A tensioning device for tensioning a radome fabric (7, 8), which device comprises a substantially circular, upper tensioning profile (3, 5) and a substantially circular, lower tensioning profile (4, 6), which is disposed in parallel with and axially displaced relative to the upper tensioning profile, between which tensioning profiles the radome fabric is tensioned in order to form a radome (1), wherein at least one of the tensioning profiles (3, 4, 5, 6) comprises a fabric contact portion (9), which exhibits a convex contact surface (10) for interacting with an edge portion of the radome fabric.