Data transmission apparatus data reception apparatus, data transmission method, data reception method, and transfer system

A data transmission method comprising the steps of:

• apportioning data of n channels to portions of each of blocks each capable of accommodating data of m channels where n≦m;
• generating a transmitted-data stream matching a predetermined transmission format;
• providing said transmitted-data stream with determination information included therein for determining whether or not any of said portions pertaining to each of said blocks is allocated to a channel not assigned to valid data;
• and
• transmitting said transmitted-data stream.

A data reception method comprising the steps of:

• receiving a transmitted-data stream transmitted in a predetermined transmission format including blocks of digital data;
• determining whether or not any of said portions pertaining to each of said blocks composing said received transmitted-data stream is allocated to a channel not assigned to valid data on the basis of determination information included in said received transmitted-data stream;
• and
• obtaining data of channels each assigned to valid data from said received transmitted-data stream.

A transmission system comprising a data transmission apparatus for transmitting digital data in a predetermined transmission format by division of said data into blocks and a data reception apparatus for receiving said transmitted digital data wherein:

• said data transmission apparatus comprises:
• transmitted-data generation means for apportioning data of n channels to portions of each of said blocks each capable of accommodating data of m channels where n≦m, generating a transmitted-data stream matching said transmission format, and providing said transmitted-data stream with determination information included therein for determining whether or not any of said portions pertaining to each of said blocks is allocated to a channel not assigned to valid data;
• and
• transmission means for transmitting said transmitted-data stream generated by said transmitted-data generation means, whereas
• said data reception apparatus comprises:
• reception means for receiving a transmitted-data stream, which includes blocks of digital data and is transmitted in a predetermined transmission format;
• and
• received-data-processing means for determining whether or not any of portions pertaining to each of said blocks composing said transmitted-data stream received by said reception means is allocated to a channel not assigned to valid data on the basis of determination information included in said transmitted-data stream and obtaining data of channels each assigned to valid data from said transmitted-data stream.