Low-latency communication protocol for binaural applications
Hearing instruments, such as hearing aids, may improve a quality of presented audio through the use of a binaural application, such as beamforming. The binaural application may require communication between the hearing instruments so that audio from a left hearing instrument may be combined with audio from a right hearing instrument. The combining at a hearing instrument can require synchronizing audio sampled locally with sampled audio received from wireless communication. This synchronization may cause a noticeable delay of an output of the binaural application if the latency of the wireless communication is not low (e.g., a few samples of delay). Presented herein is a low-latency communication protocol that communicates packets on a sample-by-sample basis and that compensates for delays caused by overhead protocol data transmitted with the audio data.
1. A hearing instrument system, comprising:
a first hearing instrument designated as master and configured to be worn at a first ear of a user, the first hearing instrument including:
a first microphone;
a first speaker;
a first transceiver configured for wireless communication; and
a first processor configured to execute software instructions stored in a first memory, the software instructions, when executed, causing the first processor to:
transmit a first channel of audio samples collected at the first microphone in packets that contain audio samples, the packets being transmitted as the audio samples are collected so that a latency in the wireless communication is within one order of magnitude of a sample period of the audio samples; and
a second hearing instrument designated as slave and configured to be worn at a second ear of the user, the second hearing instrument including:
a second microphone;
a second speaker;
a second transceiver configured for wireless communication; and
a second processor configured to execute software instructions stored in a second memory, the software instructions causing the second processor to:
transmit a second channel of audio samples collected at the second microphone in packets that contain audio samples, the packets being transmitted as the audio samples are collected;
receive the first channel of audio samples collected at the first microphone;
combine the first channel and the second channel for a binaural application; and
couple an output of the binaural application to the second speaker.
2. The hearing instrument system according to claim 1 , wherein each packet contains one audio sample.
3. The hearing instrument system according to claim 1 , wherein the one order of magnitude of the sample period is microseconds.
4. The hearing instrument system according to claim 1 , wherein the wireless communication includes near field magnetic induction (NFMI).
5. The hearing instrument system according to claim 1 , wherein the binaural application is beamforming.
6. The hearing instrument system according to claim 1 , wherein the combining includes synchronizing the first channel and the second channel.
7. The hearing instrument system according to claim 1 , wherein the packets include protocol packets and data packets.
8. The hearing instrument system according to claim 7 , wherein the protocol packets and the data packets are transmitted in a frame, the protocol packets being separated by a plurality of data packets.
9. A hearing instrument system, comprising:
a first hearing instrument designated as master and configured to be worn at a first ear of a user, the first hearing instrument including:
a first microphone;
a first speaker;
a first transceiver configured for wireless communication; and
a first processor configured to execute software instructions stored in a first memory, the software instructions, when executed, causing the first processor to:
transmit a first channel of audio samples collected at the first microphone in a first stream of protocol packets spaced apart by a plurality of data packets that contain audio samples and that are transmitted as the audio samples are collected, each of the plurality of data packets being shorter than each of the protocol packets so that a latency added by the stream of protocol packets to the transmitted audio samples is reduced; and
a second hearing instrument designated as slave and configured to be worn at a second ear of the user, the second hearing instrument including:
a second microphone;
a second speaker;
a second transceiver configured for wireless communication; and
a second processor configured to execute software instructions stored in a second memory, the software instructions causing the second processor to:
transmit a second channel of audio samples collected at the second microphone in packets that contain audio samples, the packets being transmitted as the audio samples are collected; and
receive the first channel of audio samples collected at the first microphone.
10. The hearing instrument system according to claim 9 , wherein the first hearing instrument is a first hearing aid and the second hearing instrument is a second hearing aid.
11. The hearing instrument system according to claim 9 , wherein each data packet includes one audio sample.
12. The hearing instrument system according to claim 9 wherein the wireless communication includes near field magnetic induction (NFMI).
13. The hearing instrument system according to claim 9 , wherein the second processor is further configured to:
combine the first channel and the second channel for a binaural application.
14. The hearing instrument system according to claim 13 , wherein the binaural application is beamforming.
15. The hearing instrument system according to claim 9 , wherein the latency is within an order of magnitude of a sample period of the first channel of audio samples.
16. A method for communication between a first hearing instrument and a second hearing instrument, the method comprising:
designating the first hearing instrument as a master and the second hearing instrument as a slave;
collecting audio samples from a first microphone of the first hearing instrument;
transmitting a first channel of the audio samples in packets from the first hearing instrument to the second hearing instrument, the packets being transmitted as the audio samples are collected so that a latency in the communication is within one order of magnitude of a sample period of the audio samples;
receiving the first channel of audio samples at the second hearing instrument;
collecting audio samples from a second microphone of the second hearing instrument for a second channel; and
combining the first channel and the second channel for a binaural application.
17. The method according to claim 16 , further comprising:
coupling an output of the binaural application to a second speaker of the second hearing instrument.
18. The method according to claim 16 , further comprising:
transmitting the second channel of the audio samples in packets from the second hearing instrument to the first hearing instrument, the packets being transmitted as the audio samples are collected so that a latency in the communication is within one order of magnitude of a sample period of the audio samples of the second channel.
19. The method according to claim 16 , wherein each packet contains one audio sample.
20. The method according to claim 16 , wherein the communication includes near field magnetic induction (NFMI).