Transmission of Directional Perception

With conventional earphone listening, accurate simulation of the direction of sound arrival is impossible because the sound field is not fixed in space but rotates with the head. A system for overcoming this limitation has been developed. Signals are transmitted by electromagnetic or underwater radiation to two directional receptors attached to the listener's head. The receptors are connected to the earphones through a Ster-Bin network. This network divides each of the signals from the receptors into two parts. One part is fed into its corresponding earphone; the other is delayed with respect to the first by the time interval required for sound to travel normally between the two ears, and is fed into the opposite earphone. In addition, both parts are modified at high frequencies to simulate the diffraction effects attributable to the head. The varying relative signal strengths from the directional receptors, as a function of the direction of signal arrival, modified by the Ster-Bin network, provide the listener with orientation capability. Further apparatus improvement and applications to aerospace and underwater swimmers' communications devices are envisioned.