Interference cancellation for throat microphone
A throat microphone may include one or more transducers that are in contact with the skin in the region of the larynx of person, and may provide a vibration signal to a processing unit. The vibration signal may also include energy and information relating to secondary physiological phenomena such as breathing and heartbeat, in addition to the desired sonic signal. The processing unit may utilize information relating to the secondary physiological phenomena to control a filter that outputs the desired sonic signal.
1. A system for providing a desired physiological signal based on vibrations of a throat area of a person, comprising:
a vibration sensor;
a processor coupled to the vibration sensor, wherein the processor is configured to receive a vibration signal from the vibration sensor, identify a characteristic of the vibration signal that is associated with a secondary physiological phenomena, determine a filter control parameter based on the characteristic, and provide the desired physiological signal based on the filter control parameter and the vibration signal; and
a communication unit coupled to the processor and in communication with a device, wherein the communication unit transmits the desired physiological signal to the device.
2. The system of claim 1 , wherein the characteristic is a cutoff frequency and the vibration signal is filtered with a high-pass filter based on the filter control parameter.
3. The system of claim 2 , wherein the processor is configured to calculate a filter shift value based on the cutoff frequency and a sampling rate of the filter, and provide the filter shift value as the filter control parameter.
4. The system of claim 1 , wherein the secondary physiological phenomena comprises at least one of respiration or heartbeat.
5. The system of claim 1 , wherein the desired physiological signal comprises a sonic signal.
6. The system of claim 1 , wherein the processor is configured to provide the vibration signal to a plurality of band-pass filters, determine an energy associated with an output of each of the plurality of band-pass filters, and identify the characteristic based on one or more of the determined energies.
7. The system of claim 6 , wherein the processor is configured to provide a signal representative of the secondary physiological phenomena based on the one or more determined energies.
8. The system of claim 1 , wherein the communication unit is a wireless transmitter.
9. The system of claim 8 , wherein processor is configured to encode the desired physiological signal for transmission by the wireless transmitter.