Data delivery using acoustic transmissions

1. An apparatus comprising a transmitter configured to:

receive a first signal to be transmitted to a device within an area covered by an audio system configured to emit acoustic signals into the area;

map the first signal to a set of symbols to generate a sequence of symbols corresponding to the first signal;

add a pilot sequence to the sequence of symbols;

modulate a carrier frequency using the sequence of symbols to generate a second signal in an acoustic band that carries the first signal; and

transmit the second signal to the audio system.

2. The apparatus of claim 1 wherein the transmitter is further configured to:

apply a filter to the first signal to limit an effective bandwidth of the second signal.

3. The apparatus of claim 1 further comprising the device, wherein the device is configured to:

receive an acoustic signal from the audio system that includes the second signal;

extract the sequence of symbols from the second signal; and

use the pilot sequence for one or more of synchronization, determining a frequency mismatch, determining a phase mismatch, or to characterize a channel.

4. The apparatus of claim 1 wherein the acoustic band consists of frequencies beyond an audible range of human hearing, but within a range of frequencies that can be transmitted by the audio system.

5. The apparatus of claim 1 further comprising the device, wherein the device is configured to:

receive an acoustic signal from the audio system that includes the second signal;

extract the first signal from the second signal; and

provide the first signal to a user of the device.

6. The apparatus of claim 5 wherein extracting the first signal from the second signal includes detecting a frame of the first signal, and the device is further configured to activate audio circuitry in response to detecting the frame.

7. The apparatus of claim 1 wherein the area is a space proximate to a vehicle, and the first signal is received from a data source associated with the vehicle.

8. The apparatus of claim 7 wherein the device is configured to display information related to a condition of the vehicle based on the first signal.

9. The apparatus of claim 1 further comprising the device, wherein the device is coupled to a controller and configured to provide the first signal to the controller.

10. The apparatus of claim 1 wherein the first signal includes metadata related to an audio signal being transmitted by the audio system, and the device is configured to display the metadata.

11. The apparatus of claim 1 wherein the first signal includes a plurality of frames, the pilot sequence includes a plurality of pilot symbols, and the transmitter is configured to:

add the pilot sequence to the sequence of symbols by inserting a pilot symbol into each frame of the first signal to form data packets.

12. The apparatus of claim 11 wherein the pilot symbol is inserted as a header of the frame.

13. The apparatus of claim 11 wherein the transmitter is configured to map the first signal to the set of symbols to generate the sequence of symbols corresponding to the first signal by mapping each data packet to one or more symbols of the sequence of symbols.

14. A method comprising:

receiving a first signal to be transmitted to a device within an area covered by an audio system configured to emit acoustic signals into the area;

mapping the first signal to a set of symbols to generate a sequence of symbols corresponding to the first signal;

adding a pilot sequence to the sequence of symbols;

modulating a carrier frequency using the sequence of symbols to generate a second signal in an acoustic band that carries the first signal; and

transmitting the second signal to the audio system.

15. The method of claim 14 wherein the acoustic band consists of frequencies beyond an audible range of human hearing, but within a range of frequencies that can be transmitted by the audio system.

16. The method of claim 14 further comprising:

receiving an acoustic signal from the audio system that includes the second signal at a user device;

extracting the first signal from the second signal; and

providing the first signal to a user of the user device.

17. The method of claim 16 wherein extracting the first signal from the second signal includes detecting a frame of the first signal, and the user device is further configured to activate audio circuitry in response to detecting the frame.

18. The method of claim 14 wherein the area is a space proximate to a vehicle and the first signal is received from a data source associated with the vehicle, and further comprising displaying information related to a condition of the vehicle based on the first signal.

19. The method of claim 14 further comprising:

receiving an acoustic signal from the audio system that includes the second signal at a receiver;

extracting the first signal from the second signal; and

transmitting the first signal to a controller.

20. The method of claim 14 wherein the first signal includes metadata related to an audio signal being transmitted by the audio system, and further comprising displaying the metadata on the device.

21. A computer program product comprising:

a non-transitory computer-readable storage medium; and

program code stored on the non-transitory computer-readable storage medium that, when executed by one or more processors, causes the one or more processors to:

receive a first signal to be transmitted to a device within an area covered by an audio system configured to emit acoustic signals into the area;

map the first signal to a set of symbols to generate a sequence of symbols corresponding to the first signal;

add a pilot sequence to the sequence of symbols;

modulate a carrier frequency using the sequence of symbols to generate a second signal in an acoustic band that carries the first signal; and

transmit the second signal to the audio system.