Interface Technology Design And Implementation Of Speech Quality Objective Assessment System

In the recent decade, modern communication networks are evolving from circuit-switched networks to packet-based networks. Improving the quality of service(QoS) of in-service networks continues to be an important issue. Speech quality is one of the most important dimensions of the QoS. Speech quality assessment can be divided into subjective assessment and objective assessment. Subjective assessment is time-consuming, and can not be effectively repeated. To development a speech objective evaluation system, which is flexible, convenient and reliable, is essential. The work of this thesis includes the following several parts:(1) Relative ITU-T speech objective assessment recommendations are researched, and the PESQ model is researched mainly.(2) A scheme of speech objective evaluation system is presented. In the system, GPS module is utilized to deal with the clock synchronization of signal transmission and receipt. The reference signal and degraded signal are sampled, and be processed in the digital signal processor(DSP). Using USB bus, the results is present on the screen of PC.(3) The development of DSP system is researched. Based on the need of the speech objective evaluation system, appropriate chips are chosen.(4) The characteristic of DSP TMS320VC33 is researched, and USB module and DSP's bootloader module are analyzed.(5) The interface circuit of CH372V-TMS320VC33 is designed. The software of data exchange program between TMS320VC33 and PC is developed, and the application that is realized with MFC based on PC platform is used to control the system by user. So man-machine conversation is implemented.(6) The interface circuit of TMS320VC33-SST39VF800A is designed. The software and hardware of TMS320VC33"s bootloader program are analyzed in detail. The program of writing flash on line is developed based on TMS320VC33 platform with C language, to load and execute programs received from flash.