US Patent 7812618 Printed circuit board, and backplane data transmission method

In a receiving-side printed circuit board, a reflected-waveform analyzing unit analyzes a reflected wave generated in a transmission line on a backplane along with transmission of a signal from a transmitting-side printed circuit board, and acquires waveform data that indicates a waveform of the reflected wave. An input signal identifying unit calculates a size of the reflected wave that is currently received based on the waveform data and data on previously received signals. The input signal identifying unit corrects a threshold value by the calculated size, and identifies a state of a bit indicated by the signal from the transmitting-side printed circuit board.