Sensor array module for an advanced driver assistance system
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.
1 . A smart ultrasonic integrated-circuit, comprising:
a transmitter coupled to a piezoelectric transducer configured to transmit an ultrasonic-transmit-signal towards an obstacle;
a first receiver configured to receive a first receive-signal from a first MEMS device, the first receive-signal including a first ultrasonic portion and a first audio portion;
a second receiver configured to receive a second receive-signal from a second MEMS device, the second receive-signal including a second ultrasonic portion and a second audio portion; and
a processor configured to:
process the first ultrasonic portion of the first receive-signal and the second ultrasonic portion of the second receive-signal to determine two-dimensional range information for the obstacle;
process the first audio portion of the first receive-signal and the second audio portion of the second receive-signal to determine audio information for a sound source; and
output the two-dimensional range information and the audio information.
2 . The smart ultrasonic integrated-circuit according to claim 1 , wherein the processor is further configured to:
capture a first ultrasonic-echo included in the first receive-signal;
capture a second ultrasonic-echo included in the second receive-signal;
determine a phase shift between the first ultrasonic-echo and the second ultrasonic-echo; and
determine a time-of-flight based on the first ultrasonic-echo or the second ultrasonic-echo.
3 . The smart ultrasonic integrated-circuit according to claim 2 , wherein the processor is further configured to:
output the time-of-flight and the phase shift as the two-dimensional range information.
4 . The smart ultrasonic integrated-circuit according to claim 2 , wherein the processor is further configured to:
determine a range to the obstacle based on the time-of-flight;
determine a height of the obstacle based on the phase shift; and
output the range and the height as the two-dimensional range information.
5 . The smart ultrasonic integrated-circuit according to claim 1 , wherein the processor is further configured to:
capture an audible sound included in the first receive-signal or the second receive-signal.
6 . The smart ultrasonic integrated-circuit according to claim 5 , wherein the processor is further configured to:
output raw audio-data corresponding to the audible sound as the audio information.
7 . The smart ultrasonic integrated-circuit according to claim 5 , wherein the processor is further configured to:
classify the audible sound to determine an identity of the sound source; and
output the identity as the audio information.
8 . The smart ultrasonic integrated-circuit according to claim 1 , wherein:
the first receiver is configured to capture the first ultrasonic portion of the first receive-signal and the first audio portion of the first receive-signal simultaneously; and
the second receiver is configured to capture the second ultrasonic portion of the second receive-signal and the second audio portion of the second receive-signal simultaneously.
9 . A smart ultrasonic integrated-circuit, comprising:
a transmitter coupled to a piezoelectric transducer configured to transmit an ultrasonic-transmit-signal towards an obstacle;
a first receiver configured to receive a first receive-signal from the piezoelectric transducer, the first receive-signal including a first ultrasonic-echo;
a second receiver configured to receive a second receive-signal from a MEMS device, the second receive-signal including a second ultrasonic-echo and an audio signal; and
a processor configured to:
determine a two-dimensional range based on the first ultrasonic-echo and the second ultrasonic-echo;
determine audio information based on the audio signal; and
output the two-dimensional range and the audio information.
10 . The smart ultrasonic integrated-circuit according to claim 9 , wherein the processor is further configured to:
capture a leakage signal included in the second receive-signal, the leakage signal received by the MEMS device while the piezoelectric transducer is in a transmit mode; and
determine an operating characteristic of the piezoelectric transducer based on the leakage signal.
11 . The smart ultrasonic integrated-circuit according to claim 9 , further including:
a temperature sensor; and
a memory that is configured to store a calibration file corresponding to an offset phase-shift between the piezoelectric transducer and the MEMS device.
12 . The smart ultrasonic integrated-circuit according to claim 9 , wherein the processor is further configured to:
determine a range to the obstacle based on a time-of-flight of the first ultrasonic-echo or the second ultrasonic-echo;
determine a height of the obstacle based on a phase shift between the first ultrasonic-echo and the second ultrasonic-echo; and
output the range the height as the two-dimensional range.
13 . The smart ultrasonic integrated-circuit according to claim 9 , wherein the processor further includes a classifier configured to:
recognize the audio signal; and
output an identity of a sound source of the audio signal as the audio information.
14 . The smart ultrasonic integrated-circuit according to claim 9 , wherein the processor is further configured to:
output a stream of audio samples corresponding to the audio signal as the audio information.
15 . The smart ultrasonic integrated-circuit according to claim 9 , wherein the second receiver includes an analog-to-digital converter configured to capture the second ultrasonic-echo and the audio signal simultaneously from the second receive-signal.
16 . The smart ultrasonic integrated-circuit according to claim 9 , wherein the smart ultrasonic integrated-circuit is disposed in an electronic package, the MEMS device is wire bonded to the smart ultrasonic integrated-circuit within the electronic package.
17 . A non-transitory computer-readable medium storing instructions that, when executed by a processor of a smart ultrasonic integrated-circuit, cause the smart ultrasonic integrated-circuit to:
transmit, via a transmitter coupled to a piezoelectric transducer, an ultrasonic-transmit-signal towards an obstacle;
receive, via a first receiver, a first receive-signal from a first MEMS device, the first receive-signal including a first ultrasonic portion and a first audio portion;
receive, via a second receiver, a second receive-signal from a second MEMS device, the second receive-signal including a second ultrasonic portion and a second audio portion;
process the first ultrasonic portion of the first receive-signal and the second ultrasonic portion of the second receive-signal to determine two-dimensional range information for the obstacle;
process the first audio portion of the first receive-signal and the second audio portion of the second receive-signal to determine audio information for a sound source; and
output the two-dimensional range information and the audio information.
18 . The non-transitory computer-readable medium according to claim 17 , wherein the instructions further cause the smart ultrasonic integrated-circuit to:
capture a first ultrasonic-echo included in the first receive-signal;
captured a second ultrasonic-echo included in the second receive-signal;
determine a phase shift between the first ultrasonic-echo and the second ultrasonic-echo;
determine a time-of-flight based on the first ultrasonic-echo of the second ultrasonic-echo; and
output the time-of-flight and the phase shift as the two-dimensional range information.
19 . The non-transitory computer-readable medium according to claim 17 , wherein the instructions further cause the smart ultrasonic integrated-circuit to:
capture a first ultrasonic-echo included in the first receive-signal;
capture a second ultrasonic-echo included in the second receive-signal;
determine a phase shift between the first ultrasonic-echo and the second ultrasonic-echo;
determine a time-of-flight based on the first ultrasonic-echo or the second ultrasonic-echo;
determine a range to the obstacle based on the time-of-flight;
determine a height of the obstacle based on the phase shift; and
output the range and the height as the two-dimensional range information.
20 . The non-transitory computer-readable medium according to claim 17 , wherein the instructions further cause the smart ultrasonic integrated-circuit to:
capture an audible sound included in the first receive-signal or the second receive-signal; and
output raw audio-data corresponding to the audible sound as the audio information.
21 . The non-transitory computer-readable medium according to claim 17 , wherein the instructions further cause the smart ultrasonic integrated-circuit to:
capture an audible sound included in the first receive-signal or the second receive-signal;
classify the audible sound to determine an identity of the sound source; and
output the identity as the audio information.