With respect to a wireless communication system comprising a transmitter device 200, which is equipped with a function for performing inflated lattice precoding (ILP) on transmission data, and a receiver device 300, which receives a signal transmitted from the transmitter device and restores data, there is adopted a feature wherein “coefficient α” which is required when the transmitter device 200 performs the above-mentioned ILP, and which is also required when the receiver device performs data restoration, is uniquely derived using information relating to an MCS (modulation parameter) that is applied with respect to the wireless communication system (more specifically, a feature wherein a “coefficient table part,” which uniquely maps MCS information to coefficient α, is provided at both the transmitter device and the receiver device, and wherein coefficient α required at both the transmitter device and the receiver device is derived using this “coefficient table part”), thereby evading having to exchange information relating to “coefficient α” between the transmitter device and the receiver device.