A data reception device is provided with: a puncture rate detection
element to detect the puncture rate of received data, an interpolation
element to interpolate bits decimated at the detected puncture rate, a
deinterleaving element to restore interleaved data to the original
arrangement, and a turbo-decoding element, while variably setting the
length of the learning interval according to the puncture rate detected
by the puncture rate detection element, to input sliding window data and
the data of the above learning interval following the data of the sliding
window to the data processed by the interpolation element and
deinterleaving element, and to perform recursive operations to decode the
data of the sliding window. The valid received signal contained in the
learning interval can be maintained approximately constant even if the
puncture rate changes.