Digital audio radio-an application of audio compression technology

Signal compression is a key element in emerging technology for digital audio. AT&T Bell Laboratories algorithms for perceptual audio coding have provided the capability of compressing compact disc (CD) stereo audio at 1406 kbits/sec into rates approximating 128 kbits/sec. This capability has enabled the development of new applications in digital audio transmission and broadcasting. In the past few years, Digital Audio Broadcasting-having transmission formats ranging from terrestrial to cable, to satellite-has proven to be a powerful and timely technology through various tests. Many people view that Digital Audio Broadcasting is the logical progression in sound transmission for the next century. Digital Audio Broadcasting´s fundamental promises include CD-quality sound and superior immunity to interference. A Digital Audio Broadcasting system also offers the potential of many new broadcast services, including both information transfer and messaging which can easily be implemented into digital technology. We describe an in-band adjacent channel (IBAC) Digital Audio Broadcasting system which was developed at AT&T Bell Laboratories, an ongoing process for creating a Digital Audio Broadcasting standard in the United States, and some preliminary laboratory test results of the AT&T IBAC system