A signal processing system which discriminates between voice signals and data signals modulated by a voiceband carrier. The signal processing system includes a voice exchange, a data exchange and a call discriminator. The voice exchange is capable of exchanging voice signals between a switched circuit...http://www.google.de/patents/US7092365?utm_source=gb-gplus-sharePatent US7092365 - Voice and data exchange over a packet based network with AGC
