Localized coherent structures of the (2+1) dimensional Broer-Kaup equations
(2+1)维Broer-Kaup 方程的局域相干结构

The linearization form of (2+1) dimensional Broer Kaup equations is established by using the improved homogeneous balance method. Starting from this lineaization form of the equation, a variable separation solution with the entrance of some arbitrary functions is obtained, and the very rich localized coherent structures are revealed. Some special types of the dromion solutions, breathers, instantons and ring soliton solutions are discussed by appropriately selecting arbitrary functions. The dromion solutions can be driven by some sets of straight line and curved line ghost solitons. These solutions may be located not only at the cross points of the lines, but also at closed points of the curves,. The breather may breath both in amplitude and in shape.