A wireless base station apparatus and wireless terminal apparatus with a configuration which can prevent reductions in the accuracy of channel estimation when non-contiguous band transmission and SRS transmission are employed in an uplink line. In the base station apparatus (100), an allocation setting unit (106), which sets the reception band of an SRS at an SRS extraction unit (103) and sets the units of frequency allocation (RBG) at a CQI estimation unit (104) and allocation unit (105), matches the frequency position at the end of the SRS reception band to the frequency position at the end of any of the units of frequency allocation and sets the reception bandwidth of the reference signal to a natural number multiple of the bandwidth of the unit of frequency allocation. In the terminal apparatus (200), a band information setting unit (204), which sets the transmission band and units of frequency allocation (RBG), matches the frequency position at the end of the transmission band to the frequency position at the end of any of the units of frequency allocation and sets the transmission bandwidth of the SRS to a natural number multiple of the bandwidth of the unit of frequency allocation.