A communication device includes a first near field communication (NFC) antenna configured to have a first resonance frequency, and a metal chassis forming part of an outer surface of the communication device. The metal chassis forms an auxiliary antenna, where the auxiliary antenna is configured to be powered by the first NFC antenna by electromagnetic induction and is also configured to have a resonance frequency substantially equal to the first resonance frequency.

An antenna device as described herein includes a first metal layer and a second metal layer. The second metal layer is spaced apart from the first metal layer. The first metal layer includes an opening through which to transmit RF (Radio Frequency) energy to the second metal layer. The second metal layer is operable to reflect the RF energy received through the opening back to a surface of the first metal layer. The first metal layer is operable to reflect the RF energy (received from the reflection off the second metal layer) in a direction past the second metal layer through a communication medium. The surface area of the first metal layer is sufficiently larger than a surface area of the second metal layer to reflect the RF energy past the second metal layer into the communication medium. This ensures that the antenna device operates in a reflective mode as opposed to a resonant mode, resulting in high gain.

An RFID antenna assembly configured to be energized with a carrier signal is disclosed. The RFID antenna assembly includes an inductive component including a loop antenna assembly, at least one capacitive component coupled to the inductive component, and an eddy current trap positioned a predetermined distance from the loop antenna assembly.

An RFID antenna assembly configured to be energized with a carrier signal is disclosed. The RFID antenna assembly includes an inductive component including a loop antenna assembly, at least one capacitive component coupled to the inductive component, and an eddy current trap positioned a predetermined distance from the loop antenna assembly.

A device includes a plurality of antennas, including one or more active antennas, the antennas being configured in one of a plurality of possible configurations to achieve operation in WAN, LTE, WiFi, or WiMax bands, or a combination thereof. In some embodiments, a passive antenna is utilized with lumped loading to fix the antenna tuning state. A primary and auxiliary radiator can be included in the device and configured for WAN/LTE bands, while additional antennas can be incorporated for WiFi and WiMax bands. Various antenna configurations incorporate the antenna having multiple coupled regions.

Apparatus and methods for reconfigurable antenna systems are provided herein. In certain configurations, an antenna system includes an antenna element, a tuning conductor adjacent to and spaced apart from the antenna element, and a switch electrically connected between the tuning conductor and a reference voltage, such as ground. The tuning conductor is operable to load the antenna element, and the switch selectively connects the tuning conductor to the reference voltage to provide tuning to the antenna element.

An antenna includes feed pads; a radiating portion disposed on one side of the feed pads and spaced apart from the feed pads, the radiating portion being constituted by a single conductor plate; and a ground part disposed on an opposite side of the feed pads from the radiating portion; wherein each of the feed pads has a polygonal shape.

A microstrip patch antenna comprising: a unit cell comprising: a plurality of layers comprising: a first laminate comprising one or more horizontal polarization feed lines and one or more vertical polarization feed lines, a second laminate comprising a radiating square patch, and a third laminate comprising a parasitic patch; and a ground plane comprising one or more polarization slots. A differential feed antenna comprising: a balun; a plurality of feed lines; and one or more polarization ports configured to excite at a plurality of locations.

Among other things, a reconfigurable antenna array (RAA) includes individual pattern reconfigurable antennas (PRA). Each of the PRAs has (a) an antenna, (b) components controllable to generate and effect any of two or more modes of the PRA, the modes having respectively different steered radiation patterns, and (c) inputs to receive drive signals for the antenna and control signals for the controllable components. Control circuitry has outputs coupled to the inputs of the PRAs to drive the antennas of the PRAs to form an array beam having an array peak in a particular direction and at the same time to deliver control signals for the controllable components to effect a selected mode of each of the PRAs for which the steered radiation pattern has a peak in the particular direction of the array beam and has one or more nulls in the directions of one or more of the side-lobes of the array beam.

A magnetic field focusing assembly includes a magnetic field generating device configured to generate a magnetic field, and a split ring resonator assembly configured to be magnetically coupled to the magnetic field generating device and configured to focus the magnetic field produced by the magnetic field generating device.