L^1 Estimate for the Dissipative Wave Equation in a Two Dimensional Exterior Domain

We consider the initial-boundary value problem in a two dimensional exterior domain for the dissipative wave equation (∂2ｔ+∂- △)u= 0 with the homogeneous Dirichlet boundary condition. Using the so-called cut-off technique together with the local energy estimateand L1 and L2 estimates in the whole space，we derive the LP estimates with 1≤p≤∞ for the solution.