A multicarrier communication apparatus capable of reducing an amount of information required for feedback, making a range of transmission power fluctuation small, and achieving rapid convergence on a target transmission power is disclosed. A radius of curvature of a corner portion formed at a point of intersection between the incidence side surface and each of side surfaces adjacent to the incidence side surface is not larger than 0. The spools are independently rotatable relative to the shell. Respective key input screens are located at any of the hierarchy.