices and antennas for electronic devices are provided. The antennas may have ground plane elements with dielectric-filled openings. The dielectric-filled openings may be configured to form one or more rectangular slots. The antennas may be fed using transmission lines having first and second conductors. The first conductor of a given transmission line may be coupled to the ground plane element on one side of the slots. The second conductor of the transmission line may be coupled to a planar conductive element. The planar conductive element may couple to the ground plane element on the other side of the slots. The slots may be separated by a portion of the ground plane element. The planar conductive element may bridge at least one of the slots and may overlap the portion of the ground plane element that separates the slots without electrically contacting that portion of the ground plane element.