Patent ID: 8750473

Claim:
A peer-to-peer method of acoustically and bi-directionally communicating information between a first portable device and a second, the method comprising: encoding first information in a signal that, when converted into first acoustic energy at an acoustic transducer of the first portable device, is characterized in that the first acoustic energy is discernable to a human ear yet the encoding of the first information therein is not perceivable by the human apart from the first acoustic energy itself; transmitting the first acoustic energy from the acoustic transducer of the first portable device toward the second portable device across an air gap that constitutes a substantially entirety of the distance therebetween; and receiving at the acoustic transducer of the first portable device second acoustic energy, the second acoustic energy being from the second portable device, wherein the second acoustic energy is also characterized in that the second acoustic energy is itself discernable to a human ear yet an encoding of second information therein is not perceivable by the human.