A multi-band antenna including a ground portion, a first radiation portion, a second radiation portion, a feeding portion and a matching portion is provided. The first radiation portion is disposed beside the ground portion, a first gap is existed between the ground portion and the first radiation portion so as to form a first slot, and the first slot has a first open terminal located at the first gap. The second radiation portion is connected to the first radiation portion. The feeding portion is located between the first radiation portion and the second radiation portion. The matching portion is located in the first slot and connected to the first radiation portion and the ground portion. The feeding portion excites the first slot to generate a first resonant mode. The second radiation portion generates a second resonant mode.

A multi-band antenna including a ground portion, a first radiation portion, a second radiation portion, a feeding portion and a matching portion is provided. The first radiation portion is disposed beside the ground portion, a first gap is existed between the ground portion and the first radiation portion so as to form a first slot, and the first slot has a first open terminal located at the first gap. The second radiation portion is connected to the first radiation portion. The feeding portion is located between the first radiation portion and the second radiation portion. The matching portion is located in the first slot and connected to the first radiation portion and the ground portion. The feeding portion excites the first slot to generate a first resonant mode. The second radiation portion generates a second resonant mode.

An antenna includes: a first substrate and a second substrate; a first antenna electrode is disposed on a side of the first substrate away from the second substrate; a second antenna electrode is disposed on a side of the second substrate away from the first substrate and a microstrip line is disposed on a side of the second substrate close to the first substrate; a liquid crystal layer is disposed between the first substrate and the second substrate; at least one drive electrode assembly is disposed between the first substrate and the second substrate. The at least one drive electrode assembly is configured to achieve impedance matching of the antenna by controlling liquid crystal molecules of the liquid crystal layer to deflect.

Embodiments of a circuit, system, and method are disclosed. In an embodiment, a circuit includes a first microstrip transmission line, a second microstrip transmission line, and a slotline formation, wherein the slotline formation extends between the first microstrip transmission line and the second microstrip transmission line so that the slotline formation is configured to electromagnetically couple the first microstrip transmission line to the second microstrip transmission line during operation of the circuit. In addition, the circuit includes at least one controllable capacitance circuit electrically connected to at least one of the first microstrip transmission line and the second microstrip transmission line, wherein a magnitude of capacitance of the at least one controllable capacitance circuit is controllable (e.g., in response to a capacitance control signal received at a control interface).

Embodiments of a circuit, system, and method are disclosed. In an embodiment, a circuit includes a first microstrip transmission line, a second microstrip transmission line, and a slotline formation, wherein the slotline formation extends between the first microstrip transmission line and the second microstrip transmission line so that the slotline formation is configured to electromagnetically couple the first microstrip transmission line to the second microstrip transmission line during operation of the circuit. In addition, the circuit includes at least one controllable capacitance circuit electrically connected to at least one of the first microstrip transmission line and the second microstrip transmission line, wherein a magnitude of capacitance of the at least one controllable capacitance circuit is controllable (e.g., in response to a capacitance control signal received at a control interface).

An antenna system and a mobile terminal are provided. The antenna system includes a metal frame, a mainboard received inside the metal frame, and a first feeding point, a second feeding point, a first grounding point and a second grounding point provided on the mainboard. The metal frame includes a bottom frame separated by the breach into a first radiation portion located at the bottom left corner and a second radiation portion located at the bottom right corner. A first antenna is formed by feeding of the first feeding point, a second antenna is formed by feeding of the second feeding point, a working frequency of the first antenna covers LTE low frequency, and the working frequencies of the first antenna and the second antenna cover LTE intermediate frequency and high frequency & 3.4-3.8 GHz & C frequency band.

An antenna module and a mobile device are provided. The antenna module includes a radiator formed on a surface of the plastic rear housing facing the back cover, and a feed point, a first ground point, and a second ground point that are disposed on the motherboard. The antenna module further includes a matching network, a first tuning switch, and a second tuning switch. The feed point is connected to the radiator through the matching network. The first ground point is connected to the radiator through the first tuning switch. The second ground point is connected to the radiator through the second tuning switch. The surface of the plastic rear housing facing the back cover includes a first shaping zone for shaping the radiator and a second zone other than the first shaping zone, and the radiator completely covers the first shaping zone.

The present invention provides an antenna system applied to a mobile terminal. The mobile terminal includes a metal bezel, a plastic back shell and a main board. The antenna system includes a metal trace. The metal trace includes a feed section, a radiating section, a first loop unit and a second loop unit. The main board is provided with one feed point connected to both the feed section and the metal bezel, two ground points respectively connected to an end, away from the feed section, of the first loop unit and an end, away from the feed section, of the second loop unit, and a tuning switch connected to the metal bezel.

An electronic device is provided. The electronic device includes a housing including a first plate, a second plate facing the first plate, and a side member surrounding a space between the first plate and the second plate and a circuit board, which is accommodated inside a housing and in which a wireless communication circuit is disposed. The second plate includes a slot filled with a non-conductive material. An area other than the slot is formed of a conductive material. The circuit board includes a conductive pattern formed on the circuit board along with the slot of the second plate, and the wireless communication circuit is configured to feed one point of the second plate adjacent to the slot to receive a signal of a first frequency band through an electrical path formed by the slot and to feed the conductive pattern to receive a signal of a second frequency band through the slot.

An electronic device is provided. The electronic device includes a housing including a first plate, a second plate facing the first plate, and a side member surrounding a space between the first plate and the second plate and a circuit board, which is accommodated inside a housing and in which a wireless communication circuit is disposed. The second plate includes a slot filled with a non-conductive material. An area other than the slot is formed of a conductive material. The circuit board includes a conductive pattern formed on the circuit board along with the slot of the second plate, and the wireless communication circuit is configured to feed one point of the second plate adjacent to the slot to receive a signal of a first frequency band through an electrical path formed by the slot and to feed the conductive pattern to receive a signal of a second frequency band through the slot.