a subscriber line interface circuit in a packet switched network is capable of reducing the s / n ratio . voice signals are transmitted and received as analog signals via line terminal circuits which are corrected to respective packet communication signal processing circuits but not to a common bus . in the packet communication signal processing circuits , packet assembly and disassembly , voice signal processing , and line terminal circuit control are carried out in synchronism with the packet communication network . packet data are transferred serially between the packet communication signal processing circuits and a switch interface circuit .