Electronic apparatus having microphones with controllable front-side gain and rear-side gain

• US 8,300,845 B2
• Filed: 06/23/2010
• Issued: 10/30/2012
• Est. Priority Date: 06/23/2010
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Inventors: Zurek, Robert, Bastyr, Kevin, Clark, Joel, Ivanov, Plamen
• Primary Examiner(s): Chin, Vivian
• Assistant Examiner(s): SUTHERS, DOUGLAS JOHN
• Application Number:
  US12/822,081
• Publication Number:
  US 20110317041A1
• Time in Patent Office: 860 Days
• Field of Search: 381/92, 381/333, 381/334, 381/306, 381/207, 381/111, 381/122
• US Class Current: 381/92
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers
• CPC Class Codes: H04R 2430/01 Aspects of volume control, not necessarily automatic, in sound systems
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's

Abstract

An electronic apparatus is provided that has a rear-side and a front-side, a first microphone that generates a first signal, and a second microphone that generates a second signal. An automated balance controller generates a balancing signal based on an imaging signal. A processor processes the first and second signals to generate at least one beamformed audio signal, where an audio level difference between a front-side gain and a rear-side gain of the beamformed audio signal is controlled during processing based on the balancing signal.

Claims

1. An electronic apparatus having a rear-side and a front-side, the electronic apparatus comprising:

a first microphone that generates a first signal;

a second microphone that generates a second signal;

a third microphone that generates a third signal;

an automated balance controller that generates a balancing signal based on an imaging signal; and

a processor, coupled to the first microphone, the second microphone, the third microphone, and the automated balance controller, that processes the first signal, the second signal, and the third signal to generate;

a left-front-side beamformed audio signal having a first major lobe with a left-front-side gain,

a right-front-side beamformed audio signal having a second major lobe with a right-front-side gain, and

a third beamformed audio signal having a third rear-side gain,

wherein an audio level difference between the third rear-side gain and both the right-front-side gain and the left-front-side gain is controlled based on the balancing signal.

2. The electronic apparatus of claim 1, further comprising:

a video camera positioned on the front-side and coupled to the automated balance controller.

3. The electronic apparatus of claim 2, wherein the automated balance controller comprises:

a video controller coupled to the video camera.

4. The electronic apparatus of claim 3, wherein the imaging signal is based on an angular field of view of a video frame of the video camera.

5. The electronic apparatus of claim 3, wherein the imaging signal is based on a focal distance for the video camera.

6. The electronic apparatus of claim 3, wherein the imaging signal is a zoom control signal for the video camera that is controlled by a user interface.

7. The electronic apparatus of claim 6, wherein the zoom control signal for the video camera is a digital-zoom control signal.

8. The electronic apparatus of claim 6, wherein the zoom control signal for the video camera is an optical-zoom control signal.

9. The electronic apparatus of claim 1, further comprising:

a front-side proximity sensor that generates a front-side proximity sensor signal that corresponds to a first distance between a video subject and the electronic apparatus, wherein the imaging signal is based on the front-side proximity sensor signal.

10. The electronic apparatus of claim 1, further comprising:

a rear-side proximity sensor that generates a rear-side proximity sensor signal that corresponds to a second distance between a camera operator and the electronic apparatus, wherein the imaging signal is based on the rear-side proximity sensor signal.

11. The electronic apparatus of claim 1, further comprising:

a front-side proximity sensor that generates a front-side proximity sensor signal that corresponds to a first distance between a video subject and the electronic apparatus; and

a rear-side proximity sensor that generates a rear-side proximity sensor signal that corresponds to a second distance between a camera operator and the electronic apparatus,

wherein the imaging signal is based on the front-side proximity sensor signal and the rear-side proximity sensor signal.

12. The electronic apparatus of claim 1, wherein the automated balance controller generates a balancing select signal, wherein at least one of the front-side gain and the rear-side gain of the at least one beamformed audio signal is set to a pre-determined value based on the balancing select signal.

13. The electronic apparatus of claim 1, wherein the first microphone or the second microphone is an omnidirectional microphone.

14. The electronic apparatus of claim 1, wherein the first microphone or the second microphone is a directional microphone.

15. The electronic apparatus according to claim 1,

wherein the right-front-side beamformed audio signal also has a first minor lobe having a first minor lobe rear-side gain, wherein an audio level difference between the right-front-side gain of the second lobe and the first minor lobe rear-side gain is controlled based on the balancing signal,

wherein the left-front-side beamformed audio signal also has a second minor lobe having an other rear-side gain, wherein an audio level difference between the left-front-side gain of the first major lobe and the other rear-side gain of the second minor lobe is controlled based on the balancing signal, and

wherein the first minor lobe and the second minor lobe form the third beamformed audio signal.

16. The electronic apparatus according to claim 1, further comprising:

an Automatic Gain Control (AGC) module, coupled to the processor, that receives the at least one beamformed audio signal, and generates an AGC feedback signal based on the at least one beamformed audio signal, wherein the AGC feedback signal is used to adjust the balancing signal.

17. The electronic apparatus according to claim 1, wherein the processor comprises:

a look up table.

18. A method for processing a first microphone signal, second microphone signal, and a third microphone signal comprising:

generating a balancing signal based on an imaging signal; and

processing the first microphone signal, the second microphone signal, and the third microphone signal to generate;

a left-front-side beamformed audio signal having a first major lobe with a left-front-side gain,

a right-front-side beamformed audio signal having a second major lobe with a right-front-side gain, and

a third beamformed audio signal with a third rear-side gain,

wherein an audio level difference the third rear-side gain and both the right-front-side gain and the left-front-side gain is controlled based on the balancing signal.