Patent ID: 7822134

Claim:
A digital broadcast transmitter, comprising: a pre-processor configured to pre-process mobile service data, the mobile service data being included in a first data group, wherein the pre-processor is further configured to de-interleave the first data group to output a second data group, the first data group having first and second segments, the first segments having first known data, the second segments having second known data, the number of data bytes for the first known data being different from the number of data bytes for the second known data, M second segments being positioned between an Nth first segment and an (N+k)th first segment, L second segments being positioned between the (N+k)th first segment and (N+k+i)th first segment, wherein M, L, N, k and i are natural numbers, M≠L, and each packet in the second data group has a length of 207 bytes; and a multiplexer configured to multiplex mobile service data packets having the mobile service data with main service data packets having main service data.