Cellular terminal with echo suppressor

摘要

For access to a GSM type mobile communications network and provision of basic telecommunications services to a telephone terminal (TT) connected to it. It is derived from a GSM mobile cellular terminal with a line interface that consists of a two-wire conversion circuit (H) connected to the transmit path (TP) and the receive path (RP), and to the subscriber line to which the telephone terminal (TT) is connected, and thereby perform a four-to-two wire conversion. It also comprises an echo suppressor (ES) that precedes the two-wire conversion circuit (H), consisting of two signal attenuators (ATT1,ATT2) inserted in the transmit and receive paths and activated by means of an attenuation control module (ATTC) that receives the two signals coming from the voice activity detector and from the silence descriptor frame detector present in GSM type cellular terminals. <IMAGE>