Patent ID: 7873103

Claim:
A digital broadcast transmitter comprising: a randomizer to randomize a transport stream to produce randomized data, the transport stream including at least one robust data packet; a known data inserting unit to insert specified known data known by a receiver of the transmitter; a first Reed-Solomon (RS) encoder to perform an RS-encoding of data output from the known data inserting unit; an interleaver to interleave the first RS encoded robust data packet; a trellis encoder to perform a trellis encoding of data output from the interleaver; a second RS encoder to change a parity of parity data used by the trellis encoder by performing an RS encoding of the robust data of the trellis-encoded data and to input the changed parity data to the trellis encoder to replace existing parity data previously used by the trellis encoder; and a modulator to modulate data from the trellis encoder and to perform a Radio Frequency (RF) up-converting of the modulated data.