Verfahren und Anordnung zum Übertragen von Sprachsignalen

摘要

In the GSM half-rate encoding method, a complicated code book search method is used which is very intensive in terms of processing. In speech pauses it is known to switch off virtually completely not only the sender but also the speech encoder and still to carry out essentially only the LPC analysis of the speech signal. However, when the speech signal resumes, the filters of the speech encoder must first go through a transient process. For this reason, according to the invention, it is proposed not to switch off the filters even in speech pauses but to drive the filter, which is driven by excitation vectors from the code book, directly with the correspondingly processed speech signal. As a result, upon introducing the speech signal there occurs a more gentle, hardly noticeable transition between the comfort noise and the speech signal. During this switch-off time an artificial background noise, the so-called comfort noise, is generated in the receiver.