PURPOSE: To transmit additional information without decreasing transmission efficiency by positively utilizing the performance of an error correction code.

CONSTITUTION: An analog signal (a) such as an audio signal is converted into a PCM data signal (b), and (n) PCM data signals are made into one unit block; and a synchronizing signal SYNC and a correction code are added to said block of a PCM signal data sequence (c) to obtain a signal sequence (e). Then, a PCM data signal (k) in this signal sequence (e) is replaced in a specific period by additional information ADD such as absolute address information to obtain a signal sequence (g), which is transmitted (or recorded). During regeneration, the additional information ADD is extracted from a received signal sequence (h) to obtain a signal sequence (i), and the replaced PCM data signal (k) in the string is restored by using the correction code to regenerate an original signal sequence (j), and each PCM data signal (k) is D/A-converted to obtain an analog signal l.