Wireless headset having improved RF immunity to RF electromagnetic interference produced from a mobile wireless communications device

• US 7,515,944 B2
• Filed: 11/30/2005
• Issued: 04/07/2009
• Est. Priority Date: 11/30/2005
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Research In Motion Limited (Blackberry Limited)
• Inventors: Mankaruse, George, Zhu, Lizhong, Corrigan, Michael
• Primary Examiner(s): Anderson; Matthew D
• Assistant Examiner(s): HUANG, WEN WU
• Application Number:
  US11/289,904
• Publication Number:
  US 20070123323A1
• Time in Patent Office: 1,224 Days
• Field of Search: 455/41, 455/569.1, 455/570, 455/575.1, 455/296, 455/300, 455/301, 439/76.1, 439/78, 439/83
• US Class Current: 455/569.1
• CPC Class Codes: H04M 1/05 specially adapted for use on head, throat or breast
• CPC Class Codes: H04M 1/6025 implemented as integrated speech networks
• CPC Class Codes: H04M 2250/02 including a Bluetooth interface

Abstract

A wireless headset has improved immunity to RF electromagnetic interference produced from wireless communications devices. A headset body is adapted to be worn by a user and includes a microphone and earpiece. An antenna receives wireless communication signals and passes them to RF and audio circuitry mounted within the headset body. The RF and audio circuitry include a Bluetooth module operatively connected to the antenna for transmitting and receiving wireless communication signals, an audio CODEC connected to the Bluetooth module, and audio connection lines connected between the CODEC and the earpiece and between the CODEC and the microphone. A filter is connected into each of the audio connection lines at the earpiece and microphone and operative for reducing the RF coupling from a mobile wireless communications device.

Claims

1. A wireless headset having improved immunity to RF electromagnetic interference produced from wireless communications devices comprising:

a headset body adapted to be worn by a user;

a microphone carried by the headset body for receiving voice signals from the user;

an earpiece carried by the headset body for directing voice signals into an ear canal of the user;

an antenna carried by the headset body for receiving wireless communications signals;

RF and audio circuitry mounted within the headset body for receiving and transmitting wireless communications signals, said RF and audio circuitry comprising a Bluetooth module operatively connected to said antenna for transmitting and receiving wireless communications signals, an audio CODEC connected to said Bluetooth module, and further comprising a circuit board mounted within the headset body and audio connection lines formed as circuit traces on the circuit board and connected between said CODEC and said earpiece and connected between said CODEC and said microphone; and

a filter connected into each of the audio connection lines at the earpiece and microphone and operative for reducing the RF coupling from a wireless communications device wherein each signal trace includes a respective filter serially connected into each signal trace and a ferrite bead formed on a circuit trace and having a length as an overcoat on the circuit trace sufficient for enabling RF suppression.

2. A wireless headset according to claim 1, wherein a filter comprises an LC filter serially connected into an audio connection line.

3. A wireless headset according to claim 1, and further comprising a series connected inductor and capacitor connected into an audio connection line that is connected to said earpiece.

4. A wireless headset according to claim 3, wherein said inductor comprises a ferrite inductor.

5. A wireless headset according to claim 1, and further comprising an RF shield surrounding one of at least the earpiece or microphone to aid in reducing the RF coupling from a wireless communications device.

6. A wireless headset according to claim 5, wherein said RF shield comprises a metallic housing.

7. A wireless headset according to claim 1, wherein said headset body includes a pivoting microphone arm that supports the microphone.

8. A wireless headset according to claim 1, and further comprising an earmount pivotally connected to said headset body.

9. A wireless headset having improved immunity to RF electromagnetic interference produced from wireless communications devices comprising:

a headset body adapted to be worn by a user;

a microphone carried by the headset body for receiving voice signals from the user;

an earpiece carried by the headset body for directing voice signals into an ear canal of the user;

an antenna carried by the headset body for receiving wireless communications signals;

RF and audio circuitry mounted within the headset body for receiving and transmitting wireless communications signals, said RF and audio circuitry comprising a Bluetooth module operatively connected to said antenna for transmitting and receiving wireless communications signals, an audio CODEC connected to said Bluetooth module, and further comprising a circuit board mounted within the headset body and audio connection lines formed as circuit traces on the circuit board and connected between said CODEC and said earpiece and between said CODEC and said microphone, and microphone bias lines formed as circuit traces on the circuit board and connecting the CODEC and microphone for passing microphone bias control signals between the CODEC and the microphone;

a filter connected into each of the audio connection lines connecting the earpiece and microphone and operative for reducing the RF coupling from a mobile wireless communications device; and

a microphone bias filter connected into each of the microphone bias lines for reducing the RF coupling from a wireless communications device wherein each signal trace for both the audio connection lines and microphone bias lines includes a respective filter serially connected into each signal trace and comprises a ferrite bead formed on a circuit trace and having a length as an overcoat on the circuit trace sufficient for enabling RF suppression.

10. A wireless headset according to claim 9, wherein said microphone bias filter comprises a serial inductor or shunt capacitor.

11. A wireless headset according to claim 9, wherein said microphone bias filter comprises a ground connected capacitor.

12. A wireless headset according to claim 9, wherein a filter comprises an LC filter serially connected into an audio connection line.

13. A method of making a wireless headset having improved immunity to RF electromagnetic interference produced from wireless communications devices, which comprises:

providing a headset body adapted to be worn by a user, a microphone carried by the headset body for receiving voice signals from the user, an earpiece carried by the headset body for directing voice signals into an ear canal of the user, an antenna carried by the headset body for receiving wireless communications signals, RF and audio circuitry mounted within the headset body for receiving and transmitting wireless communications signals, said RF and audio circuitry comprising a Bluetooth module operatively connected to said antenna for transmitting and receiving wireless communications signals and an audio CODEC connected to said Bluetooth module and further comprising a circuit board mounted within the headset body; and

reducing the RF coupling from a wireless communications device by connecting a filter into audio connection lines formed as signal traces on the circuit board that connect the earpiece and microphone with the CODEC such that each signal trace includes a respective filter serially connected into each signal trace and comprising a ferrite bead formed as a circuit trace and having a length as an overcoat on the circuit trace sufficient for enabling RF suppression.

14. A method according to claim 13, which further comprises enclosing one of at least the microphone or earpiece within an RF shield for reducing the RF coupling from a mobile wireless communications device.

15. A method according to claim 13, which further comprises connecting a microphone bias filter into microphone bias lines that pass microphone bias control signals between the CODEC and the microphone.