Patent ID: 8144258

Claim:
A method of processing broadcast data in a broadcast transmitter, the method comprising: performing, by a Reed Solomon (RS) encoder, RS encoding and Cyclic Redundancy Check (CRC) encoding on mobile service data, thereby packaging the mobile service data into an RS frame; mapping, by a group formatter, a portion of the RS frame into at least one region of a group that comprises a plurality of regions, and adding a first known data sequence, a plurality of second known data sequences, a transmission parameter, and MPEG header data holder bytes to the group; replacing, by a packet formatter, the MPEG header data holder bytes in the group with MPEG header data, thereby outputting mobile service data packets; multiplexing, by a multiplexer, the mobile service data packets with main service data packets including main service data; trellis encoding, by a trellis encoder, data in the multiplexed data packets; and modulating, by a modulator, a broadcast signal including the trellis-encoded data, wherein the first known data sequence has a first pattern and the plurality of second known data sequences have a second pattern that is different from the first pattern, wherein the transmission parameter is positioned between the first known data sequence and one of the plurality of second known data sequences, and wherein the first known data sequence and the one of the plurality of second known data sequences differ from each other in length.