Adaptive Primary Speech Signals Codecs for Software-Configured Radio Systems
Sergey Nikolaevich Kirillov, Vladimir Timurovich Dmitriev · 2020
Algorithms for software-configured adapting primary codecs to acoustic noise are considered, as well as adaptation under the influence of interference in communication channel in order to ensure the optimal ratio of restored speech quality at minimum transmission speed based on the theorem of V.A. Kotelnikov and Khurgin-Yakovlev representation. The analysis of primary codecs providing the best quality of restored speech at encoder output under the action of various types of acoustic noise is carried out. It is shown that the use of Khurgin-Yakovlev representation provides additional gain in the quality of reconstructed speech signal by 0.1 ... 0.5 points, according to GOST R 50840-95 with separate coding of signal samples and the first derivative, simpler implementation of synthesizing filters, as well as the possibility of parallel processing. An algorithm for adapting Khurgin-Yakovlev in the structure of adaptive codec is proposed. The application of this algorithm allows increasing the quality of restored speech by 1 ... 1.5 points according to GOST R 50840-95 under the action of acoustic noise in comparison to similar non-adaptive codecs based on the theorem of V.A. Kotelnikov or the possibility of reducing transmission speed by 15 ... 30% for software-configured radio systems to receive, transmit and process information.