A convolutional interleaver included in a time interleaver, which performs convolutional interleaving includes: a first switch that switches a first connection destination of an input terminal of the convolutional interleaver to one end of one of a plurality of branches; a plurality of FIFO memories provided in some of the plurality of branches except one branch, wherein a number of FIFO memories is different among the plurality of branches; and a second switch that switches a second connection destination of an output terminal of the convolutional interleaver to the other end of one of the plurality of branches. The first and second switches switch the first and second connection destinations, respectively, when the plurality of cells as many as the codewords per frame have passed, by switching a corresponding branch of the first and second connection destinations sequentially and repeatedly among the plurality of branches.