The present invention provides a wireless terminal apparatus, including a reception unit for receiving a multi-carrier signal generated by applying an N-point (where N is a natural number) inverse fast Fourier transform (IFFT) to a plurality of sub-carriers to which transmission information for a plurality of wireless terminal apparatuses is allocated; a fast Fourier transform unit for extracting a plurality of the sub-carriers from the multi-carrier signal; a thin-out unit, being placed at the front stage of the fast Fourier transform unit, capable of changing, from the N points, a sampling number of the multi-carrier signals which are digitalized; and a judgment unit for discerning, based on sub-carrier allocation information accompanying the multi-carrier signal, whether or not the sub-carrier of another wireless terminal apparatus overlaps with that of the wireless terminal apparatus itself in the case of changing the sampling number from the N points, and determining a sampling number for the thin-out unit.