An antenna structure includes a substrate, a first radiating element, a second radiating element, a signal transmission assembly, a grounding member, and a feed-in element. The first radiating element is disposed on the substrate. The second radiating element is disposed on the substrate. The signal transmission assembly is disposed on the substrate. The signal transmission assembly includes a signal transmission line, a first impedance matching circuit, and a filter. The signal transmission assembly is coupled between the first radiating element and the second radiating element. The first impedance matching circuit is coupling to the first radiating element and the signal transmission line. The filter is coupling to the second radiating element and the signal transmission line. The feed-in element is coupled between the signal transmission line and the grounding member.

A vehicle-body-embedded antenna device includes an antenna element, a circuit board, a coil and a ground bracket. The antenna element of a grounded type has an antenna capacitance adapted to function as a capacitive antenna that supports a first frequency band, and main polarization thereof is polarization substantially parallel to the roof surface. The coil is placed on the circuit board and connected to the power feeding part to which the antenna element is connected for making the antenna element to have an antenna length supporting a second frequency band. The ground bracket is directly grounded to a conductive member of the vehicle body which is provided at an angle different from an angle of the roof surface for improving polarization sensitivity of the antenna element substantially perpendicular to the roof surface.

A vehicle-body-embedded antenna device includes an antenna element, a circuit board, a coil and a ground bracket. The antenna element of a grounded type has an antenna capacitance adapted to function as a capacitive antenna that supports a first frequency band, and main polarization thereof is polarization substantially parallel to the roof surface. The coil is placed on the circuit board and connected to the power feeding part to which the antenna element is connected for making the antenna element to have an antenna length supporting a second frequency band. The ground bracket is directly grounded to a conductive member of the vehicle body which is provided at an angle different from an angle of the roof surface for improving polarization sensitivity of the antenna element substantially perpendicular to the roof surface.

The present invention provides an antenna module and a mobile terminal. The mobile terminal comprises a back cover, a main board, a plastic back shell, and a USB interface, the antenna module comprises a radiator structured on a surface of the plastic back shell facing the back cover and a feeding point and a grounding point disposed on the main board, the antenna module further comprises a matching network, a first tuning switch, a second tuning switch and a third tuning switch, the surface of the plastic back shell facing the back cover includes a first structuring region for structuring the radiator and a second region other than the first structuring region, the radiator completely covers the first structuring region, and the orthographic projections of the radiator and the USB interface on the main board do not overlap each other.

A dual band compatible antenna device includes a first branch electrode having a first electrode portion connected to a common electrode with a first adjustment element interposed between the first electrode portion and the common electrode and a second branch electrode having a second electrode portion connected to the common electrode with a second adjustment element interposed between the second electrode portion and the common electrode. The first electrode portion and the second electrode portion are provided on a line to have a length equal to or longer than of an electrical length of the first branch electrode and the second branch electrode.

Patch antennas include four radiation elements arrayed in a rectangular lattice pattern at four positions around a feeding point in the electrode, and wiring which electrically couples each of the radiation elements and the feeding point with an equal wiring length, and is fed by a line-shaped feeding conductor arranged at a position intersecting slots formed at a ground conductor plate, where the feeding conductor has a repetitive branch pattern in which multiple pieces of line-shaped wiring are connected in T-shapes being perpendicular to each other at a total of 2.sup.N1 branch points from a base end to each of the tips, and each of the tips is bent in a same direction in the second direction from a terminal end of the line-shaped wiring to which the tip is connected.

Patch antennas include four radiation elements arrayed in a rectangular lattice pattern at four positions around a feeding point in the electrode, and wiring which electrically couples each of the radiation elements and the feeding point with an equal wiring length, and is fed by a line-shaped feeding conductor arranged at a position intersecting slots formed at a ground conductor plate, where the feeding conductor has a repetitive branch pattern in which multiple pieces of line-shaped wiring are connected in T-shapes being perpendicular to each other at a total of 2.sup.N1 branch points from a base end to each of the tips, and each of the tips is bent in a same direction in the second direction from a terminal end of the line-shaped wiring to which the tip is connected.

An apparatus includes an impedance matching circuit for matching an impedance of a high quality factor (high-Q) antenna to an impedance of a radio-frequency (RF) circuit. The impedance matching network includes a first reactive network. The impedance matching network also includes a second reactive network coupled in series with the first reactive network. The second reactive network includes a reactive component realized by multiple reactive components so as to reduce sensitivity of the impedance matching network to component tolerances in the second reactive network.

An apparatus includes an impedance matching circuit for matching an impedance of a high quality factor (high-Q) antenna to an impedance of a radio-frequency (RF) circuit. The impedance matching network includes a first reactive network. The impedance matching network also includes a second reactive network coupled in series with the first reactive network. The second reactive network includes a reactive component realized by multiple reactive components so as to reduce sensitivity of the impedance matching network to component tolerances in the second reactive network.

An antenna system and a mobile terminal are provided. The antenna system includes a front frame rib connecting a system ground with a first short-axis frame, a slit provided on a first long-axis frame, a radio frequency front end area provided in system ground, and first and second frame-joint points each connecting radio frequency front end area with a metal frame. The first and second frame-joint points are located between front frame rib and slit. The radio frequency front end area includes a feeding point, a matching circuit, an impedance tuning circuit and a switching circuit. The impedance tuning circuit and the switching circuit are adjusted to switch an operating state of antenna system in such a manner that the antenna system operates in different frequency bands. The antenna system includes one operating state in which the antenna system operates in a frequency band ranging from 1710 MHz to 2700 MHz.