Patent ID: 7974799

Claim:
A backboard transmission method comprising: monitoring a signal wave passed between a transmission-side substrate unit and a reception-side substrate unit to detect a delay time and a gain of a reflected wave with respect to the signal wave, the transmission-side substrate unit and the reception-side substrate unit being mounted with integrated circuits and connected to a backboard via respective connectors, the reflected wave being a wave generated when a transmitted wave from the transmission-side substrate unit to the reception-side substrate unit is reflected on sheet connectors of the reception-side substrate unit and the transmission-side substrate unit, the signal wave being the transmitted wave superimposed by the reflected wave; performing delay adjustment with respect to a cancellation wave having a characteristic identical with that of the signal wave based on the delay time detected at the monitoring; performing gain adjustment with respect to the cancellation wave based on the gain detected at the monitoring; and superimposing the cancellation wave subjected to the delay adjustment and the gain adjustment on the signal wave thereby canceling the reflected wave.