A method estimates channels in a wireless cooperative cellular network including a set of base stations, and each base station communicates cooperatively with a set of mobile stations. A first sounding signal including a first midamble is transmitted from a first base station to a first mobile station. A second sounding signal including a second midamble is transmitted simultaneously from a second base station to the first mobile station, wherein the first and second midamble are disjoint in time, and wherein the first and second midambles are used to estimate the channels between the first base station and the first mobile station, and the second base station and the first mobile station, respectively.