Broadcasting-quality transmission of audio signals at 64 kbps

Recently, attention has been paid to the problem of transmitting audio signals whose bandwidth is wider than 3.4 kHz, tipycally 7 kHz. In this paper, three techniques are examined which allow the transmission rate of 64 kbit/s to be met. Comparisons are carried out in terms of both objective measurements and informal listening tests. Possible application fields are tele- and video-conferencing, commentary channels and broadcasting, and high quality speech and music in the future Integrated Service Digital Network.