Abstract: A method of detecting a life includes receiving an echo signal including an in-phase component and a quadrature component, performing a preprocessing procedure on the echo signal to generate a preprocessed signal, generating, according to the preprocessed signal, complex conjugate data associated with the in-phase component and the quadrature component, performing a first time-domain-to-frequency-domain transform on the complex conjugate data to generate Doppler spectrogram data comprising a plurality of positive velocity energies and a plurality of negative velocity energies, generating combined Doppler spectrogram data according to the plurality of positive velocity energies and the plurality of negative velocity energies, performing a second time time-domain-to-frequency-domain transform on the combined Doppler spectrogram data to generate spectrum data, and determining whether a life is detected according to the spectrum data.

Abstract: A radar signal device includes an antenna unit, a transmission circuit and a reception circuit. The antenna unit is used to concurrently transmit a transmission signal and receive a reception signal. The antenna unit includes a metal layer, a first feed structure and a second feed structure. An opening is formed on the metal layer. A first projection of the first feed structure on the metal layer at least partially overlaps with the opening. A second projection of the second feed structure on the metal layer at least partially overlaps with the opening. The antenna unit forms a first radiation pattern used to transmit the transmission signal and a second radiation pattern used to receive the reception signal. An angle between a co-polarized electric field direction of the first radiation pattern and a co-polarized electric field direction of the second radiation pattern is between 45 degrees and 135 degrees.

Abstract: A transceiver includes an antenna configured to transmit a first wireless signal based on a transmission signal and receive a second wireless signal, the second wireless signal including a reflected first wireless signal from an object and the antenna transmitting the first wireless signal and receiving the second wireless signal at the same time. A transmission circuit is configured to generate the transmission signal and output the transmission signal to a first side of the antenna. A reception circuit is configured to receive a reception signal from a second side of the antenna, the antenna outputting the reception signal based on the second wireless signal. The first side is different from the second side.

Abstract: An antenna apparatus is provided. The antenna apparatus includes a cavity element, a radiating element, and a feeding element. The cavity element includes an opening. The radiating element is located within the opening and disposed at a conductive layer. An outline of the radiating element and the opening form a surrounding slot. An imagining rectangle has four sides respectively abutted against an external outline of the surrounding slot. The feeding element is disposed at the same conductive layer. The feeding element includes a first section and a second section. A coupling distance is provided between the first section and the radiating element. A tail end of the first section is an open circuit. A shift distance is provided between the second section and a central line of the imagining rectangle.

Abstract: A motion detecting system includes a microwave motion sensor and an MCU. After detecting a motion with a first configuration, the microwave motion sensor is configured to operate with a second configuration for detecting another motion. The MCU is configured to operate in different modes for performing corresponding actions based on whether the microwave motion sensor can detect motions with different configurations, thereby reducing power consumption. The present motion detecting system can determine the type of motions detected by the microwave motion sensor, thereby reducing the false alarm rate.

Abstract: A switch device includes a first radio-frequency (RF) terminal, a second RF terminal, a first transistor, a second transistor, and a variable resistance element. The first transistor includes a first terminal coupled to the first RF terminal, a second terminal, and a control terminal coupled to a control signal terminal providing a control signal. The second transistor includes a first terminal coupled to the second terminal of the first transistor, a second terminal coupled to the second RF terminal, and a control terminal. The variable resistance element is coupled between the second terminal of the first transistor and a bias voltage terminal. When the first transistor and the second transistor are in a transient state, the variable resistance element provides a lower resistance. When the first transistor and the second transistor are in an ON state, the variable resistance element provides a higher resistance.

Abstract: An acoustic wave device includes a piezoelectric substrate, a transducer, and a depression. The transducer is disposed on a surface of the piezoelectric substrate, and includes a first bus bar, a first electrode, a second bus bar, and a second electrode. The first bus bar and the second bus bar extend along a second direction. The first electrode has a first end and extends from the first bus bar along a first direction. The first electrode and the second electrode are spaced apart from each other, and a gap is formed between the first end of the first electrode and an edge of the second bus bar. The depression is formed in the piezoelectric substrate and is depressed from the surface of the piezoelectric substrate. The first end of the first electrode is continuously joined to a sidewall of the depression along a depth direction.

Abstract: A radio frequency (RF) device and a multi-band matching circuit thereof are provided. The multi-band matching circuit includes an inductance circuit, a first capacitance circuit, an inductor, and a second capacitance circuit. A first terminal of the inductance circuit is coupled to a RF signal input terminal of the multi-band matching circuit. A first terminal of the first capacitance circuit is coupled to a second terminal of the inductance circuit. A first terminal of the inductor and a first terminal of the second capacitance circuit are coupled to a second terminal of the first capacitance circuit. A second terminal of the inductor is coupled to a first reference voltage. A second terminal of the second capacitance circuit is coupled to a second reference voltage. The second capacitance circuit is controlled by a single-bit control signal to change a capacitance value of the second capacitance circuit.

Abstract: A power detector includes a detection circuit and a bias circuit. The detection circuit is used to receive an input signal and output a power indication signal. The bias circuit includes a first impedance unit, a second impedance unit and a transistor. The transistor includes a first terminal and a control terminal coupled to the first impedance unit, and a second terminal. The second impedance unit is coupled between the first terminal of the transistor and an output terminal of the bias circuit, or between the second terminal of the transistor and a second terminal of the bias circuit. The output terminal of the bias circuit is coupled to an input terminal of the detection circuit, and is used to output a bias signal.

Abstract: An acoustic wave device includes a piezoelectric substrate and a transducer. The piezoelectric substrate has a surface. The transducer is disposed on the surface. The transducer includes a first electrode, a second electrode, and at least one protrusion. The first electrode extends along a first direction and has a first end. The second electrode extends along the first direction and has a second end. The first electrode and the second electrode are spaced apart from each other along a second direction. The at least one protrusion is disposed at the first end of the first electrode. The at least one protrusion extends along the first direction and partially obstruct the first end.

Abstract: A transceiver includes an antenna configured to transmit a first wireless signal based on a transmission signal and receive a second wireless signal, the second wireless signal including a reflected first wireless signal from an object and the antenna transmitting the first wireless signal and receiving the second wireless signal at the same time. A transmission circuit is configured to generate the transmission signal and output the transmission signal to a first side of the antenna. A reception circuit is configured to receive a reception signal from a second side of the antenna, the antenna outputting the reception signal based on the second wireless signal. The first side is different from the second side.

Abstract: A compensation circuit includes a resistor-capacitor circuit and a control circuit. The resistor-capacitor circuit is used to generate a first voltage when a reference signal is in a first state, and generate a second voltage and a third voltage when the reference signal is in a second state. The resistor-capacitor circuit includes a first resistor-capacitor sub-circuit and a second resistor-capacitor sub-circuit. The first resistor-capacitor sub-circuit and the second resistor-capacitor sub-circuit are coupled to the control circuit, and operate simultaneously to compute an ON time of a front end module. The control circuit is coupled to the resistor-capacitor circuit, and is used to acquire the ON time according to the first voltage, the second voltage, and the third voltage, and includes an adjustment circuit used to generate a bias signal according to the ON time, and output the bias signal to the front end module.

Abstract: An antenna apparatus is provided. The antenna apparatus includes a cavity element, a radiating element, and a feeding element. The cavity element includes an opening. The radiating element is located in the opening and is disposed at a conductive layer. An outline of the radiating element and the opening form a surround slot. An imaginary rectangle has four sides respectively abutted against an external outline of the surround slot. The feeding element is disposed at another parallel conductive layer. The feeding element includes two sections. There is a coupling spacing is between a section and the radiating element to feed into the radiating element through electric field coupling. A tail end of the section is an open circuit. Another section is an initial section of the feeding element inserted into the opening. There is a shifting spacing between the another section and a central line of the imaginary rectangle.

Abstract: The switch device includes a first circuit. The first circuit has a first end coupled between a first terminal and a second terminal, and the first circuit has the second end coupled between the first terminal and the second terminal or coupled to a third terminal. The first circuit includes a first switch and a second switch. The first switch is coupled between the first end and the second end of the first circuit and is turned on or off according to a first control signal. The second switch is connected to the first switch in parallel and is turned on or off according to a second control signal. The first switch and the second switch include transistors of the same type. In a surge protection mode, the second switch is turned on to dissipate the surge current.

Abstract: The present invention discloses a bias compensation circuit. The bias compensation circuit includes a detecting circuit, including a diode-connected transistor circuit, with a first end for receiving a first current, and a second end coupled to a first reference voltage end; and a first diode circuit, with a first end for receiving a second current, and a second end coupled to the first reference voltage end; wherein the detecting circuit provides a first voltage level according to the diode-connected transistor circuit, and provides a second voltage level according to the first diode circuit; a voltage-current converting circuit, coupled to the detecting circuit, for generating a first reference current according to the first voltage level and the second voltage level; and a bias circuit, coupled to the voltage-current converting circuit, for receiving the first reference current, to provide a bias voltage level according to the first reference current.

Abstract: A matching circuit includes an input terminal, an output terminal, a first impedance component, a first set of switching devices, a second impedance component, a second set of switching devices and a controller. The first impedance component includes a first terminal coupled between the input terminal and the output terminal, and a second terminal. The first set of switching devices is coupled to the second terminal of the first impedance component, the controller and a reference terminal. The second impedance component includes a first terminal coupled between the second terminal of the first impedance component and the first set of switching devices, and a second terminal. The second set of switching devices is coupled to the second terminal of the second impedance component, the controller and the reference terminal. The controller controls the first set of switch devices and the second set of switch devices according to a detection signal.

Abstract: A front end module includes a first radio frequency (RF) terminal, a second RF terminal, a third RF terminal, a transmission path and a reception path. The transmission path is formed between the first RF terminal and the third RF terminal. The reception path is formed between the first RF terminal and the second RF terminal. The reception path includes a first set of switches, a second set of switches, a third set of switches and an amplifier. An amplifier is coupled to the second set of switches and the second RF terminal. The third set of switches is coupled to the first set of switches and the second RF terminal. When a transmission signal is transmitted to the first RF terminal via the transmission path, the first set of switches, the second set of switches and the third set of switches are turned off.

Abstract: A switch device includes a first radio-frequency (RF) terminal, a second RF terminal, a first transistor, a second transistor, and a variable resistance element. The first transistor includes a first terminal coupled to the first RF terminal, a second terminal, and a control terminal coupled to a control signal terminal providing a control signal. The second transistor includes a first terminal coupled to the second terminal of the first transistor, a second terminal coupled to the second RF terminal, and a control terminal. The variable resistance element is coupled between the second terminal of the first transistor and a bias voltage terminal. When the first transistor and the second transistor are in a transient state, the variable resistance element provides a lower resistance. When the first transistor and the second transistor are in an ON state, the variable resistance element provides a higher resistance.

Abstract: An amplifier circuit includes an amplifier, a detector and an adjustment circuit. The amplifier includes a first transistor and a bias voltage terminal. The first transistor includes a first terminal coupled to a first reference voltage terminal, a second terminal coupled to a second reference voltage terminal, and a control terminal coupled to the bias voltage terminal of the amplifier. The second transistor includes a first terminal coupled to a third reference voltage terminal and the detector, and a second terminal coupled to the second reference voltage terminal. The detector outputs a detection signal related to a characteristic parameter of the second transistor. The adjustment circuit is coupled to the detector and the bias voltage terminal of the amplifier for performing an adjustment operation according to the detection signal.

Abstract: A radio frequency switch has an antenna end, a first signal end for transmitting a first radio frequency signal, a second signal end for transmitting a second radio frequency signal, a third signal end for transmitting a third radio frequency signal, a first series path having a first switch, a second series path having a second switch, a third series path having a third switch, a first shunt path coupled between the first signal end and a node, a second shunt path coupled between the second signal end and the node, a common path coupled between the node and a first reference voltage end, and a third shunt path coupled between the third signal end and a second reference voltage end. The first series path and the second series path are connected to a common ground pad via the common path.