我們研究二維度的單穩定型格子動態系統的行進波。首先我們證明存在一個最小的速度使得行進波存在的充分必要條件是行進波的速度大於或等於此最小的速度。然後我們證明給定一個速度後，在不考慮平移的情況下，行進波的波形是唯一的。更進一步的，我們知道行進波的波形是嚴格單調的。

We study traveling waves for a two-dimensional lattice dynamical system with monostable nonlinearity. We first prove that there is a minimal speed such that a traveling wave exists if and only if its speed is above this minimal speed. Then we show the uniqueness (up to translations) of wave profile for each given speed. Moreover, any wave profile is strictly monotone.

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