Method of transmitting binary data sequences and arrangement for enabling the rapid determination of the end of a transmitted binary data sequence

A communication method and arrangement are disclosed which provide, for a trellis encoding process in the transmitter and a maximum-likelihood decoding process in the receiver, an additional fifth state (ZS) in addition to the usual four coding states (S0 . . . S3). The fifth state is entered in the transmitter at the end of transmission when a particularly selected escape symbol from a set of four escape symbols (E0 . . . E3) each associated to one of the four normal coding states is sent by an encoder supplement (15). In the receiver, a stop signal indicating end of transmission is only generated when, after the usual decoder delay, a path decoder (63) determines that an escape symbol was received, and a trellis decoder (61) indicates the fifth state (ZS) to be the most probable one. This enables rapid and secure determination of the end of a transmitted sequence without the need for additional transmission symbols or decoder cycles.