In this paper, the influences of the injection current and the position offset of SOA on the switching window of TOAD are studied by proceeding simulation and experiment. The increase of the injection current can increase the gain of SOA and the height of switching window. The width of switching window is determined by the position offset of SOA. In the experiment, continuous light was used to replace the signal pulses. With the increase of the position offset of SOA, at first the width of the main switching window increase, then decreases when it equals to half of the control pulse period.