Abstract: A method for providing digital communication over an acoustic channel is disclosed. The method includes dividing an operating frequency band of the acoustic channel into multiple adjacent non-overlapping subbands of an equal bandwidth, selecting subbands based on a symbol to be transmitted, generating a signal with linear frequency modulation in each of the selected subbands, combining the signals with linear frequency modulation, and transmitting the combined signals to the acoustic channel through an acoustic system, wherein slopes of linear frequency modulation for the signals with linear frequency modulation are equal.

Abstract: A system for providing a second screen experience to an end user is disclosed. The system may include a first media device including one or more processors configured to receive a broadcast signal encoded with steganographic metadata, extract a payload from the steganographic metadata, and transmit a steganographic metadata signal, the steganographic metadata signal including the extracted payload. The system may further include a second media device including one or more processors configured to receive the steganographic metadata signal from the first media device, determine one or more data identifiers within the received steganographic metadata signal, and execute one or more actions based on the one or more data identifiers.

Abstract: A method for coordinating multiple mobile devices includes generating, with one or more processors of a controller, an inaudible audio signal including one or more audio triggering patterns. The method also includes outputting, with a speaker unit, the inaudible audio signal including one or more audio triggering patterns to one or more mobile devices, wherein the one or more triggering patterns correspond with one or more actions executable by the one or more mobile devices.