The Advanced Audio Systems Group conducts research and development in advanced audio technologies related to digital radio broadcasting (DRB), sound systems accompanying advanced television (ATV) or high definition television (HDTV), as well as to the Internet.

The Group carries out research in four main areas:

• audio source coding techniques for mono, stereo and multichannel sound systems
• psychoacoustics
• subjective evaluation of audio and speech systems
• channel coding and modulation techniques suitable for one way transmission of digital information (data, audio, etc.) to fixed, mobile and portable receivers

To carry out these research activities, the Group has the following unique facilities:

• audio perception laboratory meeting international standards
• professional quality stereo and multichannel sound recording and reproduction equipment, including a custom hard disk based playback system for listening tests
• general purpose workstations and sophisticated computer simulation software for digital signal processing

The facilities and expertise for conducting audio research and listening tests are unique in North-America. In addition to a calibrated listening room, a unique playback system, based on a computer and a graphic interface, allows totally seamless switching between audio excerpts for critical listening and comparison. The Group has expertise in psychoacoustical experimental design and statistical analysis as well as in signal processing related to digital audio and digital transmission.

Other recent achievements of the Group include:

• the development of computer software for the simulation of the COFDM modulation used in the Eureka 147 DAB system
• the development of CRC-SEAQ, software for the subjective and objective evaluation of audio quality. The objective evaluation is done by means of a computerized model of the human auditory system. This software is commercially available.

The Group has hosted, among other major events, a first series of listening tests in conjunction with the ITU-R to select a low bit-rate digital audio coding standard and a second series of tests for the Electronic Industries Association in the US to evaluate the performance of the proposed digital audio radio (DAR) systems.

The Group wishes to increase its collaborative research and development endeavours with interested partners in the industry.

For more information, contact:

Louis Thibault, Manager
Advanced Audio Systems
Communications Research Centre
3701, Carling Avenue
Ottawa, Ontario, CANADA K2H 8S2
Tel: (613) 990-4349
Fax: (613) 993-9950
E-mail: louis.thibault@crc.gc.ca