Abstract: An illustrative sensor controller includes: a transmitter, a first receiver, a second receiver, a propagation speed circuit, and a level circuit. The transmitter provides a drive signal to an ultrasonic sending transducer to generate an acoustic burst. The first receiver receives a first response signal from a first ultrasonic receiving transducer. The second receiver receives a second response signal from a second ultrasonic receiving transducer at a predetermined distance from the ultrasonic sending transducer. The propagation speed circuit is configured to detect a direct arrival of the acoustic burst in the second response signal and to measure a corresponding propagation speed. The level circuit detects a reflected arrival of the acoustic burst in the first response signal, measures a corresponding time of flight, and derives a fluid level based on the time of flight and the propagation speed.

Abstract: An illustrative sensor controller includes: a transmitter, a receiver, a time-of-flight circuit, and a phase shift circuit. The transmitter is configured to provide a drive signal to an ultrasonic sending transducer to generate an acoustic burst. The receiver is configured to receive a response signal from an ultrasonic receiving transducer. The time-of-flight circuit is configured to detect an arrival of the acoustic burst in the response signal and to measure a first time of flight associated with that arrival. The phase shift circuit is configured to measure a phase shift of the acoustic burst in the response signal and to determine a second time of flight corresponding to the phase shift.

Abstract: Ultrasonic sensors, sensor controllers, and sensor control methods are provided with self-cleaning functionality. An illustrative method includes: driving a piezoelectric transducer to generate a short acoustic burst for obstacle detection or distance measurement; obtaining a receive signal to monitor for reflections of the short acoustic burst; and operating to clean the sensor by driving the piezoelectric transducer to generate a long acoustic burst at a resonant frequency of the piezoelectric transducer. The method may be implemented by a sensor controller having a transmitter configured to drive the piezoelectric transducer, a receiver coupled to the piezoelectric transducer and a microphone to detect a reflection of the acoustic burst within a measurement interval associated with the acoustic burst; and a microcontroller configured to control a length of the acoustic burst.

Abstract: Accordingly, there is disclosed herein host device and bus communication method that enables fast sensor device reinitialization that minimizes outage time associated with an unexpected device reset. One illustrative bus communication method includes: providing each of one or more slave devices with a dynamically-determined bus address; querying each of the dynamically-determined bus addresses to obtain a unique device identifier associated with that dynamically-determined bus address; receiving a sequence of data frames each having time-division multiplexed data from the one or more slave devices; and between data frames in the sequence, checking to determine whether any of the one or more slave devices has been reset.

Abstract: An obstacle monitoring system includes a transducer that receives an ultrasonic echo from an obstacle and generates a signal based on the echo. The system further includes a controller coupled to the transducer that is calibrated based on a frequency response of the transducer and a coupling circuit. The system further includes circuitry generating a damping current, controlled by the controller, that reduces or eliminates reverberation of the transducer.

Abstract: Illustrative sensor controllers, sensors, sensing systems, and sensing methods, may enable cost-efficient implementation of ADAS (advanced driver-assistance system) features with hidden sensors. As one example, an illustrative sensing method includes: transmitting an acoustic burst through a surface over an ultrasonic transducer; receiving an acoustic signal with a MEMS (micro-electromechanical systems) microphone, the MEMS microphone representing the acoustic signal as an electrical receive signal; and processing the electrical receive signal to detect a reflection of the acoustic burst.

Abstract: illustrative vehicles, systems, and methods adapt ultrasonic sensing arrays for close-range communication with, e.g., smart devices, parking infrastructure, and other vehicles. As one example, an illustrative vehicle includes: one or more ultrasonic sensors configured for proximity sensing; and a controller configured to use the one or more ultrasonic sensors to receive an acoustic signal from a smart device. As another example, an illustrative vehicle includes one or more microphones configured for at least one of noise cancellation, voice control, emergency vehicle detection, and proximity sensing; and a controller configured to use the one or more microphones to receive an acoustic signal from a smart device, the acoustic signal being in the frequency range between 18 kHz and 25 kHz, inclusive.

Abstract: An illustrative controller includes: a transmitter to drive an acoustic transducer to generate a first acoustic burst and a second acoustic burst; a receiver coupled to the acoustic transducer to sense a first response to the first acoustic burst and a second response to the second acoustic burst; and a processing circuit to derive output data from the first and second responses in part by determining an offset frequency difference between the first and second responses, wherein the first acoustic burst has a first characteristic frequency and the second acoustic burst has a second characteristic frequency different from the first characteristic frequency.

Abstract: Breathing sensors, sensing methods, and vehicle occupant monitoring systems may employ ultrasonic transducers. One illustrative sensing method includes: sensing an acoustic transducer's responses to a series of acoustic bursts emitted in a vehicle's cabin; differencing pairs of said responses to obtain difference signals; converting the difference signals into magnitude signals; performing peak detection on each of the magnitude signals to obtain at least one peak amplitude; and providing a breathing signal based on the at least one peak amplitude. The breathing signal may be an occupancy detection flag, an occupant position, a breathing frequency, and/or any combination thereof.

Abstract: Secure serial bus communication methods and devices suitable for automotive applications. An illustrative integrated circuit includes: a scrambler configured to process data packets into masked data packets using a configuration or an initial state derived by proprietary processing of a seed value stored in the clear or received via a bus; and a digital-to-analog converter configured to send the masked data packets via the bus.

Abstract: Secure serial bus communication methods and devices suitable for automotive applications. An illustrative sensor IC includes: a sensor controller that operates a transducer to obtain measurement data formattable as data packets; a scrambler that masks each data packet with a scrambling operation before that data block is sent via a serial bus to a bus controller device, said scrambling operation having a secret configuration and/or secret initial state; and an integrated circuit component that operates on a seed value to derive the secret configuration and/or secret initial state.

Abstract: An illustrative controller includes: a transmitter to drive an acoustic transducer to generate a first acoustic burst and a second acoustic burst; a receiver coupled to the acoustic transducer to sense a first response to the first acoustic burst and a second response to the second acoustic burst; and a processing circuit to derive output data from the first and second responses in part by determining an offset frequency difference between the first and second responses, wherein the first acoustic burst has a first characteristic frequency and the second acoustic burst has a second characteristic frequency different from the first characteristic frequency.

Abstract: Breathing sensors, sensing methods, and vehicle occupant monitoring systems may employ ultrasonic transducers. One illustrative sensing method includes: sensing an acoustic transducer's responses to a series of acoustic bursts emitted in a vehicle's cabin; differencing pairs of said responses to obtain difference signals; converting the difference signals into magnitude signals; performing peak detection on each of the magnitude signals to obtain at least one peak amplitude; and providing a breathing signal based on the at least one peak amplitude. The breathing signal may be an occupancy detection flag, an occupant position, a breathing frequency, and/or any combination thereof.

Abstract: An illustrative controller includes: a transmitter to drive an acoustic transducer to generate a first acoustic burst and a second acoustic burst; a receiver coupled to the acoustic transducer to sense a first response to the first acoustic burst and a second response to the second acoustic burst; and a processing circuit to derive output data from the first and second responses in part by determining an offset frequency difference between the first and second responses, wherein the first acoustic burst has a first characteristic frequency and the second acoustic burst has a second characteristic frequency different from the first characteristic frequency.

Abstract: A smart ultrasonic integrated-circuit that allows at least one MEMS device to be combined with a piezoelectric transducer in a sensor array module. The sensor array module is capable of additional functionality for an advanced driver assistance system. For example, the MEMS device can add functionality because its wide bandwidth allows for simultaneous detection of audio signals and ultrasonic signals. Accordingly, the sensor array module may provide dual-mode (audio and ultrasonic) sensing in a single module. Additionally the size/cost of a MEMS device allows for the use of a two-dimensional array for receiving ultrasonic echoes which can add a dimension to the ultrasonic range detection for a vehicle.

Abstract: Methods and devices provide for enhanced robustness via graceful packet error detection and packet retransmission. One illustrative sensing method includes: generating a voltage pulse on a signal conductor coupled to a sensor array including one or more active sensors, the voltage pulse representing a broadcast read command (BRC) that defines a frame of one or more time-division-multiple-access (TDMA) slots, one slot for each active sensor to send a data packet; performing current sensing on the signal conductor to receive the data packet from each of the one or more active sensors; determining whether each said data packet is received error free; and requesting retransmission of each said data packet not received error free.

Abstract: Various sensors, sensor controllers, and sensing methods are suitable for use in a multi-channel ultrasonic sensor array such as those used in systems for parking assistance, blind spot monitoring, and driver assistance. One illustrative acoustic sensing method includes: driving an acoustic transducer to send acoustic bursts each including an up-chirp in a first frequency band and a down-chirp in a second frequency band; receiving echo signals responsive to the acoustic bursts from the transducer; and using the echo signals to determine a distance or time of flight from the transducer. Another acoustic sensing method includes: driving an acoustic transducer to send acoustic bursts each including a concurrent up-chirp and down-chirp; receiving echo signals responsive to the acoustic bursts from the transducer; and using the echo signals to determine a distance or time of flight from the transducer.

Abstract: Disclosed sensors, sensor controllers, and sensor control methods enhance transducer performance using a model-based equalization method that can be performed in the field. One illustrative method for operating a piezoelectric-based sensor includes: sensing a response of a piezoelectric transducer as a function of frequency; deriving parameter values of an equivalent circuit for the piezoelectric transducer from the response; using a squared magnitude of the equivalent circuit's transfer function to determine a system level selectivity; and adapting at least one operating parameter of the sensor based on the system level selectivity. One illustrative controller for a piezoelectric transducer includes: a transmitter that drives the piezoelectric transducer; a receiver that senses a response of the piezoelectric transducer; and a processing circuit coupled to the transmitter and to the receiver to calibrate the transducer using the foregoing method.

Abstract: An illustrative controller includes: a transmitter to drive the acoustic transducer to generate a series of acoustic bursts; a receiver coupled to the acoustic transducer to sense a response for each acoustic burst in the series; and a processing circuit to derive output data from said responses in part by determining a difference between one of the responses and at least a portion of another one of the responses. Another illustrative controller includes: a transmitter to drive the acoustic transducer to generate a series of acoustic bursts with signature sequence of frequency displacements; a receiver coupled to the acoustic transducer to sense a response for each acoustic burst in the series; and a processing circuit to derive output data from said responses in part by suppressing any peaks not conforming to the signature sequence.

Abstract: Various sensors, sensor controllers, and sensing methods are suitable for use in a multi-channel ultrasonic sensor array such as those used in systems for parking assistance, blind spot monitoring, and driver assistance. One illustrative acoustic sensing method includes: driving an acoustic transducer to send acoustic bursts each including an up-chirp in a first frequency band and a down-chirp in a second frequency band; receiving echo signals responsive to the acoustic bursts from the transducer; and using the echo signals to determine a distance or time of flight from the transducer. Another acoustic sensing method includes: driving an acoustic transducer to send acoustic bursts each including a concurrent up-chirp and down-chirp; receiving echo signals responsive to the acoustic bursts from the transducer; and using the echo signals to determine a distance or time of flight from the transducer.