A unit cell can be used for a metasurface, metamaterial, or beamforming antenna. The unit cell includes a metal layer attached to a substrate. The metal layer defines an iris opening for the unit cell. One or more tunable capacitance devices are positioned within or across the iris opening. Each tunable capacitance device is to tune resonance frequency of the unit cell. Mass transfer technologies or self-assembly processes may be used to position the tunable capacitance devices.

An electronic device is provided. The electronic device includes a foldable housing, a flexible display, at least one printed circuit board (PCB), and a wireless communication circuit. The foldable housing includes a hinge structure, a first housing structure connected to the hinge structure and including a first surface facing in a first direction, a second surface facing in a direction opposite to the first direction, and a first lateral member surrounding a first space between the first surface and the second surface, and a second housing structure connected to the hinge structure and including a third surface facing in a second direction, a fourth surface facing in a direction opposite to the second direction, and a second lateral member surrounding a second space between the third surface and the fourth surface.

Adaptive self-tunable antenna systems and methods are provided including a closed-loop system for sensing near-field RF signals of transmitted RF signals and tuning an antenna or switching between multiple antennas, so that the strength of the transmitted RF signals is maximized. A sensing antenna detects the near-field RF signal, which is filtered and converted to an RF strength control signal that can be used to generate an antenna tuning control signal. An antenna tuner uses the antenna tuning control signal to keep the antenna in resonance by dynamically changing the electrical length of the antenna or switching between multiple antennas to maximize the strength of the radiated RF signal. Such antennas may be less prone to detuning due to interaction with human bodies or other objects. Dynamically matching the antennas to an RF power amplifier and low noise amplifier can improve stability, power efficiency, gain, noise figure, and receiver sensitivity.

Example electronic devices with adjustable antennas as disclosed. In an example, the electronic device includes a housing, and an antenna disposed within the housing. The antenna includes a slot extending between a first conductive surface and a second conductive surface, and a contact clip coupled to the first conductive surface and the second conductive surface so that the first conductive surface is coupled to the second conductive surface through the contact clip. The contact clip is to move along the slot to adjust an operating frequency of the antenna.

Example electronic devices with adjustable antennas as disclosed. In an example, the electronic device includes a housing, and an antenna disposed within the housing. The antenna includes a slot extending between a first conductive surface and a second conductive surface, and a contact clip coupled to the first conductive surface and the second conductive surface so that the first conductive surface is coupled to the second conductive surface through the contact clip. The contact clip is to move along the slot to adjust an operating frequency of the antenna.

Methods, apparatus and systems are provided including a load-adaptive antenna for mobile communication devices. One aspect provides a method of using an antenna within a handheld wireless communication device. The method includes monitoring antenna performance using information received from a sensor within the device. When antenna performance drops below a programmable threshold, such as due to proximity or contact with a user, a signal from a processor is used to actuate a circuit component to change a location of a high impedance portion of the antenna to reduce the effects of the proximity or contact with the user, in various embodiments.

A method of tuning an electrically small antenna comprising a radiating element and a support structure comprises applying a force to the support structure to change a shape or a dimension of the radiating element to increase or decrease a frequency at which the electrically small antenna resonates.

A method of tuning an electrically small antenna comprising a radiating element and a support structure comprises applying a force to the support structure to change a shape or a dimension of the radiating element to increase or decrease a frequency at which the electrically small antenna resonates.

The present subject matter relates to filtering antenna devices, systems, and methods in which a tunable antenna having one or more first variable impedance element is configured to selectively vary an impedance at a signal path output and a tunable filter is in communication between the signal path output of the tunable antenna and a signal processing chain. The tunable filter can have one or more second variable impedance element configured to provide a frequency-selective filtering response between the signal path output and the signal processing chain. A controller in communication with both the tunable antenna and the tunable filter can be configured for selectively tuning an impedance value of one or more of the one or more first variable impedance element or the one or more second variable impedance element.

A multi-frequency antenna comprising an IMD element, one or more active tuning elements and one or more parasitic elements. The IMD element is used in combination with the active tuning and parasitic elements for enabling a variable frequency at which the antenna operates, wherein, when excited, the parasitic elements may couple with the IMD element to change an operating characteristic of the IMD element.