Abstract: A multiple-target vital sign detector includes a self-injection-locked oscillator (SILO), a chirp up/down converter, a frequency demodulator and a multiple-target vital sign processor. The chirp up/down converter performs conversion from an oscillation signal generated by the SILO to a frequency-modulated continuous wave (FMCW) signal to detect an area and from a received FMCW signal reflected from the area to an injection signal, while the SILO is injected with the injection signal to enter a self-injection-locked state. The locations and vital signs of multiple subjects are extracted from the oscillation signal using the frequency demodulator and the multiple-target vital sign processor. The objective of using the SILO is to improve the sensitivity of the FMCW detection process so as to more effectively distinguish the vital signs of multiple subjects at different locations.

Abstract: A phased-array Doppler radar includes a two-way splitter, a transmit antenna, a receive antenna array, an ILO, a demodulation unit and a digital signal processing unit. A reference signal is split by the two-way splitter to the transmit antenna for transmission to targets and the ILO for injection locking. Signals reflected by the targets are received by the receive antenna array as received signals. An injection-locked signal generated by the ILO and the received signals received by the receive antenna array are delivered to the demodulation unit. The received signals are demodulated into baseband I/Q signals by the demodulation unit that uses the injection-locked signal as a local oscillator signal. The baseband I/Q signals are processed by the digital signal processing unit to obtain a digital beamforming pattern.

Abstract: A SIL monopulse radar includes a self-injection-locking oscillator (SILO), a transmit antenna, two receive antennas, a hybrid coupler, a first demodulator, a second demodulator and a processor. The transmit antenna transmits the oscillation signal of the SILO to object. The two receive antennas receive a reflected signal from the object as a first echo signal and a second echo signal. The hybrid coupler outputs a difference signal and a sum signal. The difference signal is injected into the SILO. The first demodulator frequency-demodulates the oscillation signal to produce a first demodulated signal. The second demodulator phase-demodulates the sum signal by using the oscillation signal as a reference signal to produce a second demodulated signal. The processor processes the first and second demodulated signals to produce a monopulse ratio signal. The SIL monopulse radar can identify the posture and motion of a human body by analyzing the monopulse ratio signal.

Abstract: In a noncontact vital sign sensing device of the present invention, a gain detector is provided to detect a gain between an oscillation signal and a received signal. Gain detection can cancel out the amplitude noise of an oscillator such that frequency information of vital sign(s) of a subject can be extracted from the gain without null-point issue, and vital sign(s) of the subject located at any position within sensing range can be detected.

Abstract: A digital self-injection-locked (SIL) radar includes a digital SIL oscillator, a wireless signal transceiver and a digital frequency demodulator. The digital SIL oscillator generates a digital output signal. The wireless signal transceiver is electrically connected to the digital SIL oscillator to convert the digital output signal into a wireless signal for transmission to a target, receives a reflected signal from the target, and converts the reflected signal into a digital injection signal for injection into the digital SIL oscillator. Accordingly, the digital SIL oscillator operates in an SIL state and generates a digital oscillation signal. The digital frequency demodulator is electrically connected to the digital SIL oscillator to receive and demodulate the digital oscillation signal into a digital demodulation signal.

Abstract: A vital-sign radar sensor uses wireless internet signals to detect vital signs. It includes a first and second demodulation unit to demodulate an incident and reflected wireless internet signal with an injection-locked oscillator into a first and second demodulated signal, respectively. The combined use of the first and second demodulated signals can eliminate the influence of communication modulation on the extraction process of a Doppler shift due to vital signs. Moreover, the vital-sign radar sensor is a receive-only device so that it won't cause interference to ambient wireless communication networks.

Abstract: A vital-sign radar sensor uses wireless internet signals to detect vital signs. It includes a first and second demodulation unit to demodulate an incident and reflected wireless internet signal with an injection-locked oscillator into a first and second demodulated signal, respectively. The combined use of the first and second demodulated signals can eliminate the influence of communication modulation on the extraction process of a Doppler shift due to vital signs. Moreover, the vital-sign radar sensor is a receive-only device so that it won't cause interference to ambient wireless communication networks.

Abstract: A phase-tracking self-injection-locked (SIL) radar includes an SIL oscillator, a phase-tracking SIL loop and a frequency-locked loop. The SIL oscillator generates an electrical oscillation signal and receives an electrical injection signal related to the electrical oscillation signal for self-injection locking. The phase-tracking SIL loop receives the electrical oscillation signal and outputs the electrical injection signal to the SIL oscillator with a constant phase difference between the electrical oscillation signal and the electrical injection signal. The frequency-locked loop receives the electrical oscillation signal and produces an electrical control signal to control the phase-tracking SIL loop or the SIL oscillator for eliminating the frequency shift of the SIL oscillator caused by the phase-tracking SIL loop.

Abstract: A phase-tracking self-injection-locked (SIL) radar includes an SIL oscillator, a phase-tracking SIL loop and a frequency-locked loop. The SIL oscillator generates an electrical oscillation signal and receives an electrical injection signal related to the electrical oscillation signal for self-injection locking. The phase-tracking SIL loop receives the electrical oscillation signal and outputs the electrical injection signal to the SIL oscillator with a constant phase difference between the electrical oscillation signal and the electrical injection signal. The frequency-locked loop receives the electrical oscillation signal and produces an electrical control signal to control the phase-tracking SIL loop or the SIL oscillator for eliminating the frequency shift of the SIL oscillator caused by the phase-tracking SIL loop.

Abstract: A phased-array Doppler radar includes a two-way splitter, a transmit antenna, a receive antenna array, an ILO, a demodulation unit and a digital signal processing unit. A reference signal is split by the two-way splitter to the transmit antenna for transmission to targets and the ILO for injection locking. Signals reflected by the targets are received by the receive antenna array as received signals. An injection-locked signal generated by the ILO and the received signals received by the receive antenna array are delivered to the demodulation unit. The received signals are demodulated into baseband I/Q signals by the demodulation unit that uses the injection-locked signal as a local oscillator signal. The baseband I/Q signals are processed by the digital signal processing unit to obtain a digital beamforming pattern.

Abstract: A digital self-injection-locked (SIL) radar includes a digital SIL oscillator, a wireless signal transceiver and a digital frequency demodulator. The digital SIL oscillator generates a digital output signal. The wireless signal transceiver is electrically connected to the digital SIL oscillator to convert the digital output signal into a wireless signal for transmission to a target, receives a reflected signal from the target, and converts the reflected signal into a digital injection signal for injection into the digital SIL oscillator. Accordingly, the digital SIL oscillator operates in an SIL state and generates a digital oscillation signal. The digital frequency demodulator is electrically connected to the digital SIL oscillator to receive and demodulate the digital oscillation signal into a digital demodulation signal.

Abstract: A vital-sign radar sensor using wireless frequency-locked loop includes a voltage-controlled oscillator (VCO), an antenna component, a mixer, a loop filter and a frequency demodulation component. The VCO outputs an oscillation signal to the antenna component via a output port, the antenna component transmits the oscillation signal to a subject as a transmitted signal and receives a reflected signal from the subject as a received signal, the mixer receives and mix the oscillation signal and the received signal into a mixed signal, the loop filter receives and filter the mixed signal to output a filtered signal, the filtered signal is delivered to the VCO via a tuning port, the frequency demodulation component receives and demodulates the oscillation signal to output a vital-sign signal.

Abstract: A signal demodulation device includes an IQ mixer, a differential element and a signal processor. The IQ mixer is configured to output a first mixed signal and a second mixed signal. The differential element is electrically connected to the IQ mixer for receiving the first and second mixed signals and configured to differentiate the first and second mixed signals and output a first derivative signal and a second derivative signal. The signal processor is electrically connected to the differential element for receiving the first and second derivative signals and configured to demodulate the first and second derivative signals and output a first demodulated signal.

Abstract: A multiple-target vital sign detector includes a self-injection-locked oscillator (SILO), a chirp up/down converter, a frequency demodulator and a multiple-target vital sign processor. The chirp up/down converter performs conversion from an oscillation signal generated by the SILO to a frequency-modulated continuous wave (FMCW) signal to detect an area and from a received FMCW signal reflected from the area to an injection signal, while the SILO is injected with the injection signal to enter a self-injection-locked state. The locations and vital signs of multiple subjects are extracted from the oscillation signal using the frequency demodulator and the multiple-target vital sign processor. The objective of using the SILO is to improve the sensitivity of the FMCW detection process so as to more effectively distinguish the vital signs of multiple subjects at different locations.

Abstract: In a vital sign sensor of the present invention, an antenna assembly radiates an oscillation signal generated by a SIL oscillator to an object in a form of a wireless signal and receives a reflected signal from the object, and the reflected signal can have the SIL oscillator injection-locked. The wireless signal radiated from the antenna assembly is transmitted to a demodulator for demodulation such that the vital signs of the object can be obtained. Additionally, an isolator of the antenna assembly is provided to prevent the SIL oscillator from receiving a clutter reflected from the demodulator and an environment where the demodulator is placed. As a result, the clutter can't influence the vital sign detection of the object.

Abstract: A 3-D path detection system includes an image capture device, a radar device and a computing module. The image capture device is provided to produce a dynamic image for calculating the x- and y-direction (transverse) pixel-value displacements according to a captured moving object image. The radar device is configured to transmit an input wireless signal to a moving object and receive a reflection signal from the moving object, and is configured to calculate a z-direction (longitudinal) displacement of the moving object according to a Doppler shift in the reflection signal. The computing module is configured to construct a 3-D path of the moving object according to the x- and y-direction pixel-value displacements of the moving object image and the z-direction displacement of the moving object.

Abstract: A signal demodulation device includes an IQ mixer, a differential element and a signal processor. The IQ mixer is configured to output a first mixed signal and a second mixed signal. The differential element is electrically connected to the IQ mixer for receiving the first and second mixed signals and configured to differentiate the first and second mixed signals and output a first derivative signal and a second derivative signal. The signal processor is electrically connected to the differential element for receiving the first and second derivative signals and configured to demodulate the first and second derivative signals and output a first demodulated signal.

Abstract: An active phase switchable array includes a plurality of antenna elements and a bias circuit. Each of the radar elements includes an antenna, a power coupling network and an injection-locked oscillator (ILO), and each of the antenna elements is coupled with each other through the power coupling networks for operating the ILO of each of the antenna elements in self- and mutual-injection-locked states. The antenna elements in self-injection-locked state are utilized to detect the vital signs of subjects, and the antenna elements in mutual-injection-locked state are utilized to produce phase difference between the radiating signals of the antenna elements for forming a beam. As a result, the active phase switchable array can simultaneously detect the vital signs of multiple subjects.

Abstract: A vital sign detection system includes a radar device, a nonreciprocal network, a first antenna and a second antenna. An output signal from the radar device is delivered to the first antenna via the nonreciprocal network and then transmitted to a first side of a biological subject via the first antenna. A first reflection signal from the first side of the biological subject is received by the first antenna and then delivered to the second antenna via the nonreciprocal network and then transmitted to a second side of the biological subject via the second antenna. A second reflection signal from the second side of the biological subject is received by the second antenna and then delivered to the radar device via the nonreciprocal network for vital sign detection with random body movement cancellation.

Abstract: In a vital sign sensor of the present invention, an antenna assembly radiates an oscillation signal generated by a SIL oscillator to an object in a form of a wireless signal and receives a reflected signal from the object, and the reflected signal can have the SIL oscillator injection-locked. The wireless signal radiated from the antenna assembly is transmitted to a demodulator for demodulation such that the vital signs of the object can be obtained. Additionally, an isolator of the antenna assembly is provided to prevent the SIL oscillator from receiving a clutter reflected from the demodulator and an environment where the demodulator is placed. As a result, the clutter can't influence the vital sign detection of the object.