Abstract: A signal processing circuit is disclosed, comprising a first node for coupling with a first antenna, a second node for coupling with a second antenna, a third node for receiving a first signal from a transmitting circuit, a fourth node for coupling with a receiving circuit, a signal dividing circuit, a phase shifting circuit, and a signal combining circuit. The signal dividing circuit divides the first signal into a second signal and a third signal, and transmits the second signal to the first antenna. The phase shifting circuit shifts the phase of the third signal to generate a fourth signal for canceling at least part of a coupled signal between the third node and the fourth node. The signal combining circuit combines the fourth signal and a fifth signal received from the second antenna, and transmits the combined signal to the receiving circuit.

Abstract: A dual-band antenna is disclosed, comprising a radiating body, a shorting element, and a feeding element. The radiating body comprises a plurality of radiating portions located in a first, a second, a third, and a fourth planes, respectively. The shorting element and the feeding element both extend from the radiating body and are located in the first plane. The radiating portions located in the first, the second, and the third planes transmit and/or receive signals in a first frequency band. The radiating portions located in the first, the second, and the fourth planes transmit and/or receive signals in a second frequency band. A first angle between the first and the second planes, a second angle between the second and the third planes, and a third angle between the second and the fourth planes range between 80 degrees to 100 degrees.

Abstract: The present invention discloses a planar antenna including a substrate, a ground plane and a feed line. The ground plane is disposed on one side of the substrate. The ground plane includes a hollow portion. The feed line disposed on another side of the substrate and corresponding to the hollow portion for feeding a signal. The present invention also discloses a planar antenna including a substrate, a ground plane and a feed line. The ground plane is disposed on one side of the substrate. The ground plane includes a first hollow portion and a second hollow portion. The feed line is disposed on another side of the substrate and having a first branch feed portion and a second branch feed portion for feeding a signal, and the first branch feed portion and the second branch feed portion are aligned with the first hollow portion and the second hollow portion respectively.

Abstract: An inverted-F antenna is disclosed including: a radiating body including a plurality of radiating portions, and some of the radiating portions located on a same plane; a shorting element extending outward from the radiating body and forming a first predetermined included angle with one of the radiating portions; a feeding element extending outward from the radiating body and forming a second predetermined included angle with one of the radiating portions; and a protrusion extending outward from the radiating body and forming a third predetermined included angle with one of the radiating portions; wherein at least one of the first, second, and third predetermined included angles is substantially a right angle.

Abstract: A dipole antenna used in an operation frequency includes a dipole radiation main body, a first semi-loop metal line and a second semi-loop metal line is provided. The dipole radiation main body has a first radiation line arm and a second radiation line arm aligned in a straight line, wherein a gap exists therebetween to form a feeding terminal. The first semi-loop metal line has two ends respectively connected to the first radiation line arm and the second radiation line arm to form a first matching loop covering the feeding terminal. The second semi-loop metal line has two ends respectively connected to the first radiation line arm and the second radiation line arm to form a second matching loop, which is larger than the first matching loop.

Abstract: An electromagnetic band-gap structure includes a circuit board, a ground plane and a plurality of electromagnetic band-gap units. The circuit board includes a first side and a second surface, and the ground plane disposed on the first side. The plurality of electromagnetic band-gap units are located on both the first surface and the second surface and connected to each other along an edge of the ground plane. Every electromagnetic band-gap unit includes a first strip line, a second strip line and a via. The first strip line is located on the first side, including a first relative long strip line and a first relative short strip line connected to the ground. The second strip line is located on the second side. The second strip line is connected to the first strip line of the adjacent electromagnetic band-gap unit through the via.

Abstract: Disclosed is a planar inverted-F antenna with an extended grounding plane. The planar inverted-F antenna has a grounding metal plate having a selected side edge on which the extended grounding plane is formed and has a predetermined height. At least one antenna signal radiating plate is connected to the grounding metal plate by a short-circuit piece and is substantially parallel to and spaced from the grounding metal plate by a distance. A feeding point extends from the antenna signal radiating plate in a direction toward the grounding metal plate and corresponds to the extended grounding plane with a predetermined gap therebetween. With the arrangement of the extended grounding plane, the impedance matching of the antenna is improved and the impedance bandwidth of the antenna is increased.

Abstract: The present invention discloses a planar antenna including a substrate, a ground plane and a feed line. The ground plane is disposed on one side of the substrate. The ground plane includes a hollow portion. The feed line disposed on another side of the substrate and corresponding to the hollow portion for feeding a signal. The present invention also discloses a planar antenna including a substrate, a ground plane and a feed line. The ground plane is disposed on one side of the substrate. The ground plane includes a first hollow portion and a second hollow portion. The feed line is disposed on another side of the substrate and having a first branch feed portion and a second branch feed portion for feeding a signal, and the first branch feed portion and the second branch feed portion are aligned with the first hollow portion and the second hollow portion respectively.

Abstract: A dipole antenna used in an operation frequency includes a dipole radiation main body, a first semi-loop metal line and a second semi-loop metal line is provided. The dipole radiation main body has a first radiation line arm and a second radiation line arm aligned in a straight line, wherein a gap exists therebetween to form a feeding terminal. The first semi-loop metal line has two ends respectively connected to the first radiation line arm and the second radiation line arm to form a first matching loop covering the feeding terminal. The second semi-loop metal line has two ends respectively connected to the first radiation line arm and the second radiation line arm to form a second matching loop, which is larger than the first matching loop.

Abstract: Disclosed is a planar inverted-F antenna with an extended grounding plane. The planar inverted-F antenna has a grounding metal plate having a selected side edge on which the extended grounding plane is formed and has a predetermined height. At least one antenna signal radiating plate is connected to the grounding metal plate by a short-circuit piece and is substantially parallel to and spaced from the grounding metal plate by a distance. A feeding point extends from the antenna signal radiating plate in a direction toward the grounding metal plate and corresponds to the extended grounding plane with a predetermined gap therebetween. With the arrangement of the extended grounding plane, the impedance matching of the antenna is improved and the impedance bandwidth of the antenna is increased.

Abstract: An ultra wideband antenna includes a substrate, a transmission line coupled to the substrate, and a radiating element coupled to the transmission line at a distance from the substrate and being symmetric about the transmission line. An outer edge of the radiating element has a shape defined by a binomial function.