Abstract: During data processing of ocean ambient noise near a ship channel , it was found that the originally almost constant noise coherence stripes exhibited asymmetric bending when ship passes by the hydrophone pair,. Within a continuous measurement period of 35 hours, the bending pattern of the coherence stripes changed twice. In order to explain this experimental phenomenon, the coherogram when the ship passes by is simulated based on the noise model near the shallow water channel in this paper. However, the simulated noise vertical coherence according to the preset parameters of the hydrophone pair could not explain the experimental phenomenon. By observing the depth data measured by the temperature-depth recorder when the measured coherence abruptly changed, it was speculated that the hydrophone pair tilted during that time. Under the assumption of the tilted array, with real-time ship positions provided by the automatic identification system (AIS), coherogram simulation of the measured noise of three ships at different time period were achieved, explaining the three types of bending phenomena in the measured coherogram and the abrupt changes in noise coherence. The research approach in this paper can provide technical support for explaining abnormal noise phenomena, estimating changes in array and waveguide parameters based on noise coherence.