Abstract: A signal processing method for a frequency-modulated continuous waveform (FMCW) radar system includes receiving a plurality of feedback signals from a plurality of targets and performing analog to digital conversion on the plurality of feedback signals to obtain a digital receiving signal corresponding to the plurality of feedback signals, performing a window function on the digital receiving signal to obtain a window transformation signal corresponding to the digital receiving signal, performing time-domain to frequency-domain conversion on the window transformation signal to obtain a spectrum signal of the window transformation signal, performing two beat frequency detections on the spectrum signal, and determining distances and speeds of the plurality of targets in comparison to the FMCW radar system according to results of the two beat frequency detections.

Abstract: A detachable hula hoop having waterproof reservoirs is provided with hollow arc sections each including a neck; a first connection end at a first end and including an opening, a channel, and a first recess on a surface; a plug including a cylindrical member and a head; a second connection end at a second end and including a closed member and a second recess on a surface; and a reservoir. The first recess is complimentarily disposed in the second recess to fasten the first and second connection ends together. The cylindrical member is disposed in the neck, the head urges against an annular shoulder to block the neck, and the head is urged against by the closed member.

Abstract: A compound circuit board for a radar device includes a first substrate including a plurality of trace layers having a first trace layer formed with a digital signal processing unit and an electronic control unit in a first area, a second substrate including a plurality of trace layers having a second trace layer formed with an antenna module in a second area, and a prepreg layer between the first and second substrates for connecting the first and second substrates, wherein the first area and the second area in a first projecting result generated by projecting the first trace layer on the second trace layer are substantially overlapped.

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: A detachable hula hoop having waterproof reservoirs is provided with hollow arc sections each including a neck; a first connection end at a first end and including an opening, a channel, and a first recess on a surface; a plug including a cylindrical member and a head; a second connection end at a second end and including a closed member and a second recess on a surface; and a reservoir. The first recess is complimentarily disposed in the second recess to fasten the first and second connection ends together. The cylindrical member is disposed in the neck, the head urges against an annular shoulder to block the neck, and the head is urged against by the closed member.

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 radar system comprises a transmitting device comprising a reference frequency source, for generating a reference frequency signal; a direct-digital synthesizer, coupled to the reference frequency source, for generating a synthesized frequency signal according to the reference frequency signal; a phase lock loop, coupled to the direct-digital synthesizer, for converting the synthesized frequency signal to an output signal; a transmitting antenna, coupled to the phase lock loop, for emitting the output signal to the air; and a loop switch module, coupled to the phase lock loop, for switching the phase lock loop between an open loop mode and a closed loop mode; and at least one receiving device, for receiving at least one wireless signal, and processing the at least one wireless signal according to the output signal generated by the phase lock loop.

Abstract: An unsymmetrical dipole antenna includes a grounding element, a radiating element, and a feed-in wire. The grounding element includes a first short side metal plane and a first long side metal plane. The radiating element includes a second short side metal plane and a second long side metal plane. The feed-in wire includes a metal wire, coupled to the second short side metal plane for transmitting a feed-in signal; an insulation layer, covering the metal wire; a metal weave, covering the insulation layer, having one terminal coupled to the first short side metal plane of the grounding element, and another terminal coupled to a system ground of the wireless communication device; and a protective layer, covering the metal weave. A size of the grounding element and a size of the radiating element are irrelative.

Abstract: A signal processing method for a frequency-modulated continuous waveform (FMCW) radar system includes receiving a plurality of feedback signals from a plurality of targets and performing analog to digital conversion on the plurality of feedback signals to obtain a digital receiving signal corresponding to the plurality of feedback signals, performing a window function on the digital receiving signal to obtain a window transformation signal corresponding to the digital receiving signal, performing time-domain to frequency-domain conversion on the window transformation signal to obtain a spectrum signal of the window transformation signal, performing two beat frequency detections on the spectrum signal, and determining distances and speeds of the plurality of targets in comparison to the FMCW radar system according to results of the two beat frequency detections.

Abstract: A decoupling circuit for enhancing isolation of two monopole antennas is disclosed. The two monopole antennas substantially symmetrically stand on a bottom, and a gap is formed between the two monopole antennas. The decoupling circuit includes a grounding element located on the bottom and electrically connected to a ground, a connection bar substantially perpendicular to the bottom, including a first terminal electrically connected to the grounding element, a second terminal extending to the gap, a first branch extending from the second terminal of the connection bar to a first monopole antenna of the two monopole antennas, and a second branch extending from the second terminal of the connection bar to a second monopole antenna of the two monopole antennas.

Abstract: A decoupling circuit for enhancing isolation of two antennas is disclosed. The two antennas are substantially symmetrically disposed on a substrate. The decoupling circuit includes a first and second metal strips parallel disposed between the two antennas and electrically connected to a ground, a connection strip electrically connected between terminals of the first and second metal strips, to substantially form a doorframe structure, a first comb structure comprising a plurality of metal segments parallel to each other, disposed on the substrate, electrically connected to and perpendicular to the first metal strip, and a second comb structure comprising a plurality of metal segments parallel to each other, disposed on the substrate, electrically connected to and perpendicular to the second metal strip.

Abstract: A compound circuit board for a radar device includes a first substrate including a plurality of trace layers having a first trace layer formed with a digital signal processing unit and an electronic control unit in a first area, a second substrate including a plurality of trace layers having a second trace layer formed with an antenna module in a second area, and a prepreg layer between the first and second substrates for connecting the first and second substrates, wherein the first area and the second area in a first projecting result generated by projecting the first trace layer on the second trace layer are substantially overlapped.

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: A radar system comprises a transmitting device comprising a reference frequency source, for generating a reference frequency signal; a direct-digital synthesizer, coupled to the reference frequency source, for generating a synthesized frequency signal according to the reference frequency signal; a phase lock loop, coupled to the direct-digital synthesizer, for converting the synthesized frequency signal to an output signal; a transmitting antenna, coupled to the phase lock loop, for emitting the output signal to the air; and a loop switch module, coupled to the phase lock loop, for switching the phase lock loop between an open loop mode and a closed loop mode; and at least one receiving device, for receiving at least one wireless signal, and processing the at least one wireless signal according to the output signal generated by the phase lock loop.

Abstract: A blind spot detection system comprises an alarm, capable of generating an alarm signal; a plurality of sensors, each for emitting a radio signal and receiving a reflecting signal of the emitted radio signal, to detect whether an object exists within a specific range and generate a detection result accordingly; and a control module, for receiving at least one vehicle information from the OBD system and controlling the alarm to generate the alarm signal according to the at least one vehicle information and a plurality of detection results generated by the plurality of sensors.

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 decoupling circuit for enhancing isolation of two antennas is disclosed. The two antennas are substantially symmetrically disposed on a substrate. The decoupling circuit includes a first and second metal strips parallel disposed between the two antennas and electrically connected to a ground, a connection strip electrically connected between terminals of the first and second metal strips, to substantially form a doorframe structure, a first comb structure comprising a plurality of metal segments parallel to each other, disposed on the substrate, electrically connected to and perpendicular to the first metal strip, and a second comb structure comprising a plurality of metal segments parallel to each other, disposed on the substrate, electrically connected to and perpendicular to the second metal strip.

Abstract: An automobile warning method and an automobile warning system are provided. The automobile warning method is disclosed, implemented by an automobile warning system on a vehicle, wherein the automobile warning system includes a microwave reflective detection device and a control device, including: emitting, by the microwave reflective detection device, a microwave signal for detecting whether a mobile object is present in a blind spot of the vehicle; and when the presence of the mobile object is detected, changing, by the control device, a state of a controlled device of the vehicle.

Abstract: An antenna device is provided and includes a bottom, two monopole antennas, and a cover assembled with the bottom. A projection plane is defined perpendicular to the bottom. The two monopole antennas substantially symmetrically protrude from the bottom, and a gap is formed between the two monopole antennas. Projections of the two monopole antennas on the projection plane intersect with each other. Each of the two monopole antennas includes a first frequency receiving portion adjacent to the bottom, a second frequency receiving portion, and a connection portion located between the first frequency receiving portion and the second frequency receiving portion. A slot is formed through the connection portion to adjust a received frequency of the first or second frequency receiving portion. An accommodating space is formed between the cover and the bottom to accommodate the two monopole antennas.

Abstract: A decoupling circuit for enhancing isolation of two monopole antennas is disclosed. The two monopole antennas substantially symmetrically stand on a bottom, and a gap is formed between the two monopole antennas. The decoupling circuit includes a grounding element located on the bottom and electrically connected to a ground, a connection bar substantially perpendicular to the bottom, including a first terminal electrically connected to the grounding element, a second terminal extending to the gap, a first branch extending from the second terminal of the connection bar to a first monopole antenna of the two monopole antennas, and a second branch extending from the second terminal of the connection bar to a second monopole antenna of the two monopole antennas.