Microphone system for a communication device

• US 20050069164A1
• Filed: 09/30/2003
• Published: 03/31/2005
• Est. Priority Date: 09/30/2003
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Muthuswamy, Sivakumar, Yeager, David
• Granted Patent: US 7,233,679 B2
• Time in Patent Office: Days
• US Class Current: 381/369
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence

Abstract

A microphone system (100) includes a MEMS microphone (102) and at least one audio port (110) accessing the rear volume portion (106) of the MEMS microphone providing directional functionality, preferably through a MEMS switch (112).

Claims

1. A microphone system, comprising:

a MEMS microphone having a front volume portion and a rear volume portion;

a first audio port accessing the front volume portion;

a second audio port accessing the rear volume portion of the microphone; and

a switch for sealing and unsealing the second audio port.

2. The microphone system of claim 1, wherein the switch is a MEMS switch.

3. The microphone system of claim 1, wherein the switch is a mechanical switch.

4. The microphone system of claim 1, wherein the switch automatically switches the microphone between directional functionality and omni-directional functionality.

5. The microphone system of claim 1, further comprising a third audio port accessing the rear volume portion of the microphone, the second and third audio ports being of different lengths.

6. The microphone system of claim 5, wherein at least one of the second and third audio ports has an acoustic flow resistive material coupled thereto.

7. The microphone system of claim 5, wherein the second and third audio ports have different acoustic flow resistive materials coupled thereto.

8. The microphone system of claim 1, further comprising an acoustic flow resistive material coupled to the second audio port.

9. The microphone system of claim 8, wherein the acoustic flow resistive material is coupled to the second audio port such that when the port is unsealed, acoustic waves are delayed by a predetermined amount of time based on flow resistivity characteristics of the resistive material and a path length of the second audio port.

10. A microphone system, comprising:

a MEMS microphone; and

at least one audio port coupled to the MEMS microphone providing directional functionality.

11. A communication device, including:

a microphone system having a MEMS microphone, the MEMS microphone having a selectable directional port incorporated therein.

12. The communication device of claim 11, wherein the selectable directional port is automatically enabled during speakerphone operation of the communication device

13. The communication device of claim 11, further including:

a controller for automatically enabling the selectable directional port based on the communication device being in a speakerphone mode; and

the controller automatically disabling the selectable directional port based on the communication device being in a close-talking mode.

14. The communication device of claim 11, wherein the selectable directional port is user selectable.

15. The communication device of claim 11, wherein the selectable directional port comprises a user selectable directional port for use in a handsfree speakerphone mode.