Patent ID: 7953185

Claim:
A receiving unit of a vehicle communication system utilizing a coding scheme, wherein the coding scheme generates a binary level change between a high level and a low level at least one of in a middle of each bit of digital data and at an end of each bit of digital data, wherein the digital data is transmitted by having a carrier wave modulated by the coding scheme that encodes the digital data into digital signal, wherein the transmitted digital signal transmitted from a transmitter is received for de-modulation, and wherein a binary level of one of the high level and the low level of a de-modulated analog demodulation signal is determined for restoring the digital data based on a determination result of the demodulation signal, the receiving unit comprising: a first signal output unit that outputs a high level decision signal in an active level when the analog demodulation signal is higher in level after comparing the analog demodulation signal and a high level threshold; a second signal output unit that that outputs a low level decision signal in the active level when the analog demodulation signal is lower in level after comparing the analog demodulation signal and a low level threshold; a synchronization signal activation unit generating a synchronization signal based on the high level decision signal and the low level decision signal, whereby a determination period of the binary level of the analog demodulation signal is determined as a period between the edge interval of the synchronization signal; a level decision unit that determines the binary level of the demodulation signal either as a high level, as a low level or as an indefinite level in each of the determination periods based on the high level decision signal and the low level decision signal wherein the binary level is determined as an indefinite level if the binary level of the analog demodulation signal in the determination period is determined as neither of the high level or the low level, and a level correction unit that corrects the indefinite level to be in either one of the high level and the low level based on a determination result of the level decision unit and a rule of the coding scheme.