Bone conduction communication system and method of operation

1. A method comprising:

establishing a communicable link between a plurality of bone conduction communication systems each comprising a bone conduction transducer, each bone conduction communication system of the plurality of bone conduction communication systems associated with a distinct user;

operating each of the bone conduction transducers in an input mode wherein the bone conduction transducers are configured to detect a vibration associated with a bone of the respective user;

at a first bone conduction communication system of the plurality of bone conduction communication systems associated with a first user:

detecting a vibration associated with a bone of the first user;

converting the vibration to an audio signal; and

transmitting the audio signal to the remaining bone conduction communication systems of the plurality of bone conduction communication systems;

at a remainder of the bone conduction communication systems, excluding the first bone conduction communication system:

receiving the audio signal;

when the audio signal exceeds a threshold that depends on the first user, switching the bone conduction transducer associated with the respective bone conduction communication system to an output mode, wherein in the output mode the bone conduction transducer outputs the audio signal; and

returning the bone conduction transducer to the input mode a predetermined time after the audio signal stops exceeding the threshold.

2. The method of claim 1 , wherein the threshold depends on a signal strength of the audio signal.

3. The method of claim 1 , wherein the threshold further depends on an environmental noise proximal the first user.

4. The method of claim 1 , wherein the predetermined time is at least 1 ms.

5. The method of claim 4 , wherein the predetermined time is at least 100 ms.

6. The method of claim 5 , wherein the predetermined time is at least 1 s.

7. The method of claim 1 , further comprising, at each of the bone conduction communication systems except the first bone conduction communication system:

comparing the audio signal to a second threshold, the second threshold depending on a user setting of the respective bone conduction communication system;

when the audio signal exceeds the second threshold, attenuating the audio signal; and

when the audio signal is below the second threshold, amplifying the audio signal.

8. The method of claim 7 , wherein the second threshold for the remainder of the bone conduction communication systems further depends on an environmental noise proximal each respective bone conduction communication system of the remainder.

9. The method of claim 1 , wherein at the first bone conduction communication system, transmitting the audio signal comprises transmitting the audio signal when the audio signal exceeds a transmission threshold.

10. The method of claim 1 , further comprising:

detecting an echo in the transmitted signal by detecting an amplification of a frequency in the signal; and

attenuating said frequency of the signal.

11. The method of claim 10 , wherein the frequency is less than about 400 Hertz (Hz) or greater than about 8000 Hz.

12. A bone conduction communication system operable to communicate with a plurality of communication systems, the bone conduction communication system comprising:

a communication module operable to transmit and receive acoustic signals between the plurality of communication systems in the communication channel;

a bone conduction transducer communicably coupled to the communication module, the bone conduction transducer configured to be worn on a head surface of a user and operable between a set of operation modes, comprising:

an output mode wherein the bone conduction transducer transmits a received acoustic signal as a vibration to the head surface of the user; and

an input mode, wherein the bone conduction transducer converts a vibration of the head surface of the user into an acoustic signal; and

a mode selector configured to control the operation mode of the bone conduction transducer, wherein the mode selector is configured to:

operate the bone conduction transducer in the input mode by default;

switch the bone conduction transducer to the output mode when the received acoustic signal associated with a communication systems of the plurality of communication systems exceeds a threshold, wherein the threshold depends on the user associated with the communication system; and

return the bone conduction transducer to input mode a predetermined time after the received acoustic signal no longer exceeds the threshold.

13. The bone conduction communication system of claim 12 , wherein the predetermined time is at least about 100 ms.

14. The bone conduction communication system of claim 12 , wherein the mode selector comprises a digital signal processor and wherein the threshold comprises a digital signal threshold.

15. The bone conduction communication system of claim 12 , wherein the mode selector comprises a threshold relay operable to compare the received acoustic signal to the threshold.

16. The bone conduction communication system of claim 12 , wherein the threshold comprises a threshold voltage associated with the received acoustic signal.

17. The bone conduction communication system of claim 12 , wherein the threshold comprises a dynamic threshold that depends on an ambient sound level proximal a user associated with the received acoustic signal.

18. The bone conduction communication system of claim 12 , further comprising a signal modifier operable to:

attenuate the received acoustic signal when the received acoustic signal exceeds a second threshold; and

amplify the received acoustic signal when the received acoustic signal is less than the second threshold.

19. The bone conduction communication system of claim 18 , wherein the second threshold depends on an ambient sound level proximal the user.

20. The bone conduction communication system of claim 12 , further comprising a bandpass filter configured to transmit signals with frequencies between about 400 and 8000 Hertz (Hz) from the received acoustic signals before outputting the received acoustic signals with the bone conduction transducer.