An antenna device configured to be attached to a vehicle includes: an antenna of a resonance type; and a matching circuit connected to the antenna, wherein the matching circuit includes a first matching circuit connected to a feeding portion of the antenna and a second matching circuit connected to a subsequent stage of the first matching circuit, wherein the first matching circuit reduces an impedance in a frequency band that is away to a higher-frequency range or a lower-frequency range from a resonance point of the antenna such that the impedance is lower than before connection of the first matching circuit, and the second matching circuit increases an impedance in a vicinity of the resonance point of the antenna such that the impedance is higher than before connection of the second matching circuit.

An antenna device configured to be attached to a vehicle includes: an antenna of a resonance type; and a matching circuit connected to the antenna, wherein the matching circuit includes a first matching circuit connected to a feeding portion of the antenna and a second matching circuit connected to a subsequent stage of the first matching circuit, wherein the first matching circuit reduces an impedance in a frequency band that is away to a higher-frequency range or a lower-frequency range from a resonance point of the antenna such that the impedance is lower than before connection of the first matching circuit, and the second matching circuit increases an impedance in a vicinity of the resonance point of the antenna such that the impedance is higher than before connection of the second matching circuit.

An antenna structure with wide bandwidth in a reduced physical space includes a housing, a side wall, and a first feed portion. The housing includes a metal side frame, a metal middle frame, and a metal back board. The side wall is made of metal material. The metal middle frame and the metal back board are coupled to two sides of the side wall, and the metal middle frame is parallel to the metal back board. The metal side frame surrounds the metal back board. The metal side frame defines at least one gap. The metal back board defines a slot. The slot and the at least one gap cooperatively divide at least two radiation portions from the metal side frame. A wireless communication device employing the antenna structure is also provided.

An antenna structure with wide bandwidth in a reduced physical space includes a housing, a side wall, and a first feed portion. The housing includes a metal side frame, a metal middle frame, and a metal back board. The side wall is made of metal material. The metal middle frame and the metal back board are coupled to two sides of the side wall, and the metal middle frame is parallel to the metal back board. The metal side frame surrounds the metal back board. The metal side frame defines at least one gap. The metal back board defines a slot. The slot and the at least one gap cooperatively divide at least two radiation portions from the metal side frame. A wireless communication device employing the antenna structure is also provided.

An apparatus and associated method are provided involving a housing having a periphery configured to operate as a second antenna, a third antenna, and a fourth antenna. The periphery includes a top wall having a first slot formed therein, a first side wall having a second slot formed therein, and a second side wall having a third slot formed therein. The top wall is arranged between the first side wall and the second side wall, and a top portion of the periphery is defined between the second slot and the third slot. The top portion is divided into a first top side portion and a second top side portion via the first slot. Further, the first top side portion operates as the second antenna, and the second top side portion operates as both the third antenna and the fourth antenna.

A mobile terminal including a first frame, and a second frame capable of switching a state thereof to an extended state by moving in a first direction from the first frame, and to a contracted state by sliding in a second direction opposite to the first direction, wherein the second frame includes a rear portion for at least partially covering a rear surface of the first frame, wherein the first frame includes a first rear surface exposed rearwardly in the contracted state, a second rear surface located frontwardly of the rear portion and not exposed to the outside in the contracted state, wherein at least a portion of the second rear surface is exposed rearwardly in the extended state, and a third rear surface covered by the rear portion in the contracted state and in the extended state.

A mobile terminal including a first frame, and a second frame capable of switching a state thereof to an extended state by moving in a first direction from the first frame, and to a contracted state by sliding in a second direction opposite to the first direction, wherein the second frame includes a rear portion for at least partially covering a rear surface of the first frame, wherein the first frame includes a first rear surface exposed rearwardly in the contracted state, a second rear surface located frontwardly of the rear portion and not exposed to the outside in the contracted state, wherein at least a portion of the second rear surface is exposed rearwardly in the extended state, and a third rear surface covered by the rear portion in the contracted state and in the extended state.

A wireless device includes at least one slim radiating system having a slim radiating structure and a radio-frequency system. The slim radiating structure includes one or more booster bars. The booster bar has slim width and height factors that facilitate its integration within the wireless device and the excitation of a resonant mode in the ground plane layer, and has a location factor that enables it to achieve the most favorable radio-frequency performance for the available space to allocate the booster bar. The at least one slim radiating system may be configured to transmit and receive electromagnetic wave signals in one or more frequency regions of the electromagnetic spectrum.

A wireless device includes at least one slim radiating system having a slim radiating structure and a radio-frequency system. The slim radiating structure includes one or more booster bars. The booster bar has slim width and height factors that facilitate its integration within the wireless device and the excitation of a resonant mode in the ground plane layer, and has a location factor that enables it to achieve the most favorable radio-frequency performance for the available space to allocate the booster bar. The at least one slim radiating system may be configured to transmit and receive electromagnetic wave signals in one or more frequency regions of the electromagnetic spectrum.

An antenna structure includes a ground, a first patch, a second patch, a first conductive post, and a second conductive post. The first patch is spaced apart from the ground. The first patch includes a circular slit, a main patch portion and a circular portion. The circular portion and the circular slit surround the main patch portion, and the circular slit is located between the main patch portion and the circular portion. The second patch is disposed between and spaced apart from the ground and the main patch portion. A dimension of the second patch is less than a dimension of the main patch portion. One end of the first conductive post is connected to the second patch. Another end of the first conductive post passes through the ground and is coupled to a signal feeding end. The circular portion is connected to the ground through the second conductive post.