Abstract: An antenna array is provided, which may include a connection portion and a plurality of antenna units. The antenna units may be disposed on the two sides of the connection portion respectively. The proximal end of each of the antenna units may be connected to the connection portion and the distal end of one or more of the antenna units may be grounded. The length of each of the antenna units may be less than or equal to ¼ wavelength of the operating frequency of the antenna array, and the distance between any two adjacent antenna units may be less than or equal to ½ wavelength of the operating frequency of the antenna array.

Abstract: An antenna array is provided, which may include a connection portion and a plurality of antenna units. The antenna units may be disposed on the two sides of the connection portion respectively. The proximal end of each of the antenna units may be connected to the connection portion and the distal end of one or more of the antenna units may be grounded. The length of each of the antenna units may be less than or equal to ¼ wavelength of the operating frequency of the antenna array, and the distance between any two adjacent antenna units may be less than or equal to ½ wavelength of the operating frequency of the antenna array.

Abstract: An antenna module is provided, which includes a first antenna set and a second antenna set. The first antenna set includes a first transmitter end and a first receiver end, and provides a detection range, less than or substantially equal to 180°, in the direction of a first plane. The second antenna set includes a second transmitter end and a second receiver end, and provides a detection range, substantially equal to 180°, in the direction of a second plane. The polarization direction of the first antenna set is perpendicular to the polarization direction of the second antenna set; the first plane, the second plane and the plane where the antenna module is disposed are perpendicular to one another.

Abstract: A radar antenna system comprises a plurality of transmitting sub-arrays; a plurality of receiving sub-arrays; and a transceiving control unit coupled to the plurality of transmitting sub-arrays and the plurality of receiving sub-arrays, configured to control the plurality of transmitting sub-arrays and the plurality of receiving sub-arrays, such that the radar antenna system selectively operates in one of an amplitude-comparison mono-pulse mode and a phase-comparison mono-pulse mode.

Abstract: A vehicular radar system includes a plurality of transmitting sub-arrays and a transmission power divider. The plurality of transmitting sub-arrays are symmetric with respect to a symmetry axis, and the plurality of transmitting sub-arrays are parallel to the symmetry axis. The transmission power divider, coupled to the plurality of transmitting sub-arrays, is configured to apply a plurality of phases and a plurality of amplitudes to the plurality of transmitting sub-arrays. A first transmitting sub-array, among the plurality of transmitting sub-arrays and closest to the symmetry axis, and a second transmitting sub-array, among the plurality of transmitting sub-arrays and farthest away from the symmetry axis, have a phase difference in between, and the phase difference is between 120 degrees and 180 degrees.

Abstract: A radar and a method for enabling array antenna are proposed. The radar includes a transceiver, a multi-input multi-output (MIMO) array antenna, a phased array antenna, and a controller. The MIMO array antenna is coupled to the transceiver and includes first transmitting sub-arrays and receiving sub-arrays. The phased array antenna is coupled to the transceiver and includes second transmitting sub-arrays and the receiving sub-arrays. The controller is coupled to the transceiver and configured to to enable the first transmitting sub-arrays to form the MIMO array antenna or enable the second transmitting sub-arrays to form the phased array antenna.

Abstract: An array antenna forms a main beam, and the main beam is toward a beam direction. The array antenna includes a plurality of radiating elements with a plurality of central line segments, where the plurality of radiating elements are arranged along a straight line, and the straight line is connecting the plurality of central line segments; and a plurality of meanders connecting the plurality of radiating elements; where the array antenna is disposed on a first plane, the beam direction has a nonzero deviating angle with a normal direction of the first plane, and the normal direction is perpendicular to the first plane.

Abstract: A radio-frequency (RF) system includes a substrate; a plurality of antenna strings, formed on a first plane of the substrate, each comprising a plurality of radiating units connected in a sequence, wherein the plurality of antenna strings are classified into a first group and a second group; a plurality of wires, formed on a second plane of the substrate, for transmitting RF signals; a plurality of connecting units, disposed in the substrate, for coupling the plurality of wires and antenna strings of the second group; a first RF processing module, for transmitting or receiving RF signals via antenna strings of the first group, and a second RF processing module, for coupling to the antenna strings of the second group through the plurality of wires and the plurality of connecting units, so as to transmit or receive RF signals via the antenna strings of the second group.

Abstract: A balun filter utilized for a radio-frequency (RF) system includes a first terminal coupled to an antenna of the RF system for delivering an RF signal; a differential port has a second terminal and a third terminal for delivering a differential signal; a band pass filter coupled between the first terminal and the differential port has a plurality of resonators, each including a surrounding line substantially surrounding an area and forming a loophole on a side of the each resonator; and at least a line segment connected to the surrounding line and disposed separately within the area surrounded by the surrounding line.

Abstract: A vehicular radar system includes a plurality of transmitting sub-arrays and a transmission power divider. The plurality of transmitting sub-arrays are symmetric with respect to a symmetry axis, and the plurality of transmitting sub-arrays are parallel to the symmetry axis. The transmission power divider, coupled to the plurality of transmitting sub-arrays, is configured to apply a plurality of phases and a plurality of amplitudes to the plurality of transmitting sub-arrays. A first transmitting sub-array, among the plurality of transmitting sub-arrays and closest to the symmetry axis, and a second transmitting sub-array, among the plurality of transmitting sub-arrays and farthest away from the symmetry axis, have a phase difference in between, and the phase difference is between 120 degrees and 180 degrees.

Abstract: An array antenna forms a main beam, and the main beam is toward a beam direction. The array antenna includes a plurality of radiating elements with a plurality of central line segments, where the plurality of radiating elements are arranged along a straight line, and the straight line is connecting the plurality of central line segments; and a plurality of meanders connecting the plurality of radiating elements; where the array antenna is disposed on a first plane, the beam direction has a nonzero deviating angle with a normal direction of the first plane, and the normal direction is perpendicular to the first plane.

Abstract: A radar antenna system comprises a plurality of transmitting sub-arrays; a plurality of receiving sub-arrays; and a transceiving control unit coupled to the plurality of transmitting sub-arrays and the plurality of receiving sub-arrays, configured to control the plurality of transmitting sub-arrays and the plurality of receiving sub-arrays, such that the radar antenna system selectively operates in one of an amplitude-comparison mono-pulse mode and a phase-comparison mono-pulse mode.

Abstract: A radar and a method for enabling array antenna are proposed. The radar includes a transceiver, a multi-input multi-output (MIMO) array antenna, a phased array antenna, and a controller. The MIMO array antenna is coupled to the transceiver and includes first transmitting sub-arrays and receiving sub-arrays. The phased array antenna is coupled to the transceiver and includes second transmitting sub-arrays and the receiving sub-arrays. The controller is coupled to the transceiver and configured to to enable the first transmitting sub-arrays to form the MIMO array antenna or enable the second transmitting sub-arrays to form the phased array antenna.

Abstract: A balun filter utilized for a radio-frequency (RF) system includes a first terminal coupled to an antenna of the RF system for delivering an RF signal; a differential port has a second terminal and a third terminal for delivering a differential signal; a band pass filter coupled between the first terminal and the differential port has a plurality of resonators, each including a surrounding line substantially surrounding an area and forming a loophole on a side of the each resonator; and at least a line segment connected to the surrounding line and disposed separately within the area surrounded by the surrounding line.

Abstract: A radio-frequency transceiver system comprises a radio-frequency processing unit, a transmitting microwave network and a receiving microwave network, wherein the transmitting microwave network comprises a transmitting power divider for distributing main power of transmitting signals to two central sub-array antennas of four sub-array antennas, and the receiving microwave network comprises a receiving power divider for providing power mainly from a first input terminal and a second input terminal for a receiving route, and providing power mainly from the second input terminal and a third input terminal for another receiving route.

Abstract: An antenna includes a radiating element with a shape substantially conforming to a quadrilateral, a grounding and feed-in element, substantially surrounding the radiating element and having an opening formed near to a fourth side of the radiating element, wherein the grounding and feed-in element is electrically connected to a ground at one side of the opening and is electrically connected to a signal feed-in terminal at another side of the opening, a first connection element, having a terminal electrically connected to a first side and the fourth side of the radiating element, and another terminal electrically connected to the grounding and feed-in element, and a second connection element, having a terminal electrically connected to a third side and the fourth side of the radiating element, and another terminal electrically connected to the grounding and feed-in element.

Abstract: A radio-frequency (RF) system includes a substrate; a plurality of antenna strings, formed on a first plane of the substrate, each comprising a plurality of radiating units connected in a sequence, wherein the plurality of antenna strings are classified into a first group and a second group; a plurality of wires, formed on a second plane of the substrate, for transmitting RF signals; a plurality of connecting units, disposed in the substrate, for coupling the plurality of wires and antenna strings of the second group; a first RF processing module, for transmitting or receiving RF signals via antenna strings of the first group, and a second RF processing module, for coupling to the antenna strings of the second group through the plurality of wires and the plurality of connecting units, so as to transmit or receive RF signals via the antenna strings of the second group.

Abstract: A power divider for transmitting signals of an input terminal to a plurality of output terminals includes a rectangular microstrip line coupled to the input terminal, and a plurality of coupling units conducting the rectangular microstrip line and the plurality of output terminals by electromagnetic coupling, wherein each of the plurality of coupling units and the rectangular microstrip line are separated by a first gap, and each coupling unit includes at least one dual-L resonator disposed between the microstrip line and an output terminal, wherein the first gap and a second gap of each dual-L resonator are related to a power ratio between the input terminal and the plurality of output terminals.

Abstract: A power divider for transmitting signals of an input terminal to a plurality of output terminals includes a rectangular microstrip line coupled to the input terminal, and a plurality of coupling units conducting the rectangular microstrip line and the plurality of output terminals by electromagnetic coupling, wherein each of the plurality of coupling units and the rectangular microstrip line are separated by a first gap, and each coupling unit includes at least one dual-L resonator disposed between the microstrip line and an output terminal, wherein the first gap and a second gap of each dual-L resonator are related to a power ratio between the input terminal and the plurality of output terminals.

Abstract: A radio-frequency transceiver system comprises a radio-frequency processing unit, a transmitting microwave network and a receiving microwave network, wherein the transmitting microwave network comprises a transmitting power divider for distributing main power of transmitting signals to two central sub-array antennas of four sub-array antennas, and the receiving microwave network comprises a receiving power divider for providing power mainly from a first input terminal and a second input terminal for a receiving route, and providing power mainly from the second input terminal and a third input terminal for another receiving route.