BANDWIDTH EXTENSION OF NARROWBAND SPEECH

摘要

A system for extending the bandwidth of a narrow-band speech signal is provided to extend a signal bandwidth at a receiving end and improve speech recognition quality in a noisy environment. A bandwidth extending system(100) extends the bandwidth of the narrow-band speech signal to a broadband spectrum. The system includes a high-band generator(102) which generates a high-frequency spectrum based on a narrow-band spectrum, and a background noise generator(104) which generates a high-frequency background noise spectrum based on background noise in the narrow-band spectrum. Summation circuits(134,136) linked to the high-band generator and the background noise generator combine the high-frequency spectrum and the narrow-band spectrum with the high-frequency background noise spectrum.