Patent ID: 7889766

Claim:
A digital broadcast transmitter comprising: a pre-processor configured to perform pre-processing on mobile service data, wherein the pre-processor comprises: a block processor configured to encode the mobile service data at a coding rate of 1/N, wherein N is an integer greater than 1, a group formatting unit configured to map the mobile service data encoded at the coding rate of 1/N by the block processor into a data group, and add main service data place holders and non-systematic RS (Reed-Solomon) parity data place holders to the data group, a deinterleaver configured to deinterleave the data group, and a packet formatter configured to remove the main service data place holders and the non-systematic RS parity data place holders in the deinterleaved data group, and output mobile service data packets having the mobile service data; a packet multiplexer configured to multiplex the mobile service data packets with main service data packets having main service data; and a post processor configured to perform post-processing on the multiplexed data packets, the post-processor comprising: a systematic/non-systematic RS encoder configured to perform systematic RS encoding on the main service data packets of the multiplexed data packets, and perform non-systematic RS encoding on the mobile service data packets of the multiplexed data packets, and a data interleaver configured to perform convolutional byte interleaving on the systematic RS-encoded main service data packets and the non-systematic RS-encoded mobile service data packets.