An antenna structure includes a housing and a first feed source. The first feed source is electrically coupled to a first radiating portion of the housing and adapted to provide an electric current to the first radiating portion.

An antenna structure includes a housing and a first feed source. The first feed source is electrically coupled to a first radiating portion of the housing and adapted to provide an electric current to the first radiating portion.

An antenna structure includes a housing, a first feed source, a second feed source, a third feed source, and a radiating body. The first feed source is electrically coupled to a first radiating portion of the housing and adapted to provide an electric current to the first radiating portion. The second feed source is electrically coupled to the second radiating portion and adapted to provide an electric current to the second radiating portion. The radiating body is mounted within the housing and electrically coupled to the third feed source. The third feed source provides an electric current to the radiating body.

An antenna structure includes a housing, a first feed source, a second feed source, a third feed source, and a radiating body. The first feed source is electrically coupled to a first radiating portion of the housing and adapted to provide an electric current to the first radiating portion. The second feed source is electrically coupled to the second radiating portion and adapted to provide an electric current to the second radiating portion. The radiating body is mounted within the housing and electrically coupled to the third feed source. The third feed source provides an electric current to the radiating body.

An antenna structure includes a housing, a first feed source, and a second feed source. The first feed source is electrically coupled to a first radiating portion of the housing and adapted to provide an electric current to the first radiating portion. The second feed source is electrically coupled to one of a second radiating portion or a third radiating portion of the housing. The other one of the second radiating portion or the third radiating portion is electrically coupled to the first radiating portion.

An antenna structure includes a housing, a first feed source, and a second feed source. The first feed source is electrically coupled to a first radiating portion of the housing and adapted to provide an electric current to the first radiating portion. The second feed source is electrically coupled to one of a second radiating portion or a third radiating portion of the housing. The other one of the second radiating portion or the third radiating portion is electrically coupled to the first radiating portion.

An antenna structure includes a housing, a first feed source, and a second feed source. The first feed source is electrically coupled to a first radiating portion of the housing and adapted to provide an electric current to the first radiating portion. The second feed source is electrically coupled to one of a second radiating portion or a third radiating portion of the housing. The other one of the second radiating portion or the third radiating portion is electrically coupled to the first radiating portion.

A wireless communication device includes a first antenna, a second antenna, a first switching circuit, and a first tunable matching circuit. The first switching circuit is electrically connected to the first antenna, the second antenna, and the first tunable matching circuit. In a first operation mode, the first antenna of the wireless communication device performs signal transmission or reception, an impedance value corresponding to the first tunable matching circuit is adjusted to a first impedance value, and the second antenna is conducted to the first tunable matching circuit through the first switching circuit. In a second operation mode, the second antenna of the wireless communication device performs signal transmission or reception, the impedance value corresponding to the first tunable matching circuit is adjusted to a second impedance value, and the first antenna is conducted to the first tunable matching circuit through the first switching circuit.

A wireless communication device includes a first antenna, a second antenna, a first switching circuit, and a first tunable matching circuit. The first switching circuit is electrically connected to the first antenna, the second antenna, and the first tunable matching circuit. In a first operation mode, the first antenna of the wireless communication device performs signal transmission or reception, an impedance value corresponding to the first tunable matching circuit is adjusted to a first impedance value, and the second antenna is conducted to the first tunable matching circuit through the first switching circuit. In a second operation mode, the second antenna of the wireless communication device performs signal transmission or reception, the impedance value corresponding to the first tunable matching circuit is adjusted to a second impedance value, and the first antenna is conducted to the first tunable matching circuit through the first switching circuit.

A substrate integrated waveguide (SIW) slot antenna may include a substrate that may have a first substrate portion with a first permittivity less than and a second substrate portion with a second permittivity. The substrate may include a top surface and a bottom surface. The exemplary SIW slot antenna may further include a first conductive layer disposed on the top surface, a second conductive layer disposed on the bottom surface, a transverse slot on the first conducting layer, waveguide sidewalls that may include a plurality of spaced-apart metal-lined vias traversing the substrate, and a microstrip feed line on the first conducting layer.