Short, dual-driven groundless antennas are provided. One of the antennas includes a tubular outer conductor, a tubular inner conductor, and an electrical connector that electrically connects an opposite end of the outer conductor to the exterior of the inner conductor. The inner conductor is longitudinally disposed within the hollow axial interior of the outer conductor such that an axial gap exists between the radially inner surface of the outer conductor and the radially outer surface of the inner conductor, and the inner conductor runs at least to the opposite end of the outer conductor. Electrical signals are connected to a driven end of both the outer and inner conductors, where these signals supply power to/from the antenna whenever it is used as a transmitter/receiver, and neither of these signals needs to be connected to an electrical ground.

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.

An antenna structure includes a patch antenna including two opposite edges, a microstrip line connected to the patch antenna, two first radiation assemblies respectively disposed on two sides of the patch antenna, two second radiation assemblies disposed under the two first radiation assemblies, a liquid crystal layer disposed between a first plane and a second plane, and a ground plane disposed under the two second radiation assemblies. The patch antenna, the microstrip line, and the two first radiation assemblies are located on the first plane, and each of the first radiation assemblies includes multiple separated first conductors. The two second radiation assemblies are located on the second plane, and each of the second radiation assemblies includes multiple separated second conductors. A projection of the two second radiation assemblies on the first plane, the two first radiation assemblies, and the two edges of the patch antenna collectively form two loops.

A method of providing a single structure multiple mode antenna is described. The antenna is preferably constructed having a first inductor coil that is electrically connected in series with a second inductor coil. The antenna is constructed having a plurality of electrical connections positioned along the first and second inductor coils. A plurality of terminals is connected to the electrical connections that facilitate numerous electrical connections and enables the antenna to be selectively tuned to various frequencies and frequency bands.

An antenna for receiving wireless power from a transmitter is provided. The antenna includes multiple antenna elements, coupled to an electronic device, configured to receive radio-frequency (RF) power waves from the transmitter, each antenna element being adjacent to at least one other antenna element. Furthermore, the multiple antenna elements are arranged so that an efficiency of reception of the RF power waves by the antenna elements remains above a predetermined threshold efficiency when a human hand is in contact with the electronic device, the predetermined threshold efficiency being at least 50%. Lastly, at least one antenna element is coupled to conversion circuitry, which is configured to (i) convert energy from the received RF power waves into usable power and (ii) provide the usable power to the electronic device for powering or charging of the electronic device.

A method of providing a single structure multiple mode antenna is described. The antenna is preferably constructed having a first inductor coil that is electrically connected in series with a second inductor coil. The antenna is constructed having a plurality of electrical connections positioned along the first and second inductor coils. A plurality of terminals is connected to the electrical connections that facilitate numerous electrical connections and enables the antenna to be selectively tuned to various frequencies and frequency bands.

A printed antenna may include a loop antenna body, a feed port, and a switch component. The loop antenna body includes a first end and a second end, there is a spacing between the first end and the second end, a connection line between the first end and the second end forms a closed loop with the loop antenna body. The feed module is configured to output a feed signal to the loop antenna body by using the feed port. The loop antenna body includes a plurality of loop antenna branches, the switch component is disposed between every two adjacent loop antenna branches, and the switch component is configured to connect or disconnect the two adjacent loop antenna branches.

A controllable electrical outlet may comprise a resonant loop antenna. The resonant loop antenna may comprise a feed loop electrically coupled to a radio-frequency (RF) communication circuit and a main loop magnetically coupled to the feed loop. The controllable electrical outlet may comprise one or more electrical receptacles configured to receive a plug of a plug-in electrical load and may be configured to control power delivered to the plug-in electrical load in response to an RF signal received via the RF communication circuit. The RF performance of the controllable electrical outlet may be substantially immune to devices plugged into the receptacles (e.g., plugs, power supplies, etc.) due to the operation of the resonant loop antenna. For example, degradation of the RF performance of the controllable electrical outlet may be less when the controllable electrical outlet includes the resonant loop antenna rather than other types of antennas.

Systems and methods for operating a radio system include configuring a first antenna of a plurality of antennas in a wireless device to operate in a configured mode of a plurality of modes, wherein the plurality of modes include a first mode of operating as a quarter wave for operation in a 2.4 GHz band, a second mode of operating as a half wave for operation in a 5 GHz band, and a third mode of operating simultaneous as a half wave and a quarter wave for operation in both the 2.4 GHz band and the 5 GHz band; and operating a first radio of a plurality of radios connected to the first antenna in the configured mode of the first antenna.

An independent tuning system for an antenna, a tuning method, and a communication device are disclosed. The independent tuning system for the antenna is applicable to a communication device. The communication device includes an antenna tuner, a tuning driver and a tuning program. The tuning program includes: a storage component, an input component, a matching component, and a tuning component. A tuning parameter corresponding to optimized antenna efficiency is matched according to a tuning parameter input by a user and a graph or curve chart of correspondence information between tuning parameters and antenna efficiency stored in the tuning component. An NV value of the tuning driver is tuned according to the tuning parameter to achieve independent optimized tuning of the antenna.