Patent ID: 8522284

Claim:
A receiving system comprising: a signal receiving unit configured to receive a broadcast signal including a parade of data groups and main service data, wherein at least one of the data groups includes a plurality of data blocks, signaling information and known data sequences and wherein the signaling information is inserted into a fourth data block of the plurality of data blocks, wherein a first known data sequence of the known data sequences is located in a third data block of the plurality of data blocks, second and third known data sequences of the known data sequences are located in a fourth data block of the plurality of data blocks, and fourth, fifth and sixth known data sequences of the known data sequences are located, respectively, in fifth, sixth and seventh data blocks of the plurality of data blocks, wherein the first, third, fourth, fifth and sixth known data sequences are spaced apart by specific segments and have the same pattern; a demodulating unit configured to demodulate the broadcast signal; a detector configured to detect at least one of the known data sequences; an equalizer configured to perform channel equalization upon the demodulated broadcast signal using the detected at least one known data sequence; a signaling information decoder configured to decode the signaling information, wherein the signaling information includes a Reed Solomon (RS) frame mode indicating the number of RS frames built per the parade; and a decoder configured to decode mobile service data to build the RS frames including the mobile service data depending on the RS frame mode, wherein the decoder builds one RS frame when the RS frame mode indicates a single frame mode, and wherein the decoder builds two RS frames when the RS frame mode indicates a dual frame mode, wherein at least one of the RS frames includes a plurality of packets, wherein each of the plurality of packets includes a header and a payload, wherein the payload includes a plurality of Internet Protocol (IP) datagrams, and wherein the header includes point field information indicating a starting point of a first new IP datagram in the payload.