Package waveguide for acoustic sensor with electronic delay compensation
A system and method use an array of ultrasonic transducers to emit and receive sound in a phased array fashion by using acoustic waveguides to achieve a desired acoustic radiation and reception pattern. A chip package attached to an acoustic transducer array includes acoustic waveguides coupled to acoustic ports. Each waveguide is coupled between a corresponding acoustic transducer and a corresponding acoustic port. A spacing of a pair of acoustic ports is different than a spacing of a corresponding pair of acoustic transducers.
1. An acoustic transducer package, comprising:
an acoustic transducer array having a plurality of acoustic transducers formed on a substrate;
a chip package attached to the acoustic transducer array, wherein the chip package includes a plurality of acoustic waveguides coupled to a plurality of acoustic ports, wherein each acoustic waveguide in the plurality of acoustic waveguides is coupled between a corresponding acoustic transducer in the plurality of acoustic transducers and a corresponding acoustic port in the plurality of acoustic ports, wherein a spacing of a pair of acoustic ports in the plurality of acoustic ports is different than a spacing of a corresponding pair of acoustic transducers in the plurality of acoustic transducers.
2. The acoustic transducer package of claim 1 , wherein the spacing of the pair of acoustic ports in the plurality of acoustic ports is larger than the spacing of the corresponding pair of acoustic transducers in the plurality of acoustic transducers.
3. The acoustic transducer package of claim 1 , wherein the spacing of the pair of acoustic ports in the plurality of acoustic ports is smaller than the spacing of the corresponding pair of acoustic transducers in the plurality of acoustic transducers.
4. The acoustic transducer package of claim 1 , wherein the acoustic ports in the plurality of acoustic ports are spaced with a pitch that is less than 5λ, where λ is an acoustic wavelength.
5. The acoustic transducer package of claim 1 , wherein the spacing between acoustic ports in the plurality of acoustic ports is non-uniform.
6. The acoustic transducer package of claim 4 , wherein the pitch is between ½λ and λ.
7. The acoustic transducer package of claim 1 , wherein one or more acoustic waveguides in the plurality of acoustic waveguides are characterized by a length of ¼λ*(2n−1)+C where λ is an acoustic wavelength, n=is a positive integer and C is a correction term that accounts for end effects produced by the acoustic ports.
8. The acoustic transducer package of claim 1 , further comprising an integrated circuit coupled to the acoustic transducer array.
9. The acoustic transducer package of claim 8 , wherein the integrated circuit is attached to the chip package.
10. The acoustic transducer package of claim 8 , wherein the integrated circuit includes a signal generation unit configured to generate a plurality of driving signals, wherein each driving signal of the plurality of driving signals drives a corresponding transducer of the plurality of transducers.
11. The acoustic transducer package of claim 10 , further comprising a plurality of signal amplifiers coupled between the signal generation unit and the acoustic transducer array, wherein each signal amplifier of the plurality of signal amplifiers amplifies a corresponding driving signal of the plurality of driving signals.
12. The acoustic transducer package of claim 10 , further comprising a plurality of delay elements coupled between the signal generation unit and the acoustic transducer array, wherein each delay element of the plurality of delay elements applies a delay to a corresponding driving signal of the plurality of driving signals.
13. The acoustic transducer package of claim 8 , wherein the integrated circuit includes a beamforming and target recognition block coupled to the acoustic transducer array.
14. The acoustic transducer package of claim 13 , wherein the beamforming and target recognition block is configured to extract features signals received from the acoustic transducer array.
15. The acoustic transducer package of claim 13 , wherein the beamforming and target recognition block is configured to perform spatial filtering of signals received from the acoustic transducer array.
16. The acoustic transducer package of claim 13 , further comprising a plurality of signal amplifiers coupled between the beamforming and target recognition block and the acoustic transducer array, wherein each signal amplifier of the plurality of signal amplifiers amplifies a corresponding received signal from a corresponding acoustic transducer of the plurality of acoustic transducers.
17. The acoustic transducer package of claim 13 , further comprising a plurality of delay elements coupled between beamforming and target recognition block and the acoustic transducer array, wherein each delay element of the plurality of delay elements applies a delay to a corresponding received signal from a corresponding acoustic transducer of the plurality of acoustic transducers.
18. A method, comprising:
generating a plurality of acoustic signals with an acoustic transducer array having a plurality of acoustic transducers formed on a substrate;
transmitting each acoustic signal in the plurality of acoustic signals through a corresponding acoustic waveguide of a plurality of acoustic waveguides coupled to a plurality of acoustic ports, wherein each acoustic waveguide in the plurality of acoustic waveguides is coupled between a corresponding acoustic transducer in the plurality of acoustic transducers and a corresponding acoustic port in the plurality of acoustic ports, wherein a spacing of a pair of acoustic ports in the plurality of acoustic ports is different than a spacing of a corresponding pair of acoustic transducers in the plurality of acoustic transducers, wherein one or more acoustic waveguides in the plurality of acoustic waveguides are characterized by a length of ¼λ*(2n−1)+C where λ is an acoustic wavelength, n=is a positive integer and C is a correction term that accounts for end effects produced by the acoustic ports.
19. The method of claim 18 , wherein generating the plurality of acoustic signals includes generating a plurality of driving signals that drive the one or more acoustic transducers, wherein each driving signal of the plurality of driving signals drives a corresponding transducer of the plurality of transducers.
20. The method of claim 19 , further comprising amplifying the plurality of driving signals with a plurality of signal amplifiers coupled between the signal generation unit and the acoustic transducer array, wherein each signal amplifier of the plurality of signal amplifiers amplifies a corresponding driving signal of the plurality of driving signals.
21. The method of claim 19 , further comprising delaying the plurality of driving signals with a plurality of delay elements coupled to the acoustic transducer array, wherein each delay element of the plurality of delay elements applies a delay to a corresponding driving signal of the plurality of driving signals.
22. A method, comprising:
receiving one or more acoustic signals at a plurality of acoustic ports;
transmitting the one or more acoustic signals through a plurality of acoustic waveguides to a plurality of acoustic transducers formed on a substrate, wherein each acoustic waveguide in the plurality of acoustic waveguides is coupled between a corresponding acoustic transducer in the plurality of acoustic transducers and a corresponding acoustic port in the plurality of acoustic ports,
wherein a spacing of a pair of acoustic ports in the plurality of acoustic ports is different than a spacing of a corresponding pair of acoustic transducers in the plurality of acoustic transducers; and
generating a plurality of received signals with the plurality of acoustic transducers from the one or more acoustic signals.
23. The method of claim 22 , further comprising extracting features from the plurality of received signals generated with the acoustic transducer array.
24. The method of claim 22 , further comprising performing spatial filtering on the plurality of received signals generated with the acoustic transducer array.
25. The method of claim 22 , further comprising amplifying the plurality of received signals with a plurality of signal amplifiers coupled to the acoustic transducer array, wherein each signal amplifier of the plurality of signal amplifiers amplifies a corresponding received signal from a corresponding acoustic transducer of the plurality of acoustic transducers.
26. The method of claim 22 , further comprising delaying the plurality of received signals with a plurality of delay elements coupled to the acoustic transducer array, wherein each delay element of the plurality of delay elements applies a delay to a corresponding received signal from a corresponding acoustic transducer of the plurality of acoustic transducers.