Patent ID: 8494071

Claim:
A reception device which receives a transmission signal in which transmission data of which a level of importance has been previously determined is modulated and transmitted, the reception device comprising: a demodulation unit configured to receive and demodulate the transmission signal, wherein in the transmission signal, (1) a high-importance data string is divided by one bit to generate high-importance bit data each having one bit and added by a fixed-value bit data of one bit to obtain two bit high-importance bit data and (2) a low-importance data string is divided to obtain low-importance bit data each having two bits, and the modulated transmission signal is arranged to symbols based on the respective two bits, and the fixed-value bit data is common to, in the arrangement of the symbols, the symbols of which an Euclidean distance is largest, and the symbol including the high-importance data string is arranged, by adding the fixed-value bit data, to one of two symbols, in the arrangement of the symbols, having the largest Euclidean distance; a symbol decision unit configured to perform symbol decision at each Nyquist interval for the signal demodulated by the demodulation unit; a bit conversion unit configured to convert a symbol value of the symbol obtained on the symbol decision by the symbol decision unit into a bit value; and a data restoration unit configured to compose a data string by deleting the added fixed-value bit data from the data of the bit value converted by the bit conversion unit, and restore the high-importance data string.