A video recording and communication device includes a camera, a processor, a radar sensor, and memory. The processor executes instructions from memory to cause the device to operate the sensor in a first operational mode in which the camera is maintained in a low-power mode. The processor further detects, using the sensor in the first mode, possible motion of an object within a threshold distance from the sensor. Responsive to the detecting, the processor transitions the sensor from the first mode to a second operational mode. The second mode consumes more power than the first mode. The processor determines, using the radar sensor in the second mode, that the possible motion of the object occurred in a region of interest, in response to which, it transitions the sensor from the second mode to a third operational mode. The third mode consumes more power mode than the second mode.

A video recording and communication device includes a camera, a processor, a radar sensor, and memory. The processor executes instructions from memory to cause the device to operate the sensor in a first operational mode in which the camera is maintained in a low-power mode. The processor further detects, using the sensor in the first mode, possible motion of an object within a threshold distance from the sensor. Responsive to the detecting, the processor transitions the sensor from the first mode to a second operational mode. The second mode consumes more power than the first mode. The processor determines, using the radar sensor in the second mode, that the possible motion of the object occurred in a region of interest, in response to which, it transitions the sensor from the second mode to a third operational mode. The third mode consumes more power mode than the second mode.

A method and system improve on the accuracy of detecting the presence of people in a room. Aspects of the embodiments may be used for occupancy sensors by monitoring occupant physiological movements. In an embodiment, a Doppler radar sensor may be used to measure the occupant-related physiological signals, calculate the Riemann integral (RI) of the occupants' cardiopulmonary movement displacement, body movement index (BMI), and amplitude difference accumulation (ADA) of the body movement. A determination for detection of occupants may be by adaptive thresholding.

A method and system improve on the accuracy of detecting the presence of people in a room. Aspects of the embodiments may be used for occupancy sensors by monitoring occupant physiological movements. In an embodiment, a Doppler radar sensor may be used to measure the occupant-related physiological signals, calculate the Riemann integral (RI) of the occupants' cardiopulmonary movement displacement, body movement index (BMI), and amplitude difference accumulation (ADA) of the body movement. A determination for detection of occupants may be by adaptive thresholding.

A radar antenna calibration method includes: forming a detection matrix from signals detected by an arrangement of receive antennas in response to chirps transmitted by an arrangement of transmit antennas, the detection matrix having multiple rows corresponding to the chirps, multiple columns corresponding to a signal sample, and multiple planes corresponding the receive antennas; deriving a range matrix by performing a frequency transform on a portion of each row of the detection matrix; extracting a slice of the range matrix, with different rows of the slice being associated with different chirps and with different receive antennas; deriving a velocity matrix from the extracted slice by performing a frequency transform on a portion of each column of the extracted slice; analyzing the velocity matrix to determine a current peak width; and adjusting, based on the current peak width, phase shifts associated with one or more of the receive antennas.

A radar antenna calibration method includes: forming a detection matrix from signals detected by an arrangement of receive antennas in response to chirps transmitted by an arrangement of transmit antennas, the detection matrix having multiple rows corresponding to the chirps, multiple columns corresponding to a signal sample, and multiple planes corresponding the receive antennas; deriving a range matrix by performing a frequency transform on a portion of each row of the detection matrix; extracting a slice of the range matrix, with different rows of the slice being associated with different chirps and with different receive antennas; deriving a velocity matrix from the extracted slice by performing a frequency transform on a portion of each column of the extracted slice; analyzing the velocity matrix to determine a current peak width; and adjusting, based on the current peak width, phase shifts associated with one or more of the receive antennas.

An occupancy detection apparatus has a switch, a first antenna, a second antenna, a transmitter, and a motion detection circuit. The occupancy detection apparatus monitors for a first motion in a first region using the first antenna using a first motion detection parameter. When no first motion is sensed by the monitoring using the first antenna, the occupancy detection apparatus monitors for a second motion in a second region using the second antenna using a second motion detection parameter. When no second motion is sensed by monitoring using the second antenna, the occupancy detection apparatus designates a space, which encompasses the second region, as unoccupied. The first region and the second region overlap one another, and the first motion detection parameter is different from the second motion detection parameter.

An occupancy detection apparatus has a switch, a first antenna, a second antenna, a transmitter, and a motion detection circuit. The occupancy detection apparatus monitors for a first motion in a first region using the first antenna using a first motion detection parameter. When no first motion is sensed by the monitoring using the first antenna, the occupancy detection apparatus monitors for a second motion in a second region using the second antenna using a second motion detection parameter. When no second motion is sensed by monitoring using the second antenna, the occupancy detection apparatus designates a space, which encompasses the second region, as unoccupied. The first region and the second region overlap one another, and the first motion detection parameter is different from the second motion detection parameter.

A method for detecting a living being on a seat of a vehicle, further relating to a detection arrangement and to a vehicle. The method may include emitting electromagnetic waves at predetermined frequency or at a predetermined frequency band towards the seat by an electromagnetic radiator, receiving electromagnetic waves reflected on a surface by a sensor, detecting an object on the seat from a transit time of the emitted and the reflected electromagnetic waves between the radiator, the surface and the sensor by a detection device, detecting movements of the object from the reflected electromagnetic waves by the detection device if an object has been detected, determining from the detected movements of the object whether the detected object is a living being, and outputting a detection signal by way of the detection device if it has been determined that the detected object is a living being.

Systems and methods for detecting and monitoring human breathing, respiration, and heart rate using statistics about the wireless channel between two or more connected devices. A user is monitored for identifying patterns in the user's behavior that may allow the system to alert a caregiver to deviations in the user behavior that may be indicative of a potential issue, such as depression. A presence may further detected in a sensing area through the detection of spectral components in the breathing frequency range of comprises user includes transforming phase difference between spatial streams and amplitude of the samples representing frequency response of the channel for any frequency value into frequency domain to perform frequency analysis. Statistical analysis may be performed on the frequency space provided by the transformation. Micro motions may also be detected by detecting presence in a sensing area through the detection of spectral components in the micro motion frequency range.