Emergency Warning and Bidirectional Communication via Digital Audio Broadcast.

Sending broadcast messages is an efficient means of communicating in emergency situations, especially during serious disasters. This paper focuses on the digital audio broadcast (DAB) system. First, several new techniques are reported to enhance the emergency warning message (EWM) receiving and display functionalities for both personal and public DAB terminals. Then, a novel bidirectional communication method between two DAB transmitters is proposed, to enable the communication to and from the disaster area and the outside. Experiments show that the EWM can be correctly sent to the intended DAB terminals within 0.2–3 s, and the existing public light emitting diode screens can be expanded as DAB EWM terminals without affecting their normal functions. The bidirectional multimedia communication between two DAB transmitters is also successfully demonstrated. The proposed techniques expand upon the DAB’s existing functionality, and can benefit more people during emergencies. [ABSTRACT FROM AUTHOR]