Patent ID: 8010878

Claim:
A data transmission method of making transmission by including variable length transmission data into each frame that has a fixed time length, said data transmission method comprising: at a transmitting side, a step of calculating an error detecting code of the transmission data in each frame; a step of placing the calculated error detecting code after the transmission data in each frame, and generating frame data by rearranging an R-bit series before a final bit position of the error detecting code in inverse order in each frame; and a step of transmitting the generated frame data, and at a receiving side, a step of receiving the frame data; a step of assuming the transmission data and the error detecting code for the received frame data by assuming a final bit position of the frame data in each frame; a step of making a determination in each frame that, among the assumed final bit positions of the frame data, a position that is determined to be errorless as a result of error detection carried out on a basis of the assumed transmission data and error detecting code is the final bit position of the frame data; and a step of obtaining the transmission data on a basis of the determination result in each frame, wherein the step of assuming the transmission data and error detecting code assumes the transmission data and error detecting code in each frame on a presumption that the error detecting code is placed after the transmission data, and the R-bit series before the final bit position of the error detecting code is rearranged in inverse order; and said R is a natural number equal to or greater than 2, and is greater or smaller than the number of bits of the error detecting code.