Radio device and coefficient update method

A coefficient update method performed by a radio device that includes an amplifier that amplifies electrical power of a signal that is wirelessly sent and a storage that stores therein distortion compensation coefficients each of which compensates distortion generated in the amplifier, the coefficient update method comprising:

• reading, from the storage in a first time section, the distortion compensation coefficients associated with a portion of an input signal input during the first time section and storing the read distortion compensation coefficients in a memory;
• updating, in a second time section, the distortion compensation coefficients stored in the memory and writing the updated distortion compensation coefficients in the storage;
• and
• controlling the reading and the storing such that, when the same input signal is repeatedly input, the distortion compensation coefficients associated with a portion that is different from the portion of the input signal input the last time are stored in the memory in the first time section.