Abstract: Vertical linear array can span the whole wave-guide and can sample most normal modes accurately in the shallow water wave-guide.This paper introduces a method that is using MOATL normal mode to simulate a signal in the place of vertical linear array as its take-over signal.Then reverse this signal and make it pass through the reverse wave channel modeled by KRAKEN normal mode.Obvious retrofocusing effects can be seen in the place of sound source.Then the paper analyses how retrofocusing effect changes when the sensor number,the distance between sensors,and the width of source wave frequency alter.Finally it concludes that augmenting the sensor number,the distance between sensors,and the width of source wave frequency properly can improve the time-reversal retrofocusing effect.