Wideband Speech Enhancement Addition

Abstract : This report describes the completion of the development and construction of a speech enhancement unit (SEU). This is an electronic instrument that automatically detects and attenuates tones, clicks, and wideband random noises that may accompany speech signals that are transmitted, recorded, or reproduced electronically. An earlier version of this device was tested extensively by the Air Force and then was returned to Queens College for modification and completion of the system. During the period that is covered by this report, a number of major changes were made in the SEU, leading to a device that is simpler to use, more effective, and more broadly useful in its intended area or application. Some of the changes that were made in the SEU were aimed at reducing the degree of operator intervention that was required. To this end, the SEU was greatly simplified and made more automatic. The manual Digital Spectrum Shaping (DSS) system and most of the manual controls were removed. A new system was added for adjusting the level of the input signal. It keeps the signal at the level that maximizes the effectiveness of the noise attenuation processes. The INTEL process for attenuating wideband random noise was incorporated into the SEU. To make it possible for the speech enhancement unit to operate in real- time with all processes active, the hardware and software of the system were modified extensively. The MAP was upgraded by adding a second arithmetic processor and a high speed memory. The existing programs and algorithms were rewritten to reduce their execution times. These and the INTEL programs were modified to fully exploit the capabilities of the upgraded MAP. (Author)