SETT OCH ANORDNING FOR OVERFORING AV DIGITAL INFORMATION

摘要

A method for reducing the probability of the loss of a character in a digital transmission employing biphase coding which comprises the steps of identifying the bits out-of-code, that is the bits which don't correspond to the two biphase code configurations; complementing the logic value said bits are given by the demodulator, if there is parity error; inhibiting a character not comprising out-of-code bits, but in which parity error occurs or if two or more out-of-code bits are present in the character. The circuit implementing the method comprises shift register means for storing the information bits and control signals identifying the out-of-code bits; parity check means; complementing means for complementing the logic state which are given by the demodulator to the out-of-code bits, said complementing means being conditioned by the simultaneous occurrence of the out-of-code bit and the parity error in a character; logic means for inhibiting the character in presence of parity error alone or of two or more out-of-code bits.