A radio communication apparatus includes a radio signal processing section which produces a first signal. A power calculation section produces a power value signal of the first signal. A correlation detection section produces correlative value signals corresponding to a correlation between the first signal and a known signal. A first and a second detection section detect a beginning of the reception signal, using the power value signal and the correlative value signal respectively. The first and the second detection section respectively produce a first detection and a second detection signal, each of which include information of a beginning timing of the reception signal. A select control section is supplied with the first and the second detection signals and selectively outputs one of them. A demodulation section demodulates a data signal from the first signal using an output signal from the select control section.