Variable bit rate digital circuit multiplication equipment with tandem passthrough function

摘要

Digital circuit multiplication equipment (DCME) refers to coding bit rate information included in a pseudo-speech signal. In accordance with the coding bit rate information, the DCME selects either a coded speech signal extracted by a transmission bit rate restorer (19) or a coded speech signal including bit rate identification information added by a coding bit rate information adding section (30), and supplies the selected coded speech signal to a bearer line. The DCME can solve a problem of a conventional DCME in that a mismatch can take place between the actual transmission bit rate of the coded speech signal and the transmission bit rate assigned to the bearer line when providing the variable bit rate DCME with a tandem passthrough function, and therefore the correct coding bit rate information cannot be transferred to a speech decoder, bringing about serious degradation in the speech quality. <IMAGE>