DATA SEQUENCE GENERATOR, TRANSMITTER, INFORMATION DATA DECODER, RECEIVER, TRANSMITTER-RECEIVER, DATA SEQUENCE GENERATING METHOD, INFORMATION DATA DECODING METHOD, AND RECORDING MEDIUM

摘要

The invention is the object to reduce the probability of discarding a variable length frame by establish both synchronization of a variable length frame and protection of header information in the variable length frame, and suppress the increase of redundancy of transmission data in an environment where an code error is liable to occur. The transmitter side stores a specified unique word (specific information), error-detection-encoded data of header information n necessary for decoding the nth information data and establishing a frame synchronization, error-detection- encoded data of frame length information indicating the frame length of a frame n, and error-detection-encoded data of header information n-1 of a frame n-1 of one frame before in the frame n storing the nth information data. The receiver side receives the frame header of the frame n, and determines the timing of a frame synchronization by using frame length information when the frame length information has been transmitted without an error and by detecting the unique word and header information of the next frame from a received signal sequence (data sequence) in the other cases, and detects header information n-1 inserted in a position (directly after the frame length information) in the frame n corresponding to the timing and decodes information data in a frame of one frame before by means of the header information n-1 when the frame header in the frame of one frame before has not been decoded successfully.